Manual 210M

This material is proprietary to Komatsu Mining Systems, Inc. and is notto be reproduced, used, or disclosed except in accordance with writtenauthorization from Komatsu Mining Systems, Inc.

It is the policy of the Company to improve products whenever it is possibleand practical to do so. The Company reserves the right to make changesor add improvements at any time without incurring any obligation to installsuch changes on products sold previously.

Because of continuous research and development, periodic revisionsmay be made to this publication. Customers should contact their localdistributor for information on the latest revision.

CALIFORNIAProposition 65 Warning

Diesel engine exhaust and some of its constituents are known tothe State of California to cause cancer, birth defects and otherreproductive harm.

Unsafe use of this machine may cause serious injury or death.Operators and maintenance personnel must read and understandthis manual before operating or maintaining this machine. This manual should be kept in or near the machine for reference,and periodically reviewed by all personnel who will come intocontact with it.

FOREWORD

This Service Manual is written for use by the service technician and is designed to help the technicianbecome fully knowledgeable of the truck and all its systems in order to keep it running and inproduction. All maintenance personnel should read and understand the materials in this manualbefore performing maintenance and/or operational checks on the truck. All safety notices, warningsand cautions should be understood and followed when accomplishing repairs on the truck.

The first section covers component descriptions, truck specifications and safe work practices, as wellas other general information. The major portion of the manual pertains to disassembly, service andreassembly. Each major serviceable area is dealt with individually. For example: The disassembly,service and reassembly of the radiator group is discussed as a unit. The same is true of the engineand engine accessories, and so on through the entire mechanical detail of the truck. Disassemblyshould be carried only as far as necessary to accomplish needed repairs.

The illustrations used in this manual are, at times, typical of the component shown and may notnecessarily depict a specific model.

This manual shows dimensioning of U.S. standard and metric (SI) units throughout and all referencesto "Right", "Left", "Front", or "Rear" are made with respect to the operator’s normal seated position,unless specifically stated otherwise.

Standard torque requirements are shown in torque charts in the general information section andindividual torques are provided in the text in bold face type, such as 100 ft.lbs. (135 N.m) torque. Alltorque specifications have ± 10% tolerance unless otherwise specified.

A Product Identification plate is normally located on the truck frame in front of the right side frontwheel and designates the Truck Model Number, Product Identification Number (vehicle serialnumber), and Maximum G.V.W. (Gross Vehicle Weight) rating.

The HAULPAK® Model designation consists of three numbers and one letter (i.e. 210M). The threenumbers represent the basic truck model. The letter "M" designates a Mechanical drive and the letter"E" designates an Electrical propulsion system.

The Product Identification Number (vehicle serial number) contains information which will identify theoriginal manufacturing bill of material for this unit. This complete number will be necessary for properordering of many service parts and/or warranty consideration.

The Gross Vehicle Weight (GVW) is what determines the load on the drive train, frame, tires, and othercomponents. The vehicle design and application guidelines are sensitive to the total maximum GrossVehicle Weight (GVW) and this means the total weight: the Empty Vehicle Weight + the fuel &lubricants + the payload.

To determine allowable payload: Service all lubricants for proper level and fill fuel tank of empty truck (which includes all accessories,body liners, tailgates, etc.) and then weigh truck.Record this value and subtract from the GVW rating. The result is the allowable payload.NOTE: Accumulations of mud, frozen material, etc. become a part of the GVW and reduces allowablepayload. To maximize payload and to keep from exceeding the GVW rating, these accumulationsshould be removed as often as practical.

Exceeding the allowable payload will reduce expected life of truck components.

A00010 8/95 Introduction A-1

"DANGER" IDENTIFIES A SPECIFIC POTENTIAL HAZARD WHICH WILL RESULT

IN EITHER INJURY OR DEATH IF PROPER PRECAUTIONS ARE NOT TAKEN.

"WARNING" IDENTIFIES A SPECIFIC POTENTIAL HAZARD WHICH MAY RESULT

IN EITHER INJURY OR DEATH IF PROPER PRECAUTIONS ARE NOT TAKEN.

"CAUTION" IS USED FOR GENERAL REMINDERS OF PROPER SAFETY PRACTICES

OR TO DIRECT THE READER’S ATTENTION TO AVOID UNSAFE

OR IMPROPER PRACTICES WHICH MAY RESULT IN DAMAGE TO THE EQUIPMENT.

THIS "ALERT" SYMBOL IS USED WITH THE SIGNAL WORDS,"CAUTION", "DANGER", AND "WARNING" IN THIS MANUAL TOALERT THE READER TO HAZARDS ARISING FROM IMPROPEROPERATING AND MAINTENANCE PRACTICES.

A-2 Introduction A00010 8/95

TABLE OF CONTENTS

SUBJECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SECTION

GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A

STRUCTURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B

ENGINE, FUEL, COOLING AND AIR CLEANER . . . . . . . . . . . . . . . . . . . . . . . . . . C

ELECTRIC SYSTEM (24 VDC. NON-PROPULSION) . . . . . . . . . . . . . . . . . . . . . . . . D

TRANSMISSION AND PTO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F

DRIVE AXLE, SPINDLES AND WHEELS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G

HYDRAIR® II SUSPENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H

BRAKE CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J

HYDRAULIC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L

OPTIONS AND SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M

OPERATOR’S CAB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N

LUBRICATION AND SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P

ALPHABETICAL INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Q

SYSTEM SCHEMATICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . R

A00010 8/95 Introduction A-3

210M HAULPAK® TRUCK

A-4 Introduction A00010 8/95

SECTION A

GENERAL INFORMATION

INDEX

TRUCK COMPONENT DESCRIPTION & SPECIFICATIONS . . . . . . . . . . . . . . . . . . . A2-1

GENERAL SAFETY AND TRUCK OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . A3-1

WARNINGS AND CAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A4-1

CHARTS AND TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A5-1

STORAGE PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7-1

A01001 2/94 Index A1-1

NOTES

A1-2 Index A01001 2/94

COMPONENT DESCRIPTION AND SPECIFICATIONS

ENGINEThe 210M HAULPAK® is powered by a CumminsKTTA--19C diesel engine. The truck is capable ofspeeds up to 35 MPH (56.7 km/h).

TRANSMISSIONThe diesel engine drives a remote-mounted AllisonCLT-6062 transmission incorporating a TC683 torqueconverter. The transmission has six speeds "Forward"and one "Reverse" and uses Allison Transmission Elec-tronic Control (ATEC) for complete automatic shiftsequencing. By moving the operator’s Range Selectorin the cab, the operator may select "R" for Reverse, "N"for Neutral or any one of six Forward driving ranges.

The Range Selector is an electronic-mechanical con-trol unit. Each position (R,N,D,5,4,3,2,1) is selected byreleasing a range locking mechanism on the lever andchoosing the desired range. "D" will permit completelyautomatic up and down shifts through all six ranges."5" will limit upshifts to 5th range only. "4" will limitupshifts to 4th range only. "3" will limit upshifts to 3rdrange only. "2" will limit upshifts to 2nd range only. "1"is a first range hold position and no upshifts are permit-ted.

DYNAMIC RETARDINGDynamic retarding is actuated by depressing the op-erator’s retarder pedal which applies oil-cooled, rearmounted, wet disc brakes only; the front brakes are notapplied. Application of the retarder pedal may be fully modu-lated and should be used to slow the truck duringnormal truck operation, to control speed coming downa grade or to make non-emergency stops. Use of theretarder pedal saves wear on the front brakes andprovides better steering control.

SERVICE BRAKE SYSTEMThe service brakes are controlled by an all hydraulicactuation system. Depressing the service brake pedalactuates front dry disc brakes and rear wet disc brakes.

Automatic Emergency Braking is provided if systempressure falls below a preset value. All functioningwheel brakes will be automatically applied by accumu-lators.

POWER STEERINGThe HAULPAK® Truck is equipped with an orbitalpower steering system mounted under the cab floorwith noise and vibration isolators. Emergency powerto safely steer the truck while stopping is providedautomatically by an accumulator.

INSTRUMENTSThe instrument panel located in the cab provides theoperator easy identification of all instruments andgauges which are necessary to control the truck andmonitor the truck’s operating systems.

SUSPENSIONHYDRAIR® II suspension cylinders located at eachwheel provide a smooth and comfortable ride for theoperator and dampens shock loads to the chassisduring loading.

FINAL DRIVEPlanetary Final Drive has full floating axle shafts and aplug-in differential carrier assembly.

A02015 01/92 Component Description and Specifications A2-1

MODEL 210M HAULPAK® MAJOR COMPONENTS

A2-2 Component Description and Specifications A02015

The SPECIFICATIONS listed on these pages cover standard production. When optional equipment is selected, someof these specifications and/or capacities may change.

ENGINECummins . . . . . . . . . . . . . . . . . KTTA--19CNumber of Cylinders . . . . . . . . . . . . . . . . 6Operating Cycle . . . . . . . . . . . . . . 4-StrokeRated Brake HP (SAE) 675 HP (504kW) @ 2100 RPMFlywheel HP (SAE) . 641 HP (478kW) @ 2100 RPMMaximum Torque:

. . . . . . . 1990 ft. lbs. (2698 N.m) @ 1400 RPM

TRANSMISSION ALLISON CLT-6062 w/ATECTorque Converter . . . . . . . . . . . . . . . TC6836 Speeds FORWARD . . . . . . . . . . 1 REVERSE

SUSPENSION HYDRAIR® IIStroke (Front & Rear) . . . . . . 10.88 in. (276 mm)

FINAL DRIVERatios:

Bevel Set (differential) . . . . . . . . . . . 3.85:1Planetary . . . . . . . . . . . . . . . . . . 5.70:1

Total Reduction . . . . . . . . . . . . . . . . 21.93:1Maximum Speed . . . . . . . . 35 MPH (56.7 km/h)

TIRES (Standard) 24.00-35, 36 PR(E-3)Rating Ton-MPH (m/ton-km/h) . . . . . . 180 (262.8)

24 VDC ELECTRIC SYSTEMBatteries . . . . . . . Two 12 Volt Batteries in Series

Capacity . . . . . . . . . . . . . 200 Ampere-HourAlternator . . . . . . . . 24 Volt, 75 Amperes OutputStarter . . . . . . . . . . . . . . . . . DELCO-REMYLighting . . . . . . . . . . . . . . . . . . 24 Volt-DC

SERVICE CAPACITIES U.S. Gallons LitersEngine Lube Oil:

Cummins . . . . . . . . . . . . . . 13 49.2Cooling System . . . . . . . . . . . . 48 181.7Fuel Tank . . . . . . . . . . . . . . 154 583.7Hydraulic System (incl. tank) . . . . 144 545.0

Hydraulic Tank . . . . . . . . . . . 95 359.6Transmission . . . . . . . . . . . . . 20 75.6Final Drive . . . . . . . . . . . . . . . 56 212.2Front Spindle . . . . . . . . . . . . . 1 3.8

HOIST SYSTEMTandem Pump Capacity:

Shaft End . . . . 94 gpm (355 l/min.) @ 2100 RPMCover End . . . . 80 gpm (303 l/min.) @ 2100 RPM

Relief Valve Pressure Setting 2750 psi (18961 kPa)Hoist Cylinders . . . . 2 - Stage Hydraulic CylindersFiltration . . . . . Full-Flow, Remote-Mounted Filter

Return . . . . . . Full Flow, 12 Micron - Absolute

SERVICE BRAKESActuation . . . . . . . . . . . . . . . . All HydraulicType:

(Front) Single Dry Disc with 2 Caliper Assy./WheelTotal Braking Surface . . . 408 in.2 (2 632 cm2)

(Rear) . . . . . . Dual Wet Disc Brake AssembliesTotal Braking Surface . . 9020 in.2 (58 193 cm2)

STEERINGTurning Circle . . . . . . . . . . . . 69 ft. (21.0 m)Pump Capacity . . . . . . . . . 22.7 gpm (85.9 lpm)System Pressure . . . . . . . . 2750 psi (19.0 MPa)

DUMP BODY CAPACITIES

PAYLOAD (Rated) 55 Ton (49.9 mt)Capacitiy:

Struck . . . . . . . . . . 31.1 cu. yds. (23.8 m3)Heaped @ 2:1 (SAE) . . 44.0 cu. yds. (33.7 m3)

BODYMaterial [Yield Strength] . . . . . . . . . Thickness

Floor [125,000 psi (862 mPa)Steel] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.75 in. (19 mm)Front [90,000 psi (620 mPa)Steel] 0.50 in. (13 mm)Sides [90,000 psi (620 mPa)Steel] 0.38 in. (10 mm)

WEIGHT DISTRIBUTIONEMPTY - STANDARD . . . . Pounds Kilograms

Front Axle . . . . . . . . . . . 44,390 20 135Rear Axle . . . . . . . . . . . 45,910 20 824Total . . . . . . . . . . . . . . 90,300 40 959

LOADED . . . . . . . . . . Pounds KilogramsFront Axle . . . . . . . . . . . 66,700 30 255Rear Axle . . . . . . . . . . 133,600 60 600Total . . . . . . . . . . . . . 200,300 90 855

MAXIMUM ALLOWABLE GVW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210,000 95 340

A02015 01/92 Component Description and Specifications A2-3

OVERALL TRUCK DIMENSIONS

A2-4 Component Description and Specifications A02015

GENERAL SAFETY

This safety section also contains precautions for optional equipment and attachments.

SAFETY RULES

• ONLY trained and authorized personnel can operate and maintain the machine.

• Follow all safety rules, precautions and instructions when operating or performing maintenance on the machine.

• When working with another operator or a person on worksite traffic duty, be sure all personnel understand allhand signals that are to be used.

SAFETY FEATURES

• Be sure all guards and covers are in their proper position. Have guards and covers repaired if damaged. (See Walk-Around Inspection, Operating Instructions later in this section.)

• Learn the proper use of safety features such as safety locks, safety pins, and seat belts, and use these safetyfeatures properly.

• NEVER remove any safety features. ALWAYS keep them in good operating condition.

• Improper use of safety features could result in serious bodily injury or death.

CLOTHING AND PERSONAL PROTECTIVE ITEMS

• Avoid loose clothing, jewelry, and loose long hair. They can catch on controls or in moving parts and causeserious injury or death. Also, do not wear oily clothes because they areflammable.

• Wear a hard hat, safety glasses, safety shoes, mask or gloves whenoperating or maintaining the machine. Always wear safety goggles, hardhat and heavy gloves if your job involves scattering metal chips or minutematerials----this is so particularly when driving pins with a hammer andwhen cleaning the air cleaner element with compressed air. Check alsothat there is no one near the machine.

UNAUTHORIZED MODIFICATION

• Any modification made without authorization from Komatsu can create hazards.

• Before making a modification, consult your Komatsu distributor. Komatsu will not be responsible for any injuryor damage caused by any unauthorized modification.

Read and follow all safety precautions. Failure to do so mayresult in serious injury or death.

A03002 4/98 General Safety & Operation A3-1

STANDING UP FROM THE SEAT

• To prevent any accident occurring if you should touch any control lever that is not locked, always carry out thefollowing before standing up from the operator’s seat.

• Place the shift control lever at neutral (N) and set the parking lever to the PARKING position.

• Lower the dump body, set the dump lever to the HOLD position, then apply the lock.

• Stop the engine. When leaving the machine, always lock everything. Always remember to take the key with you.If the machine should suddenly move or move in an unexpected way, this may result in serious bodily injury ordeath.

MOUNTING AND DISMOUNTING

• NEVER jump on or off the machine. NEVER get on or off a moving machine.

• When getting on or off the machine, face the machine and use the handhold and steps.

• Never hold any control levers when getting on or off the machine.

• Always maintain three-point contact with the handholds and steps to ensure that you support yourself.

• When bringing tools to the operator’s compartment, always pass them by hand or pull them up by rope.

• If there is any oil, grease, or mud on the handholds or steps, wipe it off immediately. Always keep these partsclean. Repair any damage and tighten any loose bolts.

• Use the handrails and steps marked by arrows in the diagram below when getting on or off the machine.A: For use when getting on or off the machine from the left door.B: For use when getting on or off the machine from the engine hood or right door.

FIRE PREVENTION FOR FUEL AND OIL

Fuel, oil, and antifreeze can be ignited by a flame. Fuel is particularly FLAMMABLE and can be HAZARDOUS.

• Keep flame away from flammable fluids.

• Stop the engine and do not smoke when refueling.

• Tighten all fuel and oil tank caps securely.

• Refueling and oiling should be made in well ventilated areas.

• Keep oil and fuel in the determined place and do not allow unauthorized persons to enter.

A3-2 General Safety & Operation A03002 4/98

PRECAUTIONS WHEN HANDLING AT HIGH TEMPERATURES

• Immediately after operations, the engine cooling water, engine oil, and hydraulic oil are at high temperature andare under pressure. If the cap is removed or the oil or water is drained or the filters are replaced, there is dangerof serious burns. Always wait for the temperature to go down, and carry out the operation according to the specifiedprocedure.

• To prevent hot water from spurting out:1) Stop the engine.2) Wait for the water temperature to go down.

3) Turn the cap slowly to release the pressure before removing the cap.

• To prevent hot oil from spurting out:1) Stop the engine.2) Wait for the oil temperature to go down.

3) Turn the cap slowly to release the pressure before removing the cap.

ASBESTOS DUST HAZARD PREVENTION

Asbestos dust can be HAZARDOUS to your health if it is inhaled.If you handle materials containing asbestos fibers, follow these guidelines as givenbelow:

• NEVER use compressed air for cleaning.

• Use water for cleaning to keep down the dust.

• Operate the machine with the wind to your back, whenever possible.

• Use an approved respirator if necessary.

PREVENTION OF INJURY BY WORK EQUIPMENT

• Never enter or put your hand or arm or any other part of your body between movable parts such as the dumpbody and chassis or cylinders. If the work equipment is operated, the clearance will change and this may leadto serious bodily injury or death.

FIRE EXTINGUISHER AND FIRST AID KIT

• Be sure fire extinguishers have been provided and know how to use them.

• Provide a first aid kit at the storage point.

• Know what to do in the event of a fire.

• Be sure you know the phone numbers of persons you should contact in case ofan emergency.


PRECAUTIONS WHEN USING ROPS

• If ROPS is installed, the ROPS must never be removed when operating the machine.

• The ROPS is installed to protect the operator if the machine should roll over. If is designed not only to supportthe load if the machine should roll over, but also to absorb the impact energy.

• The Komatsu ROPS fulfills all of the regulations and standards for all countries, but if it is rebuilt withoutauthorization or is damaged when the machine rolls over, the strength will drop and it will not be able to fulfill itsfunction properly. It can only display its performance if it is repaired or modified in the specified way.

• When modifying or repairing the ROPS, always contact your Komatsu distributor.

• Even if the ROPS is installed, it cannot show its full effect if the operator does not fasten the seat belt properly.Always fasten the seat belt when operating.

PRECAUTIONS FOR ATTACHMENTS

• When installing and using an optional attachment, read the instruction manual for the attachment and theinformation related to attachments in this manual.

• Do not use attachments that are not authorized by Komatsu or your Komatsu distributor. Use of unauthorizedattachments could create a safety problem and adversely affect the proper operation and useful life of themachine.

• Any injuries, accidents, and product failures resulting from the use of unauthorized attachments will not be theresponsibility of Komatsu.


PRECAUTIONS DURING OPERATION

BEFORE STARTING ENGINE

SAFETY AT WORKSITE

• Before starting the engine, thoroughly check the area for any unusual conditions that could be dangerous.

• Examine the road surface in the jobsite and determine the best and safest method of operation.

• Choose an area where the ground is as horizontal and firm as possible before carrying out the operation.

• If you need to operate on a road, protect pedestrians and cars by designating a person for worksite traffic dutyor by installing fences around the worksite.

• Check the river bed condition, and depth and flow of water before crossing shallow parts of river. NEVER be inwater which is in excess of the permissible water depth.

• The operator must check personally the work position, roads to be used, and existence of obstacles before startingoperations.

• Always determine the travel roads in the worksite and maintain them so that it is always safe for the machinesto travel.

FIRE PREVENTION

• Thoroughly remove wood chips, leaves, paper and other flammable things accumulated in the engine compart-ment. They could cause a fire.

• Check fuel, lubrication, and hydraulic systems for leaks. Have any leaksrepaired. Wipe up any excess oil, fuel or other flammable fluids.

• Be sure a fire extinguisher is present and working.

• Do not operate the machine near any flame.

IN OPERATOR’S CAB

• Do not leave tools or spare parts lying around in the operator’s compartment. They may damage or break thecontrol levers or switches. Always put them in the tool box on the right side of the machine.

• Keep the cab floor, controls, steps and handrails free of oil, grease, snow, and excess dirt.

• Check the seat belt, buckle and hardware for damage or wear. Replace any worn or damaged parts. Always useseat belts when operating your machine.

VENTILATION FOR ENCLOSED AREAS

• If it is necessary to start the engine within an enclosed area, provide adequate ventilation.Exhaust fumes from the engine can KILL.


KEEP MIRRORS, WINDOWS, AND LIGHTS CLEAN

• Remove any dirt from the surface of the windows or lights to ensure good visibility.

• Adjust the rear view mirror to a position where the operator can see best from the operator’s seat, and keep thesurface of the mirror clean. If any glass should break, replace it with a new part.

• Check that the machine is equipped with the head lamps and working lamps needed for the operating conditions.Check that all the lamps light up properly.


OPERATING MACHINE

WHEN STARTING ENGINE

• Walk around your machine again just before mounting it, checking for people and objects that might be in theway.

• NEVER start the engine if a warning tag has been attached to the control.

• When starting the engine, sound the horn as an alert.

• Start and operate the machine only while seated.

• Do not allow any person other than the operator in the operator’s compartment or any other place on the machine.

• For machines equipped with a back-up alarm buzzer, check that the alarm buzzer works properly.

CHECK WHEN TRAVELING IN REVERSE

Before operating the machine or work equipment, do as follows:

• Sound the horn to warn people in the area.

• Check that there is no one near the machine. Be particularly careful to checkbehind the machine.

• If necessary, designate a person to check the safety. This is particularlynecessary when traveling in reverse.

• When operating in areas that may be hazardous or have poor visibility,designate a person to direct worksite traffic.

• Do not allow any one to enter the line of travel of the machine. This rule mustbe strictly observed even on machines equipped with a back-up alarm or rear view mirror.

TRAVELING

• When traveling on rough ground, travel at low speed. When changing direction, avoid turning suddenly.

• Lower the dump body and set the dump lever to the FLOAT position when traveling.

• If the engine should stop when the machine is traveling, the steering wheel will not work, and it will be dangerousto drive the machine. Apply the brakes immediately and stop the machine.

TRAVELING ON SLOPES

• Traveling on slopes could result in the machine tipping over or slipping.

• Do not change direction on slopes. To ensure safety, go down to level ground before turning.

• Do not travel up and down on grass, fallen leaves, or wet steel plates. These materials may make the machineslip on even the slightest slope. Take all possible steps to avoid traveling sideways, and always keep the travelspeed low.

• When traveling downhill, use the retarder brake to reduce speed. Do not turn the steering wheel suddenly. Donot use the foot brake except in an emergency.

• If the engine should stop on a slope, apply the brakes fully and apply the parking brake, also, to stop the machine.


ENSURE GOOD VISIBILITY

• When working in dark places, install working lamps and head lamps, and set up lighting in the work area ifnecessary.

• Stop operations if the visibility is poor, such as in mist, snow, or rain, and wait for the weather to improve to acondition that allows the operation to be carried out safely.

OPERATE CAREFULLY ON SNOW

• When working on snowy or icy roads, there is danger that the machine may slip to the side on even the slightestslope, so always travel slowly and avoid sudden starting, turning, or stopping.

• Be extremely careful when carrying out snow-clearing operations. The road shoulder and other objects are buriedin the snow and cannot be seen.

• When traveling on snow-covered roads, always install tire chains.

AVOID DAMAGE TO DUMP BODY

• When working in tunnels, on bridges, under electric cables, or when entering a parking place or any other placewhere there are height limits, always drive extremely carefully and lower the dump body completely before drivingthe machine.

DO NOT GO CLOSE TO HIGH-VOLTAGE CABLES

• Going close to high-voltage cables can cause electric shock. Always maintain the safe distance given belowbetween the machine and the electric cable.

• The following actions are effective in preventing accidents:1) Wear shoes with rubber or leather soles.2) Use a signalman to give warning if the machine approaches too close to the electric cable.

• If the work equipment should touch the electric cable, the operator should not leave the operator’s compartment.

• When carrying out operations near high voltage cables, do not let anyone come close to the machine.

• Check with the electricity company about the voltage of the cables before starting operations.

Voltage Min. Safety Distance

6.6 kV 3 m 10 ft

33.0 kV 4 m 14 ft

66.0 kV 5 m 17 ft

154.0 kV 8 m 27 ft

275.0 kV 10 m 33 ft


WHEN DUMPING

• Before starting the dumping operation, check that there is no person or object behind the machine.

• Stop the machine in the correct position, and check again that there is no person or object behind the machine.Give the determined signal, then slowly operate the dump body. If necessary, use blocks for the wheels or positiona flagman.

• When carrying out dumping operations on slopes, the machine stability will become poor and there is dangerthat it may tip over. Always carry out such operations extremely carefully.

• Do not travel with the dump body raised.

WORKING ON LOOSE GROUND

• Avoid operating your machine too close to the edge of cliffs, overhangs, and deep ditches. If these areas collapse,your machine could fall or tip over and result in serious injury or death. Remember that the soil after heavy rainor blasting is weakened in these areas.

• Earth laid on the ground and the soil near ditches are loose. They can collapse under the weight or vibration ofyour machine.

• When operating in places where there is danger of falling rocks or danger of the machine turning over, alwaysinstall ROPS and a seat belt.

WHEN LOADING

• Check that the surrounding area is safe, stop the machine in the correct loading position, then load the bodyuniformly.

• Do not leave the operator’s seat during the loading operation.

PARKING THE MACHINE

• Choose a horizontal road surface to park the machine. If the machine has to be parked on a slope, always putblocks under all the wheels to prevent the machine from moving.

• When parking on public roads, provide fences and signs, such as flags or lights, on the machine to warnpedestrians and other vehicles. Be sure that the machine, flags, or lights do not obstruct the traffic.

• Before leaving the machine, lower the dump body fully, set the parking lever to the PARKING position, stop theengine, then lock everything. Always take the key with you.


BATTERY

BATTERY HAZARD PREVENTION

• Battery electrolyte contains sulfuric acid and can quickly burn the skin and eat holes in clothing. If you spill acidon yourself, immediately flush the area with water.

• Battery acid could cause blindness if splashed into the eyes. If acid gets into the eyes, flush them immediatelywith large quantities of water and see a doctor at once.

• If you accidentally drink acid, drink a large quantity of water or milk, beaten egg or vegetable oil. Call a doctor orpoison prevention center immediately.

• When working with batteries ALWAYS wear safety glasses or goggles.

• Batteries generate hydrogen gas. Hydrogen gas is very EXPLOSIVE, and is easily ignited with a small spark offlame.

• Before working with batteries, stop the engine and turn the starting switch to the OFF position.

• Avoid short-circuiting the battery terminals through accidental contact with metallic objects, such as tools, acrossthe terminals.

• When removing or installing, check which is the positive (+) terminal and negative (-) terminal.

• Tighten the battery cap securely.

• Tighten the battery terminals securely. Loosened terminals can generate sparks and lead to an explosion.

STARTING WITH BOOSTER CABLES

• ALWAYS wear safety glasses or goggles when starting the machine with booster cables.

• When starting from another machine, do not allow the two machines to touch.

• Be sure to connect the positive (+) cable first when installing the booster cables. Disconnect the ground or negative(-) cable first when removing them.

• If any tool touches between the positive (+) terminal and the chassis, it will cause sparks. This is dangerous, sobe sure to work carefully.

• Connect the batteries in parallel: positive to positive and negative to negative.

• When connecting the ground cable to the frame of the machine to be started, be sure to connect it as far aspossible from the battery.


TOWING

WHEN TOWING, FIX WIRE TO HOOK

• Towing in the wrong way may lead to serious personal injury or damage.

• When using another machine to tow this machine, use a wire rope with ample strength for the weight of thismachine.

• Never tow a machine on a slope.

• Do not use any towing rope that has kinks or is twisted.

• Do not stand astride the towing cable or wire rope.

• When connecting a machine that is to be towed, do not let any one come between the towing machine and themachine that is being towed.

• Set the coupling of the machine being towed in a straight line with the towing portion of the machine, and secureit in position.

(For towing method, see "Operating Instructions" later in this section or in Section 3 in the Operation &Maintenance Manual.)


PRECAUTIONS FOR MAINTENANCE

BEFORE CARRYING OUT MAINTENANCE

WARNING TAG

• If others start the engine or operate the controls while you are performing service or lubrication, you could sufferserious injury or death.

• ALWAYS attach the WARNING TAG to the control lever in the operator’s cab to alert others that you are workingon the machine. Attach additional warning tags around the machine, if necessary.

• These tags are available from your Komatsu distributor. (Part No. 09963-03000)

PROPER TOOLS

• Use only tools suited to the task. Using damaged, low quality, faulty, or makeshift toolscould cause personal injury.

PERIODIC REPLACEMENT OF CRITICAL PARTS

• Periodically replace parts used to insure safety or prevent accident. (See ‘‘PERIODIC REPLACEMENT OFCOMPONENT PARTS FOR SAFETY DEVICES’’, Section 4.)

• Replace these components periodically with new ones, regardless of whether or not they appear to be defective.These components deteriorate over time.

• Replace or repair any such components if any defect is found, even though they have not reached the timespecified.

STOPPING THE ENGINE BEFORE SERVICE

• When carrying out inspection or maintenance, always stop the machine on firm flat ground, lower the dump body,then stop the engine.

• If the engine must be run during service, such as when cleaning the radiator, always set the shift control lever tothe neutral position (N) and the parking brake lever to the PARKING position. Always carry out the work with twopeople. One person should sit on the operator’s seat so that he can stop the engine if necessary. NEVER moveany controls you do not need to operate.

• When servicing the machine, be careful not to touch any moving part or get your clothes caught.

• Put blocks under the wheels.

• When carrying out service with the dump body raised, always place the dump lever at the HOLD position, applythe lock, and insert the safety pins securely.


DURING MAINTENANCE

PERSONNEL

• Only authorized personnel can service and repair the machine. Extra precaution should be used when grinding,welding, and using a sledge-hammer.

ATTACHMENTS

• Place attachments that have been removed from the machine in a safe place so that theydo not fall. If they fall on you or others, serious injury could result.

WORK UNDER THE MACHINE

• Always lower all movable work equipment to the ground or to their lowest position beforeperforming service or repairs under the machine.

• Always block the tires of the machine securely.

• Never work under the machine if the machine is poorly supported.

KEEP THE MACHINE CLEAN

• Spilled oil or grease, or scattered tools or broken pieces are dangerous becausethey may cause you to slip or trip. Always keep your machine clean and tidy.

• If water gets into the electrical system, there is danger that the machine may notmove or may move unexpectedly.Do not use water or steam to clean the sensors, connectors, or the inside of theoperator’s compartment.

RULES TO FOLLOW WHEN ADDING FUEL OR OIL

• Spilled fuel and oil may cause you to slip, so always wipe it up immediately.

• Always tighten the cap of the fuel and oil fillers securely.

• Never use fuel for washing any parts.

• Always add fuel and oil in a well-ventilated place.


RADIATOR WATER LEVEL

• If it is necessary to add water to the radiator, stop the engine and allow the engineand radiator to cool down before adding the water.

• Slowly loosen the cap to relieve pressure before removing the cap.

USE OF LIGHTING

When checking fuel, oil, coolant, or battery electrolyte, always use lighting withanti-explosion specifications. If such lighting equipment is not used, there isdanger or explosion.

PRECAUTIONS WITH BATTERY

• When repairing the electrical system or when carrying out electrical welding,remove the negative (-) terminal of the battery to stop the flow of current.

HANDLING HIGH-PRESSURE HOSES

• Do not bend high-pressure hoses or hit them with hard objects. Do not use any bent or cracked piping, tubes orhoses. They may burst during use.

• Always repair any loose or broken fuel hoses or oil hoses. If fuel or oil leaks, it may cause a fire.

PRECAUTIONS WITH HIGH PRESSURE OIL

• Do not forget that the work equipment circuits are always under pressure.

• Do not add oil, drain oil, or carry out maintenance or inspection before completely releasing the internal pressure.

• If oil is leaking under high pressure from small holes, it is dangerous if the jet of high-pressure oil hits your skinor enters your eyes. Always wear safety glasses and thick gloves, and use a piece of cardboard or a sheet ofwood to check for oil leakage.

• If you are hit by a jet of high-pressure oil, consult a doctor immediately for medical attention.


PRECAUTIONS WHEN CARRYING OUT MAINTENANCE AT HIGH TEMPERATURE OR HIGH PRESSURE

• Immediately after stopping operations, the engine cooling water and oil at all partsare at high temperature and under high pressure.In this condition, if the cap is removed, or the oil or water are drained, or the filtersare replaced, it may result in burns or other injury. Wait for the temperature to godown, then carry out the inspection and maintenance in accordance with theprocedures given in this manual.

ROTATING FAN AND BELT

• Keep away from rotating parts and be careful not to let anything get caught in them.

• If your body or tools touch the fan blades or fan belt, they may be cut off or sent flying,so never touch any rotating parts.

WASTE MATERIALS

• Never dump waste oil in a sewer system, rivers, etc.

• Always put oil drained from your machine in containers. Never drain oil directlyon the ground.

• Obey appropriate laws and regulations when disposing of harmful objects suchas oil, fuel, coolant, solvent, filters, batteries, and others.


TIRES

HANDLING TIRES

If tires are not used under the specified conditions, they may overheat and burst or be cut and burst by sharp stoneson rough road surfaces. This may lead to serious injury or damage.

To maintain safety, always keep to the following conditions:

• Inflate the tires to the specified pressure. Abnormal heat is generated particularly when the inflation pressure istoo low.

• Use the specified tires.

The values given in this manual for the tire inflation pressure and permissible speed are general values. The actualvalues may differ depending on the type of tire and the condition under which they are used. For details, pleasecontact your Komatsu distributor or tire maker.

If the tires become hot, a flammable gas is produced, and this may ignite. It is particularly dangerous if the tiresbecome overheated when the tires are under pressure. If the gas generated inside the tire ignites, the internal pressurewill suddenly rise, and the tire will explode, and this may lead to serious personal injury. Explosions differ frompunctures or tire bursts, because the destructive force is extremely large. Therefore, thefollowing operations are strictly prohibited when the tire is under high internal pressure:

• Welding the rim

• Building fires or carrying out welding near the wheel or tire.

If you do not understand the proper procedure for carrying out maintenance or replacement of the wheel or tire, andyou use the wrong method, the wheel or tire may burst and cause serious injury or damage. When carrying out suchmaintenance, please consult your Komatsu distributor or tire maker.

STORING TIRES AFTER REMOVAL

• As a basic rule, store the tires in a warehouse which unauthorized persons cannot enter. If the tires are storedoutside, always erect a fence around the tires and put up ‘‘No Entry’’ and other warning signs that even youngchildren can understand.

• Stand the tire on level ground, and block it securely so that it cannot roll or fall over.

• If the tire should fall over, get out of the way quickly. The tires for construction equipment are extremely heavy,so trying to hold the tire may lead to serious injury.


SAFETY RULES

Safety records of most organizations will show that thegreatest percentage of accidents are caused by un-safe acts of persons while the remainder are causedby unsafe mechanical or physical conditions.

The following safety rules are intended to instruct thetruck operator on what to do and not to do whileoperating the truck. However, all situations cannot becovered by these safety rules; local conditions andregulations may add many more to this list.

GENERAL

1. Prevention is the best safety program. Preventaccidents by knowing all the safety regulationsrequired by the employer, all necessary precau-tions at the job site, and the manufacturer’s rec-ommendations for the truck. Report anyconditions that need attention to the properauthorities.

2. Wear proper clothing. Loose fitting clothing, un-buttoned jackets and sleeves, jewelery, etc. cancatch on a protrusion and cause a potential haz-zard.

3. Always use personal safety equipment such assafety shoes, safety glasses and hard hat. Theremay be conditions when ear protective devicesshould also be worn.

4. When walking to or from the truck, keep a safedistance from all machines even if the operator isvisible.

Before Starting Engine

1. Carefully study the Operator Handbook beforestarting engine or driving truck. Give particularattention to safety material and caution and warn-ing decals. Only qualified operators or techni-cians should attempt to operate the truck.

2. Before operating truck, a careful visual inspectionas well as operational checks should be com-pleted. Report any items that need attention to theproper authority.

a. Inspect entire truck for oil or coolant leaks.

If engine has been running, allow coolant to coolbefore removing the fill cap or draining radiator.

Any operating fluid, such as hydraulic oil, or en-gine coolant escaping under pressure, can havesufficient force to enter a person’s body by pene-trating the skin and cause serious injury and pos-sibly death, if proper medical treatment by aphysician who is familiar with this type of injury isnot received immediately.

b. When checking coolant in radiator, relievepressure before removing radiator cap.

c. Check tires for cuts, damage or "bubbles".Check tires for proper inflation. If tire is warmfrom operation, allow tire to cool before adjust-ing tire pressure. If inflation is needed, use anair chuck with extension hose clipped on thetire inflation valve to allow service away fromfront of wheel.

d. Visually inspect all headlights, worklights, clear-ance lights, and taillights for damage and becertain lenses are clean. Good visibility mayprevent an accident.

e. Upon completion of an exterior inspection ofthe truck, clean mud, grease, ice or snow fromshoes and ladder before climbing access lad-der.

f. Always use handrails and ladder when mount-ing or dismounting truck.

Always mount and dismount facing the truck.Never attempt to mount or dismount while thetruck is in motion.

g. Check the deck areas for debris or loose hard-ware.

h. When getting in or out of truck cab, face thecab and use handrails provided.

A03002 4/98 Safety Rules A3-17

i. Become familiar with all protective equipmentdevices on the truck and insure that theseitems (seat belts, grab bars, anti-skid material,canopies, etc.) are securely in place.

j. Check on-board fire extinguishers. Do not usea fire extinguisher for any purpose other thanextinguishing a fire. If extinguisher is used,report the occurrence so it may be refilled orreplaced.

Starting Engine And General Operation

1. Make sure all persons are clear of truck beforestarting engine. Always sound the horn as awarning device before activating any controls.When backing the truck, give backup signal (threeblasts on horn); when starting forward, two blastson horn. These signals must be given each timethe truck is moved forward or backward.

2. Insure adequate ventilation before startup if thetruck is in an enclosure. Exhaust fumes are dan-gerous.

3. If a cold weather starting aid is used, read andfollow the manufacturer’s instructions for use anddisposal.

Starting fluid is highly flammable. Use with ex-treme care.

4. Check windshield wipers, lights, windows andhorn for proper operation and cleanliness.

5. Operate each of the truck brake circuits at leasttwice prior to operating and moving the truck.These checks should include individual activa-tions of the service brake, parking brake, andbrake lock with the engine running. If any appli-cation/release of any brake circuit does not ap-pear proper, or if sluggishness is apparent onapplication/release, shut the truck down and no-tify maintenance personnel. DO NOT operatetruck until brake circuit in question is fully opera-tional.

Use brake lock at dump or loading site ONLY. DONOT use brake lock to park the truck with engineshut down or to stop the truck during routineoperation.

6. Check parking brake periodically during shift. Useparking brake for parking only.

7. Observe safety and warning decals on the truckat all times.

8. Keep all unauthorized reading material out of truckcab.

9. Do not carry tools and supplies in cab of truck orallow trash to accumulate in cab.

10. Do not allow anyone to ride on decks or steps oftruck. Riders should be in cab only.

11. Only authorized persons are allowed to ride in thetruck cab. Wear seat belts at all times.

12. Do not allow anyone to get on or off truck while itis in motion.

13. Do not move truck into or out of a building withouta signal person present.

14. DO NOT leave truck unattended while engine isrunning.

15. Check for flat tires periodically during shift. If truckhas been run on a "flat", it must not be parked ina building until the tire cools.

If tire must be changed, do not stand in front ofrim and locking ring when inflating tire mountedon the machine. Initial inflation to required pres-sure must be done with a safety cage or rackenclosing the tire and rim assembly. Observersshould not be permitted in the area and should bekept at least 1500 ft. (457 m) away from the sideof such tires.

Do not weld or apply heat on the rim assembly withthe tire mounted on the rim. Resulting gases insidethe tire may ignite causing explosion of tire andrim.

In the event of fire in the tire and wheel area(including brake fires), stay away from the truckuntil the tire and wheel are cool. Tire and rimassembly may explode if subjected to excessiveheat. Personnel should move to a remote or pro-tected location if sensing excessively hot brakes,smell of rubber burning or evidence of fire near tireand wheel area.

A3-18 Safety Rules A03002 4/98

If the truck must be approached to extinguish afire, those personnel should do so only from thefront or the back of the tire, unless protected byuse of large heavy equipment as a shield. Stay atleast 50 feet (15 m) from the tread of the tire.

16. Report haul road, pit or dump conditions whichmay present hazzards (muddy roads, ice, snow,pot holes, spilled debris, etc.) immediately to su-pervisor.

Loading

1. Pull into the loading area with caution. Remain ata safe distance while truck ahead of you is beingloaded.

2. Do not drive over unprotected power cables.

3. When approaching or leaving a loading area,watch out for other trucks and for personnel work-ing in the area.

4. When positioning truck under shovel, follow"Spotter" or "Shovel Operator" signals. Operatormay speed up loading operations by watchingtruck position ahead of him in order to judgewhere he is to place his unit.

5. While truck is being loaded, operator should stayin cab of truck. Apply brake lock during loadingoperation.

6. After truck is loaded, pull away from shovel withcaution.

Hauling

1. Stay alert! Govern truck speed by the road condi-tions, weather and visibility.

2. Always operate truck so it is under control at alltimes.

3. Use extreme caution when approaching a haulroad intersection. Be prepared to avoid collisionswith other vehicles. Watch for oncoming vehiclesand be prepared to slow down and move aside ifhaul road is restricted.

4. Obey all road signs.

5. If unfamiliar with the road, drive with extra caution.

6. Always dim headlights when meeting oncomingvehicles.

7. Maintain a safe distance when following anothertruck. Never approach another truck from therear, in the same lane, closer than 50 ft. (15 m).When operating on a down grade, this distanceshould be no closer than 100 ft. (30 m).

8. Before starting up or down a grade, maintain aspeed that will insure safe driving and provideeffective retarding under all conditions. Refer tospeed/grade decal in operator cab.

9. When operating truck in darkness or when visibil-ity is poor, do not move truck unless headlightsare on. Do not back truck without a spotter ifbackup horn or lights are inoperative.

10. When backing the truck, give backup signal (threeblasts on horn); when starting forward, two blastson horn. These signals must be given each timethe truck is moved forward or backward.

11. Do not stop or park on a haul road unless unavoid-able. If you must stop, move truck to a safe place,apply parking brake, block wheels securely andnotify maintenance personnel for assistance.

12. Cab doors should remain closed at all times whiletruck is in motion or unattended.


Passing

1. Use only the areas designated for passing. Beforepassing, make sure the road ahead is clear.

2. Do not pass another vehicle on a hill or blind curve.

3. If a disabled truck is blocking your lane, slow downand pass with extreme caution.

Dumping

1. Pull into dump area using caution. Carefully ma-neuver truck into dump position. Obey signals asdirected by the spotter, if present.

2. When in dump position, apply wheel brake lockand move selector switch to "Neutral" position.

3. Put hoist control lever in "Hoist" position anddepress throttle pedal.

4. Remove foot from throttle pedal as last stage ofhoist cylinder starts to extend.

5. After load has been dumped, place hoist controllever in the down position and release the leverallowing the body to return to the frame.

6. With body completely down against frame, leavethe dump area.

The truck is not to be moved with the dump bodyraised EXCEPT IN EMERGENCIES.

Failure to follow this CAUTION may result in hoistcylinder, frame, and/or body hinge pin damage.

Parking

1. When parking, park only in designated parkingareas and at a safe distance from other vehiclesas determined by supervisor.

2. If parking truck in other than designated parkingarea is necessary, select a level area, applyparking brake and block wheels front and rear. Donot use brake lock as a parking brake.

3. If necessary to park on a slope, park at right anglesto the incline and block wheels securely.

4. When parking do not leave truck unattended ifengine is left running or if dump body is raised.

5. If engine is to be shut down, follow procedureoutlined under "Shutting Down Engine".

Shutting Down Engine

1. Bring truck to complete stop, move range selectorto the "Neutral" position and apply parking brake.

2. Allow engine to run from 3 to 5 minutes at idle toprovide cooling of the engine.

Do not leave truck unattended during engine idlecool down period.

3. Turn off all lights and accessories.

4. Engine shutdown may be activated when key-switch is moved to the "Off" position on sometrucks; other trucks may require depressing andholding a shutdown button until the engine stops.Refer to the Operator Handbook for specificmodel information. Some trucks may include anoptional "Ground Level Shutdown" button .

5. Close and lock all windows, remove key fromkey-switch and lock cab to prevent unauthorizedtruck operation. Dismount truck properly.


When Service Is Necessary

1. If truck is to be towed for any reason, use a rigidtow bar. Check truck cab for decal recommendingspecial towing precautions. Refer to "Towing"instructions for further precautions.

2. When truck body is in the dump position, do notallow anyone beneath it unless "body-up" retain-ing cable or pins are installed.

3. Do not repair or service truck while engine isrunning, except when adjustments can only bemade under such conditions. Keep a safe dis-tance from moving parts.

4. When servicing air conditioning system with re-frigerant, wear a face shield and cold resistantgloves for protection against freezing.

5. Follow package directions carefully when usingcleaning solvents.

6. If an auxiliary battery assist is needed, turn off allaccessories and be sure area is well ventilated.

NOTE: HAULPAK Trucks are generally equipped withtwo 12 volt batteries connected in series to provide 24volt output. Be sure to maintain correct voltage andpolarity when connecting booster cables. Damage toelectrical components may result if voltage and polarityare not correct.

Lead-sulphate batteries will give off hydrogen gas!Sparks or flame near these batteries may cause aviolent explosion which will expel debris and ex-tremely toxic and corrosive sulphuric acid!

Use the following procedure to minimize the pos-sibility of sparks in the vicinity of the battery:

a. Connect one lead of booster cable to 24Vpositive (+) post of battery needing assist, andother lead of the booster cable to the 24Vpositive (+) post of auxiliary battery.

b. Connect one lead of second booster cable to24V negative (-) post of auxiliary battery andthen connect other lead of the booster cable toa good frame ground on the disabled truckaway from the battery needing assist.

Towing

Prior to towing a truck, many factors must be carefullyconsidered. Serious personal injury and/or significantproperty damage may result if important safety prac-tices, procedures and preparation for moving heavyequipment are not observed.

Both right and left planetary sun gears/drive axlesshould be removed before any towing. Refer toSection "G" for these instructions. Extensive sec-ondary damage can occur to final drive compo-nents and/or transmission, if truck is towedwithout first removing sun gears/drive axles.

A disabled truck may be towed after the followingMINIMUM precautions have been taken.

1. Shut down engine.

2. Refer to operator’s cab for towing decal for anyspecial instructions.

3. If truck is equipped, install hydraulic connectionsfor steering and dumping between towing andtowed vehicles.

4. Inspect tow bar for adequacy (approximately 1.5times the gross vehicle weight of truck beingtowed).

5. Determine that towing vehicle has adequate ca-pacity to both move and stop the towed truckunder all conditions.

6. Protect both operators in the event of tow barfailure.

7. Block disabled truck to prevent movement whileattaching tow bar.

8. Release disabled truck brakes and remove block-ing.

Do not tow the truck any faster than 5 MPH (8 kph).

9. Sudden movement may cause tow bar failure.Smooth and gradual truck movement is preferred.

10. Minimize tow angle at all times - NEVER EXCEED30o. The towed truck must be steered in the direc-tion of the tow bar.


NOTES


WARNINGS AND CAUTIONS

The following paragraphs give an explanation of theWarning, Caution, Danger and Service Instructionplates and decals attached to the truck. The plates anddecals listed here are typical of this model HAULPAK®,but because of customer options, individual trucksmay have plates and decals that are different fromthose shown here.

The plates and decals must be kept clean and legible.If any decal or plate becomes worn or unable to beread, it should be replaced with a new one. Orderreplacements by the part number shown at the bottomof the plate or decal.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Engine idle decal WA9706 is located in the cab, abovethe windshield. The operator is cautioned that damagecan occur to the turbocharger if the engine is notproperly idled for three minutes before shutdown.These instructions are very important.

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

The WA9721 towing "Caution" decal is located to theright of operator, above the windshield. Do not tow thetruck without first removing the sun gears and sunshafts from the planetary drive. If these parts are notremoved, damage to the transmission and/or final drivewill result when the truck is towed. Refer to Section "G",Planetary Drive, for instructions.

Do not tow the truck faster than 5 MPH (8 KPH).

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

WA9741Caution decal is located inside the cab abovethe windshield. It cautions the operator that the maxi-mum brake oil temperature is 250oF (121oC) and maxi-mum engine speed is 2350 RPM. Exceeding theselimits may result in vehicle damage. The graph pro-vides speed guide lines to be used to maintain theselimits when descending various grades with a loadedtruck.

When descending a grade and applying the retarderpedal, the operator should observe both the Tachome-ter and the Brake Oil Temperature Gauge. The engineRPM must be maintained at 1650 -- 2350 RPM (greenarea on tachometer) and the Brake Oil Temperaturemust be maintained below 250oF (121oC).

If the operator observes that either of these values areabout to be exceeded, the operator should immedi-ately move the transmission range selector to the nextlower range and apply the service brakes until the truckis slowed to a speed which will permit the transmissionto downshift to the gear range selected.

A04017 1/92 Warnings and Cautions A4-1

The welding "Caution" plate WA9713 is located in thecab above the windshield. These instructions MUST befollowed when welding is done on the truck to avoiddamage to the ATEC components.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A ROPS/FOPS Warning plate is located on the rightside of the cab above the windshield. It specifies thatthe structure as manufactured meets SAE specifica-tions and warns that these specifications may be im-paired if subjected to any modifications or damage.

WA9779 Caution decal is located in the cab on the backof the sunvisor and specifies that during first four hoursof operation, the Truck Speed SHOULD NOT Exceed25 MPH (40 KPH) in order to properly break-in the oilbrake seals.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

On the right side of the operator’s instument panel is aseries of three Warnings.

The Warning on the left specifies that wheel brake lockis not to be used for parking. If engine is not running,brake pressure may bleed down allowing brakes to bereleased. It should be used only at the shovel or dump,or for emergency.

A4-2 Warnings and Cautions A04017 1/92

The center Warning specifies that if any of the red lightson the instrument panel are "ON" (during truck opera-tion), the truck should not be operated. The switch inthis panel is a manual test switch to check all indicatorlights for operation.

The Warning on the right specifies that when the slip-pery road control is in use, braking power to the frontwheels is reduced. The Slippery Road switch will notbe present on Haulpak® Trucks with rear oil-cooleddisc brakes.

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

WA6488 instruction decal is applied to the right sidewindow of the cab. It identifies the various symbols thatmay appear on the instrument panel and gauges. Referto Operator Controls, Section "N", for description offunction or control being identified by symbol.

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

WA9702 decal is located on top of the battery boxcover. The battery box is mounted on top of the rightdeck structure. This decal informs the technician thatthe truck electrical system is Negative Ground. If thebatteries are removed, proper polarity must be main-tained at installation. Always disconnect ground first.

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Attached to the exterior of the battery compartment isdanger plate WA9704. This plate stresses the need tokeep from making any sparks near the battery. Whengetting a battery assist from one truck to another, allswitches must be "Off" prior to making any connec-tions. Be certain to maintain correct polarity. Connectone lead of booster cable to 24V positive (+ ) post ofbattery needing assist, and other lead of the boostercable to the 24V positive (+ ) post of auxiliary battery.Connect one lead of second booster cable to 24Vnegative (-) post of auxiliary battery and then connectother lead of the booster cable to a good frame groundon the disabled truck away from the battery needingassist. This procedure will avoid the possibility of caus-ing sparks near the battery where explosive gases maybe present.

Sulfuric acid is corrosive and toxic. Use proper safetygear, goggles, rubber gloves and rubber apron whenhandling and servicing batteries.

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Warning plate WA9707 is mounted on top of the radia-tor grille near the radiator cap. Radiator pressuremust be released (refer to Radiator, Section "C"),before removing the radiator cap after engine hasbeen running. The engine cooling system is controlledby thermostats which keep coolant temperature be-tween 160o- 190oF (71o- 88oC) during operation. Hotcoolant may be expelled from the radiator resulting inserious scalding and burning if pressure is not releasedprior to removal of cap.


Decal WA9722 is located on the engine air cleanerwhich is on the deck above the right front wheel. Referto Section "C’ for air cleaner service.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Instructional decal WA9720 is located on a switch boxon the left side of the engine. The small toggle switchon top of the box disconnects both the 24 VDC and 12VDC from the ATEC system. The large "T" handle on theface of the switch box disconnects ALL electrical powerto the truck except the ATEC system when pulled outand rotated either direction from the horizontal posi-tion.

When disconnecting batteries, be certain that theATEC disconnect switch is "OFF" before physicallyremoving battery cables. Additionally, do not turnATEC switch "ON" before all battery connections aresecure.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Warning plates WA9705 are mounted on the frame infront of and to the rear of both front tires. Techniciansmaking adjustments are warned that the clearanceschange when the truck is steered. Serious injury bycrushing may occur if care is not taken.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

WA4990 Warning plate is located on the top of theparking brake actuator. It warns that the unit containsa spring with a preloaded force of 600 lb. (270 kg). Referto Parking Brake, Section "J" for service instructions.Serious injury may result if proper procedures are notfollowed.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .


WA9712 Warning plate is attached to both the hydrau-lic and fuel tank. For the safety of technicians who maybe working on the truck with the body in the raisedposition, they are warned to make sure safety pin(body-up retaining pin) is in position.

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Danger plate WA2892 is attached to each suspensioncylinder as well as steering and brake accumulators.This plate contains instructions for releasing internalpressure prior to disconnecting any hydraulic lines orhardware.

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

TY5888 Warning decal is applied to the Steering accu-mulator and both Brake accumulators to warn servic-ing personnel of both high gas pressure and hydraulicpressure. Be certain pressures are released beforedisconnecting any lines or disassembly of the cylin-ders. Refer to Sections "J" and "L" for accumulatorbleeddown instructions.

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

WA9719 hydraulic oil level check decal is located onthe hydraulic tank. The information given on this decalprovides the proper method of filling the hydraulic tank.If the steps are not followed closely, possible damageto hydraulic components may occur or possible injuryto the technician servicing the truck.

. . . . . . . . . . . . . . . . . . . . . . . . . . . .


WA9723 decal is located above the transmission filltube on front side of the hydraulic tank. It cautions theservicing technician to refer to the service manual forproper filling instructions to avoid serious damage tothe transmission.

VH8394 Identification plate is located on the right sideof the main frame, just in front of front wheel. Refer toserial number on this plate whenever reporting truckconditions.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . WA8875 Lubrication Chart is mounted on the front of the right front deck support. Refer to this chart for lubricationspecifications and lubrication intervals.


STANDARD CHARTS AND TABLES

This manual provides dual dimensioning for mostspecifications. U.S. standard units are specified first,with metric (SI) units in parentheses. Referencesthroughout the manual to standard torques or otherstandard values will be to one of the following Chartsor Tables. For values not shown in any of the charts ortables, standard conversion factors for most com-monly used measurements are provided in TABLE XIII,page A5-6.

INDEX OF TABLESTABLE I . . . . Standard Torque Chart (SAE) A5-1

TABLE II Standard Torque, 12-Point, Grade 9 A5-2

TABLE III . Standard Metric Assembly Torque A5-2

TABLE IV . . . . . JIC Swivel Nuts Torque Chart A5-3

TABLE V . . . . . . . . Pipe Thread Torque Chart A5-3

TABLE VI . . . . . . . . O-Ring Boss Torque Chart A5-3

TABLE VII . . . . O-Ring Face Seal Torque Chart A5-3

TABLE VIII . . Torque Conversions (ft.lbs -- N.m) A5-4

TABLE IX . Torque Conversions (ft.lbs -- kg.m) A5-4

TABLE X . . Pressure Conversions (psi -- kPa) A5-4

TABLE XI . . Pressure Conversions (psi -- MPa) A5-4

TABLE XII . . . . . . . . Temperature Conversions A5-5

TABLEXIII . . . Common Conversion Multipliers A5-6

EFFECT OF SPECIAL LUBRICANTS On Fasteners And Standard Torque Values

Haulpak Division does NOT recommend the use ofspecial "friction-reducing" lubricants such as, "CopperCoat", "Never Seize", and other similar products on thethreads of standard fasteners where "standard torque"values are applied.

The use of special "friction-reducing" lubricants willsignificantly alter the clamping force being applied tofasteners during the tightening process. If special "fric-tion-reducing" lubricants are used with the "StandardTorque" values listed below in Table I (and most Haul-pak service manuals), excessive stress and possiblebreakage of the fasteners may result.

Where Torque Tables specify "Lubricated Threads" forthe Standard Torque values listed, these standardtorque values are to be used with simple lithiumbase chassis grease (multi-purpose EP NLGI) or arust- preventive grease (see list, page A5-2) on thethreads and seats, unless specified otherwise.

NOTE: Always be sure threads of fasteners and tappedholes are free of burrs or other imperfections beforeassembling.

Standard Torque values are not to be used when"Turn-of-the-Nut" tightening procedures are rec-ommended.

CAP-SCREW

THREAD SIZE

TORQUE -- GRADE 5 TORQUE -- GRADE 8CAPSCREW

THREAD SIZE

TORQUE -- GRADE 5 TORQUE -- GRADE 8

ft. lbs. kg.m N.m ft. lbs. kg.m N.m ft. lbs. kg.m N.m ft. lbs. kg.m N.m

1/4--20 7 0.97 9.5 10 1.38 13.6 3/4--16 235 32.5 319 335 46.3 454

1/4--28 8 1.11 10.8 11 1.52 14.9 7/8--9 350 48.4 475 500 69.2 678

5/16--18 15 2.07 20.3 21 2.90 28 7/8--14 375 51.9 508 530 73.3 719

5/16--24 16 2.21 22 22 3.04 30 1.0--8 525 72.6 712 750 103.7 1017

3/8--16 25 3.46 34 35 4.84 47 1.0--12 560 77.4 759 790 109.3 1071

3/8--24 30 4.15 41 40 5.5 54 1.0--14 570 78.8 773 800 110.6 1085

7/16--14 40 5.5 54 58 8.0 79 1 1/8--7 650 89.9 881 1050 145 1424

7/16--20 45 6.2 61 62 8.57 84 1 1/8--12 700 96.8 949 1140 158 1546

1/2--13 65 9 88 90 12.4 122 1 1/4--7 910 125.9 1234 1480 205 2007

1/2--20 70 9.7 95 95 13.1 129 1 1/4--12 975 134.8 1322 1580 219 2142

9/16--12 90 12.4 122 125 17.3 169 1 3/8--6 1200 166 1627 1940 268 2630

9/16--18 95 13.1 129 135 18.7 183 1 3/8--12 1310 181 1776 2120 293 2874

5/8--11 125 17.3 169 175 24.2 237 1 1/2--6 1580 219 2142 2560 354 3471

5/8--18 135 18.7 183 190 26.2 258 1 1/2--12 1700 235 2305 2770 383 3756

3/4--10 220 30.4 298 310 42.8 420

TABLE ISTANDARD TORQUE CHART

SAE HEX HEAD CAPSCREW AND NUT ASSEMBLY(LUBRICATED THREADS)

TOLERANCES ± 10%GRADE 5 GRADE 8

A05001 10/96 Standard Torque Charts and Tables A5-1

Standard Assembly Torques For12-Point, Grade 9, Capscrews (SAE)

The following specifications appy to required assemblytorques for all 12-Point, Grade 9 (170,000 psi minimumtensile), Capscrews.

• Capscrew threads and seats SHALL be lubricatedwhen assembled.

Unless instructions specifically recommend oth-erwise, these standard torque values are to beused with simple lithium base chassis grease(multi-purpose EP NLGI) or a rust- preventivegrease (see list, this page) on the threads.

• Torques are calculated to give a clamping forceof approximately 75% of proof load.

• The maximum torque tolerance shall be ± 10% ofthe torque value shown.

TABLE II - STANDARD ASSEMBLY TORQUEfor 12-Point, Grade 9, Capscrews

CAPSCREW SIZE*

TORQUEft. lbs.

TORQUEN.m

TORQUEkg.m

0.250 - 20 12 16 1.7

0.312 - 18 24 33 3.3

0.375 - 16 42 57 5.8

0.438 - 14 70 95 9.7

0.500 - 13 105 142 14.5

0.562 - 12 150 203 20.7

0.625 - 11 205 278 28.3

0.750 - 10 360 488 49.7

0.875 - 9 575 780 79.4

1.000 - 8 860 1166 119

1.000 - 12 915 1240 126

1.125 - 7 1230 1670 170

1.125 - 12 1330 1800 184

1.250 - 7 1715 2325 237

1.250 - 12 1840 2495 254

1.375 - 6 2270 3080 313

1.375 - 12 2475 3355 342

1.500 - 6 2980 4040 411

1.500 - 12 3225 4375 445

* Shank Diameter (in.) - Threads per in.

This Table represents standard values only. Do not use these values to replace torque values which are

specified in assembly instructions.

Standard Metric Assembly Torque ForClass 10.9 Capscrews & Class 10 Nuts

The following specifications appy to required assemblytorques for all meteric Class 10.9 finished hexagonhead capscrews and Class 10 nuts.

• Capscrews threads and seats SHALL NOT belubricated when assembled. These specificationsare based on all capscrews, nuts, and hardenedwashers being phosphate and oil coated.NOTE: If zinc-plated hardware is used, eachpiece must be lubricated with a Rust PreventiveGrease or Lithium-base grease to achieve thesame clamping forces provided below.

• Torques are calculated to give a clamping forceof approximately 75% of proof load.

• The maximum torque tolerance shall be within± 10% of the torque value shown.

TABLE III - STANDARD METRIC ASSEMBLY TORQUE

CAPSCREW SIZE*

TORQUEN.m

TORQUEft. lbs.

TORQUEkg.m

M 6 x 1 12 9 1.22

M 8 x 1.25 30 22 3.06

M10 x 1.5 55 40 5.61

M12 x 1.75 95 70 9.69

M14 x 2 155 114 15.81

M16 x 2 240 177 24.48

M20 x2.5 465 343 47.43

M24 x 3 800 590 81.6

M30 x 3.5 1600 1180 163.2

M36 x 4 2750 2028 280.5

* Shank Diameter (mm) x Threads per mm.

This Table represents standard values only. Do not use these values to replace torque values which are

specified in assembly instructions.

SUGGESTED* SOURCES FOR RUST PREVENTIVE GREASE:

• AMERICAN ANTI-RUST GREASE # 3-X fromStandard Oil Company (also American Oil Co.)

• GULF NORUST # 3 from Gulf Oil Company.

• MOBILARMA 355, Product No. 66705 from Mobil Oil Corporation.

• RUST BAN 326 from Humble Oil Company.

• RUSTOLENE B GREASE from Sinclair Oil Company.

• RUST PREVENTIVE GREASE - CODE 312 fromthe Southwest Grease and Oil Company.

* NOTE: This list represents the current Engineeringapproved sources for use in Haulpak manufacture. Itis not exclusive. Other products may meet the samespecifications of this list.

A5-2 Standard Torque Charts and Tables A05001 10/96

TABLE IVTORQUE CHART FOR JIC 37° SWIVEL NUTS

WITH OR WITHOUT O-RING SEAL

SIZECODE

TUBE SIZE(O.D.)

THREADSUNF -- 2B

TORQUEFT. LBS.

-- 2 0.125 0.312--24 4 ± 1

-- 3 0.188 0.375--24 8 ± 3

-- 4 0.250 0.438--20 12 ± 3

-- 5 0.312 0.500--20 15 ± 3

-- 6 0.375 0.562--18 18 ± 5

-- 8 0.500 0.750--16 30 ± 5

-- 10 0.625 0.875--14 40 ± 5

-- 12 0.750 1.062--12 55 ± 5

-- 14 0.875 1.188--12 65 ± 5

-- 16 1.000 1.312--12 80 ± 5

-- 20 1.250 1.625--12 100 ± 10

-- 24 1.500 1.875--12 120 ± 10

-- 32 2.000 2.500--12 230 ± 20

TABLE VTORQUE CHART FOR

PIPE THREAD FITTINGS

SIZECODE

PIPE THREADSIZE

WITHSEALANTFT. LBS.

WITHOUTSEALANTFT. LBS.

-- 2 0.125--27 15 ± 3 20 ± 5

-- 4 0.250--18 20 ± 5 25 ± 5

-- 6 0.375--18 25 ± 5 35 ± 5

-- 8 0.500--14 35 ± 5 45 ± 5

-- 12 0.750--14 45 ± 5 55 ± 5

-- 16 1.000--11.50 55 ± 5 65 ± 5

-- 20 1.250--11.50 70 ± 5 80 ± 5

-- 24 1.500--11.50 80 ± 5 95 ± 10

-- 32 2.000--11.50 95 ± 10 120 ± 10

TABLE VITORQUE CHART FOR

O-RING BOSS FITTINGS

SIZECODE

TUBE SIZE(O.D.)

THREADSUNF -- 2B

TORQUEFT. LBS.

-- 2 0.125 0.312--24 4 ± 2

-- 3 0.188 0.375--24 5 ± 2

-- 4 0.250 0.438--20 8 ± 3

-- 5 0.312 0.500--20 10 ± 3

-- 6 0.375 0.562--18 13 ± 3

-- 8 0.500 0.750--16 24 ± 5

-- 10 0.625 0.875--14 32 ± 5

-- 12 0.750 1.062--12 48 ± 5

-- 14 0.875 1.188--12 54 ± 5

-- 16 1.000 1.312--12 72 ± 5

-- 20 1.250 1.625--12 80 ± 5

-- 24 1.500 1.875--12 80 ± 5

-- 32 2.000 2.500--12 96 ± 10

TABLE VIITORQUE CHART FOR

O-RING FACE SEAL FITTINGS

SIZECODE

TUBE SIZE(O.D.)

THREADSUNF -- 2B

TORQUEFT. LBS.

-- 4 0.250 0.438--20 11 ± 1

-- 6 0.375 0.562--18 18 ± 2

-- 8 0.500 0.750--16 35 ± 4

-- 10 0.625 0.875--14 51 ± 5

-- 12 0.750 1.062--12 71 ± 7

-- 16 1.000 1.312--12 98 ± 6

-- 20 1.250 1.625--12 132 ± 7

-- 24 1.500 1.875--12 165 ± 15


TABLE VIII TORQUE CONVERSIONSFoot Pounds -- ft. lbs. To Newton.meters (N.m)

FT. LBS. 0 1 2 3 4 5 6 7 8 9

0 (N.m) 1.36 2.71 4.07 5.42 6.78 8.14 9.49 10.85 12.20

10 13.56 14.91 16.27 17.63 18.98 20.34 21.69 23.05 24.40 25.76

20 27.12 28.47 29.83 31.18 32.54 33.90 35.25 36.61 37.96 39.32

30 40.67 42.03 43.39 44.74 46.10 47.45 48.81 50.17 51.52 52.87

40 54.23 55.59 56.94 58.30 59.66 61.01 62.37 63.72 65.08 66.44

50 67.79 69.15 70.50 71.86 73.21 74.57 75.93 77.28 78.64 80.00

60 81.35 82.70 84.06 85.42 86.77 88.13 89.48 90.84 92.20 93.55

70 94.91 96.26 97.62 98.97 100.33 101.69 103.04 104.40 105.75 107.11

80 108.47 109.82 111.18 112.53 113.89 115.24 116.60 117.96 119.31 120.67

90 122.03 123.38 124.74 126.09 127.45 128.80 130.16 131.51 132.87 134.23

See NOTE on page A5-5

TABLE IX TORQUE CONVERSIONSFoot Pounds -- ft. lbs. To kilogram.meter (kg.m)

FT. LBS. 0 1 2 3 4 5 6 7 8 9

0 (kg.m) 0.138 0.277 0.415 0.553 0.692 0.830 0.968 1.106 1.245

10 1.38 1.52 1.66 1.80 1.94 2.07 2.21 2.35 2.49 2.63

20 2.77 2.90 3.04 3.18 3.32 3.46 3.60 3.73 3.87 4.01

30 4.15 4.29 4.43 4.56 4.70 4.84 4.98 5.12 5.26 5.39

40 5.53 5.67 5.81 5.95 6.09 6.22 6.36 6.50 6.64 6.78

50 6.92 7.05 7.19 7.33 7.47 7.61 7.74 7.88 8.02 8.16

60 8.30 8.44 8.57 8.71 8.85 8.99 9.13 9.27 9.40 9.54

70 9.68 9.82 9.96 10.10 10.23 10.37 10.51 10.65 10.79 10.93

80 11.06 11.20 11.34 11.48 11.62 11.76 11.89 12.03 12.17 12.30

90 12.45 12.59 12.72 12.86 13.00 13.14 13.28 13.42 13.55 13.69


TABLE X PRESSURE CONVERSIONSPounds/sq. in. [psi] To kilopascals (kPa)

Formula: psi x 6.895 = kPa

PSI 0 1 2 3 4 5 6 7 8 9

0 (kPa) 6.895 13.79 20.68 27.58 34.47 41.37 48.26 55.16 62.05

10 68.95 75.84 82.74 89.63 96.53 103.42 110.32 117.21 124.1 131.0

20 137.9 144.8 151.7 158.6 165.5 172.4 179.3 186.2 193.1 200.0

30 206.8 213.7 220.6 227.5 234.4 241.3 248.2 255.1 262.0 268.9

40 275.8 282.7 289.6 296.5 303.4 310.3 317.2 324.1 331.0 337.9

50 344.7 351.6 358.5 365.4 372.3 379.2 386.1 393.0 399.9 406.8

60 413.7 420.6 427.5 434.4 441.3 448.2 455.1 462.0 468.9 475.8

70 482.6 489.5 496.4 503.3 510.2 517.1 524.0 530.9 537.8 544.7

80 551.6 558.5 565.4 572.3 579.2 586.1 593.0 599.9 606.8 613.7

90 620.5 627.4 634.3 641.2 648.1 655.0 661.9 668.8 675.7 682.6


TABLE XI PRESSURE CONVERSIONSPounds/sq. in. [psi] To Megapascals (MPa)

Formula: psi x 0.0069 = MPa

PSI 0 10 20 30 40 50 60 70 80 90

0 (MPa) 0.069 0.14 0.21 0.28 0.34 0.41 0.48 0.55 0.62

100 0.69 0.76 0.83 0.90 0.97 1.03 1.10 1.17 1.24 1.31

200 1.38 1.45 1.52 1.59 1.65 1.72 1.79 1.86 1.93 2.00

300 2.07 2.14 2.21 2.28 2.34 2.41 2.48 2.55 2.62 2.69

400 2.76 2.83 2.90 2.96 3.03 3.10 3.17 3.24 3.31 3.38

500 3.45 3.52 3.59 3.65 3.72 3.79 3.86 3.93 4.00 4.07

600 4.14 4.21 4.27 4.34 4.41 4.48 4.55 4.62 4.69 4.76

700 4.83 4.90 4.96 5.03 5.10 5.17 5.24 5.31 5.38 5.45

800 5.52 5.58 5.65 5.72 5.79 5.86 5.93 6.00 6.07 6.14

900 6.21 6.27 6.34 6.41 6.48 6.55 6.62 6.69 6.76 6.83



NOTE: Tables such as Table VIII, IX, X, and XI may be used as in the following example:

Example: Convert 975 psi to kilopascals (kPa).

1. Select Table VIII.

2. Go to PSI row 90, column 7; read 668.897 psi = 668.8 kPa.

3. Multiply by 10:970 psi = 6688 kPa.

4. Go to PSI row 0, column 5; read 34.475 psi = 34.47 kPa. Add to step 3.

5. 970 + 5 psi = 6688 + 34 = 6722 kPa.975 psi = 6722 kPa.

TABLE XII TEMPERATURE CONVERSIONSFORMULA: F° -- 32 ÷ 1.8 = C° C° x 1.8 + 32 = F°

CELSIUSC°

FAHRENHEITF°

CELSIUSC°

FAHRENHEITF°

CELSIUSC°

FAHRENHEITF°

121 250 482 63 145 293 4 40 104

118 245 473 60 140 284 2 35 95

116 240 464 57 135 275 -- 1 30 86

113 235 455 54 130 266 -- 4 25 77

110 230 446 52 125 257 -- 7 20 68

107 225 437 49 120 248 -- 9 15 59

104 220 428 46 115 239 -- 12 10 50

102 215 419 43 110 230 -- 15 5 41

99 210 410 41 105 221 -- 18 0 32

96 205 401 38 100 212 -- 21 -- 5 23

93 200 392 35 95 293 -- 23 -- 10 14

91 195 383 32 90 194 -- 26 -- 15 5

88 190 374 29 85 185 -- 29 -- 20 -- 4

85 185 365 27 80 176 -- 32 -- 25 -- 13

82 180 356 24 75 167 -- 34 -- 30 -- 22

79 175 347 21 70 158 -- 37 -- 35 -- 31

77 170 338 18 65 149 -- 40 -- 40 -- 40

74 165 329 15 60 140 -- 43 -- 45 -- 49

71 160 320 13 55 131 -- 46 -- 50 -- 58

68 155 311 10 50 122 -- 48 -- 55 -- 67

66 150 302 7 45 113 -- 51 -- 60 -- 76

NOTE: The numbers in the unmarked columns refer to temperature in either degrees Celsius (C°) or Fahrenheit, F°. Select a number inthis unmarked column and read to the left to convert to degrees Celsius (C°) or read to the right to convert to degrees Fahrenheit, F°. If starting with a known temperature (either C° or F°), find that temperature in the marked column and read the converted temperature inthe center, unmarked column.


TABLE XIII -- COMMON CONVERSION MULTIPLIERS

COMMON CONVERSION MULTIPLIERSENGLISH to METRIC

TO CONVERT FROM TO

MULTIPLYBY

inch -- in. millimeter (mm) 25.40

inch -- in. centimeter (cm) 2.54

foot -- ft. meter (m) 0.3048

yard -- yd. meter (m) 0.914

mile -- mi. kilometer (km) 1.61

sq. in. -- in.2 sq. centimeters (cm2) 6.45

sq. ft. -- ft.2 sq. centimeters (cm2) 929

cu. in. -- in.3 cu. centimeters (cm3) 16.39

cu. in. -- in.3 liters (l) 0.016

cu. ft. -- ft.3 cu. meters (m3) 0.028

cu. ft. -- ft.3 liters (l) 28.3

ounce -- oz. kilogram (kg) 0.028

fluid ounce -- fl. oz. milliliter (ml) 29.573

pound (mass) kilogram (kg) 0.454

pound (force) -- lbs. Newton (N) 4.448

in. lbs. (force) Newton.meters (N.m) 0.113

ft. lbs. (force) Newton.meters (N.m) 1.356

ft. lbs. (force) kilogram.meters (kg.m) 0.138

kilogram.meters (kg.m) Newton.meters (N.m) 9.807

psi (pressure) kilopascals (kPa) 6.895

psi (pressure) megapascals (MPa) 0.007

psi (pressure) kilograms/cm2 (kg/cm2) 0.0704

ton (short) kilogram (kg) 907.2

ton (short) metric ton 0.907

quart -- qt. liters (l) 0.946

gallon -- gal. liters (l) 3.785

HP (horsepower) Watts 745.7

HP (horsepower) kilowatts (kW) 0.745

COMMON CONVERSION MULTIPLIERSMETRIC to ENGLISH

TO CONVERT FROM TO

MULTIPLYBY

millimeter (mm) inch -- in. 0.0394

centimeter (cm) inch -- in. 0.3937

meter (m) foot -- ft. 3.2808

meter (m) yard -- yd. 1.0936

kilometer (km) mile -- mi. 0.6210

sq. centimeters (cm2) sq. in. -- in.2 0.1550

sq. centimeters (cm2) sq. ft. -- ft.2 0.001

cu. centimeters (cm3) cu. in. -- in.3 0.061

liters (l) cu. in. -- in.3 61.02

cu. meters (m3) cu. ft. -- ft.3 35.314

liters (l) cu. ft. -- ft.3 0.0353

grams (g) ounce -- oz. 0.0353

milliliter (ml) fluid ounce -- fl. oz. 0.0338

kilogram (kg) pound (mass) 2.2046

Newton (N) pound (force) -- lbs. 0.2248

Newton.meters (N.m) kilogram.meters (kg.m) 0.102

Newton.meters (N.m) ft. lbs. (force) 0.7376

kilogram.meters (kg.m) ft. lbs. (force) 7.2329

kilogram.meters (kg.m) Newton.meters (N.m) 9.807

kilopascals (kPa) psi (pressure) 0.1450

megapascals (MPa) psi (pressure) 145.038

kilograms/cm2 (kg/cm2) psi (pressure) 14.2231

kilograms/cm2 (kg/cm2) kilopascals (kPa) 9.8068

kilogram (kg) ton (short) 0.0011

metric ton ton (short) 1.1023

liters (l) quart -- qt. 1.0567

liters (l) gallon -- gal. 0.2642

Watts HP (horsepower) 0.00134

kilowatts (kW) HP (horsepower) 1.3410


STORAGE AND IDLE MACHINE PREPARATION

There may be periods when it is necessary for amachine to be idle for an extended period of time.Properly prepared, a stored machine may promptlyand safely be put back into operational service. Im-proper preparation, or complete lack of preparation,can make the job of getting the vehicle back to oper-ating status difficult.

The following information outlines the essential propersteps for preparing a unit for extended storage, andthe necessary steps to bring it back to operationalstatus - these are the ideals. Additional information isgiven to help restore those machines which were notput into storage, merely shut down and left idle for along period of time.

Much of this material is of a general nature since theenvironment, where the machine has been standingidle, will play a big part in its overall condition. Hot,humid climate will affect vehicle components muchdifferently than the dry desert atmosphere or a coldarctic environment. These climatic aspects must beconsidered, and appropriate actions taken when re-storing a long term idle vehicle.

These instructions are not intended to be all inclusive,but are furnished to provide the minimum guide lines.The final aim should always be to provide the operatorwith a safe, fully productive vehicle, that he can relyon.

SHORT TERM IDLE PERIODS

There will be periods when a vehicle may be idle from30-60 days, but must be ready for use at all times.

The most effective handling of this type situation is tofollow the procedure given below to prevent any dete-rioration from beginning.

1. Keep the vehicle fully serviced.

2. On a weekly schedule, perform a visual check ofthe vehicle, start and run the engine until both theengine and transmission are up to operating tem-perature. Move the vehicle around the yard for afew minutes to insure that all internal gears andbearings are freshly lubricated.

3. Operate all hydraulic functions through completerange to insure that cylinder rams and all sealsare fully lubricated.

4. Check and operate all systems.

5. After shutdown, drain air tank (if so equipped) toexpel any accumulated moisture.

6. Once a month, perform the 10 hour service itemsshown in the Operation and Maintenance Manu-als. Keep batteries properly serviced.

A07002 1/98 STORAGE PROCEDURES A7-1

PREPARATION FOR STORAGE

For long term idle periods, proper preparation will paylarge dividends in time and money when future opera-tion of the vehicle is scheduled.

1. Engine should be prepared for storage accordingto instructions found in the engine manufacturersmanual.

2. Transmission should be prepared for storage.Instruction will be found in the transmission Serv-ice Manual. Several storage variations are given.

3. The vehicle should be in top operating conditionwith all discrepancies corrected. Paint should bein good condition, no rust or corrosion, all ex-posed, machined or unpainted surfaces shouldbe coated with a good rust preventative grease.

4. After the vehicle has been parked in its storagelocation, all hydraulic cylinders, including Hydrairsuspensions (Trucks), should be retracted asmuch as possible (steering cylinders centered).Wipe the exposed portion of all cylinder ramsclean and, coat (including seals on ends of barrel)with good preservative grease.

5. If long term storage is anticipated, the vehicleshould be blocked up with the tires clear of theground or floor to remove vehicle weight from thetires. Lower air pressure in the tires to 15-25 psi(103-172 kPa). Completely cover the tires withtarpolins to minimize rubber oxidation and dete-rioration.

6. (Trucks equipped with air-actuated park brake)With air tanks pressurized and parking brakevalve "Off", remove a clevis pin from the brakeactuator linkage. This will relieve spring pressurefrom applying the parking brake while the vehicleis idle. Replace clevis pin in link to prevent loss.Tag steering wheel with a parking brake discon-nected tag.

7. Drain air tank(s) completely (if equipped). Whentank compartments are empty, fog the inside ofeach tank compartment with a light application ofpreservative oil to deter rust and corrosion.

8. Clean the radiator; refer to Engine Service Manualand the Vehicle Service Manual for the propercleaning instructions.

9. The cooling system should be completely drained,chemically flushed, and refilled with a conditionedwater/antifreeze solution suitable for the lowesttemperature anticipated. Refer to Section "P", Fluid Specifications andCharts, of the Shop Manual for the proper anti-freeze and conditioner concentrations. After refill-ing the system, always operate the engine untilthe thermostats open to circulate the solutionthrough the cooling system.

NOTE: NEVER store a vehicle with a dry coolingsystem.

10. New hydraulic filters should be installed and thehydraulic tank fully serviced with Type C-4 oil asspecified in Section "P", Lubrication and Service,of the Shop Manual.

Any operating fluid, such as hydraulic oil, escap-ing under pressure can have sufficient force toenter a person’s body by pentrating the skin. Seri-ous injury and possible death may result if propermedical treatment by a physician familiar with thisinjury is not received immediately.

11. Disconnect batteries, If possible, batteries shouldbe removed and stored in a battery shop or a cooldry location on wooden blocks. Do not store bat-teries on a concrete floor. Clean battery compart-ment, remove all corrosion and paint compartmentwith acid proof paint.

12. Wheel axle housings and final drives should befully serviced with prescribed lubricants. Seal allvents.

A7-2 STORAGE PROCEDURES A07002 1/98

13. Exhaust openings and air cleaners should becovered tightly with moisture barrier paper andsealing tape.

14. All lubrication points (grease fittings) should beserviced with the prescribed lubricants.

15. Relieve tension from all drive belts. The enginemanufacturer recommends insertion of heavykraft paper between belts and pulleys to preventsticking.

16. All vandalism covers and locks should be in placeand secured.

17. If so equipped, cab windows should be closed,locked and sealed and the cab door locked toprevent vandalism and weather effects.

18. The vehicle fuel tanks should be completelydrained of fuel, fogged with preservative lubricant,("NOX-RUST" MOTOR STOR., SAE10) andclosed tightly. All fuel filters should be replaced.

19. If at all possible, to aid those who will eventuallyplace the unit back in operation, all available serv-ice publications (vehicle, engine and transmis-sion) and a current parts catalog should bepackaged in a moisture proof package and placedin the vehicle cab.

20. Be certain water drain holes in body (trucks) areopen.

REMOVAL FROM STORAGE

If the foregoing preparations were conscientiously fol-lowed in placing the vehicle into storage, getting it backto operational status is a simple matter of reversingthese steps.

NOTE: Before starting the job or restoring a vehicle tooperation, obtain copies of the Operation and Mainte-nance Manual, Shop Manual, Engine and Transmis-sion Manuals and/or the Parts Book and follow ALLspecial instructions regarding servicing the vehicle andits components.

In addition to removing the storage materials, thefollowing actions should be taken.

1. Inspect the entire vehicle carefully for rust andcorrosion, correct as necessary.

2. Service the engine according to the Engine Manu-facturer’s Operation and Maintenance Manual.

3. Clean the radiator; refer Engine Manufacturer’sOperation and Maintenance Manual.

4. The cooling system should be completely drained,chemically flushed, and refilled with a conditionedwater/antifreeze solution suitable for the lowesttemperature anticipated. Refer to Fluid Specifi-cations in Section "P", Lubrication and Service,of the Shop Manual for the proper anti-freeze andconditioner concentrations. After refilling the sys-tem, always operate the engine until the thermo-stats open to circulate the solution through thecooling system.

5. Refer to the proper transmission service manualfor returning the transmission to operation.

6. Thoroughly inspect all drive belts, hydraulic, airand oil lines for evidence of damage, wear ordeterioration. Replace any suspected lines. Don’ttake chances on ruptures or blow-outs.

7. New hydraulic filters should be installed and thehydraulic tank (reservoir) checked and servicedwith Type C-4 oil as specified in Section "P",Lubrication and Service, of the Shop Manual.

8. Drain on fuel tank should be opened to removeany build up of moisture or sediment that mayhave accumulated while in storage. Close drainthen fill the fuel tank with approved diesel fuel.

NEVER blend gasoline, gasohol and/or alcoholwith diesel fuel. This practice creates an extremeFIRE HAZARD and under certain conditions maycause an EXPLOSION.

9. Make certain that all hydraulic controls, steeringlinkage and throttle linkage points are lubricatedand operate freely before engine start up.

10. All electrical connections must be clean and tight.Check security of all ground straps and cables.


11. Install fully charged batteries in unit. Clean con-nectors and connect battery cables. Compartmentmust be free of corrosion. Secure batteries withhold downs.

12. Check all electrical cables for weathering, cracksand/or damage. Replace any defective cables.

Air pressure must be released from tires with badcuts or wear that extends into the plies, beforeremoval from the vehicle. Also, do not allow per-sonnel to stand in removal path of tires.

13. Check all tires carefully for serviceability and in-flate to proper pressure.

14. If disconnected, reconnect the parking brake link-age.

15. Completely service the vehicle as recommendedin Section "P", Lubrication and Service, of theShop Manual for both 10 and 100 hour inspec-tions.

16. Adjust all drive belts to specified tension.

17. Make certain that all hydraulic controls, steeringlinkage and throttle linkage points are free beforeengine start up.

18. Use the Operation and Maintenance Manual forguidance on engine start and vehicle checkout.Make a thorough check of all hose and line con-nections for leakage when the engine is running.

19. Before moving the vehicle, cycle all hydrauliccontrols and steering to verify proper operation.Verify proper operation of service brakes, emer-gency braking system and parking brake. CheckALL system instruments to insure that all systemsare operational. (Trucks with air-over-hydraulic brakes.) Bleed air system down with brake pedal applica-tions to insure that the air governor is functioningproperly.

Consult the service manual for the specific truckbeing serviced. Verify proper operation of the aircompressor, the air governor, and the air tanksafety valve. If any of these components do notfunction as prescribed in the service manual,shut down engine and correct any discrepancybefore continuing operation.

20. When all systems are operational and all discrep-ancies are corrected, road test the vehicle in asmooth, level, unobstructed area (with qualified,experienced operator only) to check steering re-sponse, transmission shifting, service brake effi-ciency, and hydraulic functions. Only when it isassured that the vehicle is in safe operationalcondition should it be turned over to an operator.

21. Fire protection equipment on a machine which hasbeen in storage should be recharged before themachine is returned to service.


RECONDITIONING AN IDLE VEHICLE

NEVER attempt operation of a vehicle which hasbeen standing idle for a long period until all sys-tems which affect steering, brakes, engine, trans-mission and running gear have been completelyreconditioned. An unsafe vehicle can cause seri-ous injuries and/or major property damage -DON’T TAKE CHANCES!

At times a vehicle is subjected to long idle periodswithout being properly serviced for storage - merelyshut down and left to the elements for an extendedperiod. Reconditioning of this vehicle can and doespresent a major expenditure of time and money whenit is to be put into operating condition.

1. Remove all trash and thoroughly clean the vehiclebefore starting any inspection or maintenance.

2. Remove vehicle batteries and move to batteryshop for service and charging or replacement asnecessary.

Do not disassemble an inflated tire. Remove valvecore slowly, and allow pressure to bleed off, beforeattempting to remove lockring. Also, eye protec-tion should be worn during tire deflation to protectagainst any foreign object being projected into theeyes.

3. Inspect tires thoroughly for tread and side wallcondition, weathering, cuts and cracks.

a. Any tire suspected of being unserviceableshould be dismounted and thoroughly in-spected inside and out before being inflated.

Do not mix rim parts of different rim manufactur-ers. Rim parts may resemble those of a differentmanufacturer, but the required tolerances may bewrong. Use of mismatched rim parts is hazardous.

b. If tires are dismounted, all wheel componentsmust be cleaned, inspected, all rust and corro-sion removed and parts repainted as applica-ble before remounting the tires. Follow thesafety rules when mounting and inflating tires.

c. Mount and inflate tires as shown in Operationand Maintenance Manual or service manual.

4. Inspect vehicle service brakes carefully.

Before disabling the brake circuit, block all wheelsto prevent possible movement of the vehicle.

a. If dust covers are installed on the inboard sideof the wheels, remove the covers to allow forinspection of brake calipers/shoes and/orbrake discs/drums.

The use of vapor degreasing or steam cleaning isnot recommended, either for brake assemblies orthe component parts. Corrosion and rusting mayoccur.

b. All brake lines, connections and pressure con-verters must be clean, serviced and free of rustand corrosion.

c. Check condition of brake fluid; fill or replacefluid as necessary.


5. Inspect air system components (if equipped) forcorrosion and deterioration.

a. Safety valve plunger must be free. Removerubber cap from air governor to check for anycorrosion and rust. Governor should be re-placed if any defect is suspected.

b. Air compressor should turn by hand withoutappreciable binding. Check and tighten drivebelts to prescribed tension; if one belt of a setis unserviceable, replace the set.

c. If internal air tank corrosion is suspected, thedrain cocks of the dual air tank should beopened or removed and the automatic mois-ture ejector removed from the tank.

d. Disconnect the tank line from the compressorand connect a shop air line to the tank line.Slowly apply shop pressure to the system whileobserving the openings in the tanks. If excessmoisture, dirt, rust or other foreign material isejected from tanks, the complete air systemshould be reconditioned, including replace-ment of suspect components. Air tanks cannotbe easily checked for wall thickness; if rust orcorrosion is present in the tank, replacement ofthe tank should be considered.

e. If contamination is eliminated as a possibleproblem, shop air may be used to charge airsystem and check all air operated componentsexcept the compressor and governor.

f. Treadle valves must operate smoothly andshow no internal or external damage or con-tamination. Leakage limitations are shown inSection "J", Brake System, of the Shop Man-ual.

g. The throttle cylinder and parking brake actuatormust cycle smoothly when actuated by thetreadle valves or parking brake valve.

h. When air system servicing is complete and alldefective components repaired or replaced,the service brake hydraulic circuits should bebled according to instructions in Section "J",Brake System, of the Shop Manual.

6. The vehicle engine should be inspected and serv-iced according to the Engine Manufacturer’s Op-eration And Maintenance Manuals.

a. Insure that exhaust is clear and clean, no for-eign materials. If water entry is suspected,disconnect air tubes at the turbochargers tocheck for water damage before attemptingstartup.

b. Replace fuel filters, fill filter cans with fresh fuelfor engine priming.

Have a new safety filter (secondary) filter elementon hand before removing old one. Do not keepintake system open to atmosphere any longer thanabsolutely necessary.

c. Remove and replace both the primary andsafety filter (secondary) elements in the aircleaners. Check all intake lines between aircleaners and engine. All clamps must be tight.Indicating plunger in filter condition indicatorsmust be free.

d. The tubes in precleaner section of air cleanerassembly should be inspected, all tubes shouldbe clear and clean. Use a light to inspect thetubes. The light should be visible. If clogging isevident, precleaner must be cleaned. Cleanprecleaner according to instructions in Section"C", of the Shop Manual.

e. Drain and flush engine cooling system. Fill withcoolant and inhibitors after checking all lines,hoses and connections. Refer to Section "P",Lubrication and Service, of the Shop Manual,for anti-freeze recommendations. Radiatorcores must be clear of dirt and trash.

To prevent injuries, always release spring tensionbefore replacing the fan belt.

f. Check and tighten engine fan drive belts, installnew belt set if necessary.

g. Check and tighten engine mounts.

7. Inspect and service the transmission (mechanicaldrive vehicles) according to the Transmissionmanufacturer’s service manual.

NOTE: If hydraulic pump or engine is inoperative,dump body (trucks) should be raised with a crane sobody holding devices can be installed.

a. Check all transmission electrical connectionsfor corrosion, cleanliness and tightness. Checkelectrical cables for weathering, damage andproper clamping.

b. Check drive lines for tightness of hardware andworn U-joints.

c. Check transmission mounts for condition andsecurity.


8. If fuel was left in the tanks, it must be removed.Do not attempt to use old diesel fuel.

a. With tanks empty, remove inspection platesand thoroughly check interior of tanks; clean ifnecessary to remove sediment and contamina-tion. If fuel was contaminated, lines should bedisconnected and blown clear.

b. Check all fuel lines for deterioration or damage.Replace lines as necessary.

c. Replace inspection covers, use new gaskets.

d. Service tanks with specified diesel fuel.

e. Replace fuel filters.

Any operating fluid, such as hydraulic oil or brakefluid escaping under pressure, can have sufficientforce to enter a person’s body by penetrating theskin. Serious injury and possible death may resultif proper medical treatment by a physican familiarwith this injury is not received immediately.

9. Hydraulic tank should be drained. If oil is notcontaminated and is stored in clean containers, itmay be reused if filtered through 3-micron filterelements when being pumped back into the tank.Do not attempt to use contaminated hydraulic oil,especially if water entry into the system is sus-pected.

NOTE: If filling is required, use clean hydraulic oil only.Refer to the Lubrication chart in Section "P", Lubrica-tion and Service, of the Shop Manual for proper oilspecifications.

a. Replace hydraulic filter elements and cleansuction strainer elements. While suction strain-ers are removed, inspect and clean interior oftank thoroughly to remove all sediment andforeign material.

b. Inspect all hydraulic lines for deterioration ordamage. Replace suspected lines - don’t riskhose ruptures or blow outs.

c. Check all hydraulic components - pumps,valves and cylinders for damage and corro-sion. Secure all mountings and connections.Control valves in the cab must be free movingwith no binding.

d. Check exposed portions of all hydraulic cylin-der rams for rust, pitting and corrosion. If plat-ing is deteriorated, the cylinder should beremoved and overhauled or replaced; pitted orscored plating will cause leakage at the cylin-der seals.

10. Check front wheel hub, final drive and wheel axlelubricant. If contamination is suspected, oil shouldbe drained completely and the component serv-iced with clean prescribed lubricant. If major con-tamination is present, disassembly and overhaulwill be in order.

11. Check parking brake. Since it is spring applied, thebrake shoes/pads may be stuck tightly to thedrum/disc, it may be necessary to remove andoverhaul the parking brake assembly.

12. Lubricate all grease fittings with prescribed lubri-cants which are not part of the automatic lubrica-tion system. Pay particular attention to thesteering linkage connections. All pivot points mustbe free of any binding.

13. Check generator/alternator for corrosion or dete-rioration. Generator/alternator rotor must be free,with no binding or roughness. Inspect, install andproperly tension the generator/alternator drivebelts.

14. Check security of steering cylinder ball joints linkand hydraulic connections.

15. Examine Hydrair suspensions (trucks) for signs ofdamage.

a. Discharge nitrogen from suspensions as out-lined in the service manual. Check conditon ofsuspension oil and cylinder wipers. If wipersare cracked or hardened, the suspension mustbe rebuilt. Recharge suspension with new oil ifold oil is deteriorated.

b. Check exposed chrome portions of cylinder forrust, pitting and corrosion. If plating is deterio-rated the suspension should be removed andoverhauled or replaced; pitted or scored platingwill rapidly cause leakage at the seals.

c. Recharge suspensions as outlined in the serv-ice manual.

16. If not previously done, install fully charged batter-ies and completely charge air tank (if equipped)with shop air.


ENGINE OPERATION

Insure that all tools and loose equipment havebeen removed prior to engine start-up. Sound hornprior to engine start. Make sure emergency shutdown is reset. Cables must be free moving in theirhousings.

When all reconditioning operations have been com-pleted, a static check of engine operation along withoperation of systems as well as verification of brakingand steering must be done before the vehicle ismoved.

1. Insure all personnel are clear of Equipment beforestarting engine. Always sound the horn as awarning before actuating any operational con-trols.

Before starting engine, clear the immediate area ofpersonnel and obstructions.

Never start the engine in a building unless thedoors and windows are open and ventilation isadequate.

2. Turn key switch "On". Warning lights for low air,brake, and steering pressure should illuminateand the horn should sound. If it does not, checkall components in the circuit (both air and electri-cal) and correct the discrepancy before continu-ing.

3. Turn key switch to start position to crank engine,release switch when engine fires. Watch engineoil pressure gauge; if pressure does not show in10 - 15 seconds, shut down and locate problem.On air throttle engines, there will be no throttlecontrol until air pressure builds, engine should runabout 1000 RPM.

4. While engine is warming up, make a carefulinspection of engine coolant, oil and fuel lines forleaks. Check hydraulic pump for leakage as wellas all hydraulic lines. Mechanical Drive vehicles -- Check transmissionand retarder cooler lines and aftercooler for leak-age. If leakage is evident, shut down and correctbefore continuing checkout. Listen for unusualsounds, which may indicate problems in compo-nents.

5. When engine is up to operating temperature,check operation of throttle circuit; accelerationshould be smooth. Keep a close watch on thegauges for any abnormal activity. Proper tem-peratures and pressures are shown in the Opera-tion and Maintenance Manual.


AFTER ENGINE HAS STARTEDAny machine which is unsafe and/or not in top operat-ing condition should not be assigned to an operator forproduction use.

1. Become thoroughly familiar with steering andemergency controls. Test the steering in extremeright and left directions. If the steering system isnot operating properly, shut engine down imme-diately. Determine the steering system problemand have repairs made before resuming opera-tion.

2. Operate each of the brake circuits at least twiceprior to operating and moving the machine. Thesecircuits include individual activation of the servicebrake and parking brake from the operator’s cab.

a. Activate each circuit individually with the en-gine running and with hydraulic circuit fullycharged.

b. If any application or release of any brake circuitdoes not appear proper or if sluggishness isapparent on application or release, shut theengine down and notify maintenance person-nel. Do not operate machine until brake circuitin question is fully operational.

3. Check gauges, warning lights and instrumentsbefore moving the machine to insure proper sys-tem operation and proper gauge functioning. Givespecial attention to braking and steering circuitwarning lights. If warning lights come on, shutdown the engine immediately and determine thecause.

4. Cycle hoist controls and steering several times toremove trapped air. Complete steering cycles inboth directions to verify steering response,smoothness and reliability. Check seals and linesfor leaks.

5. When satisfied that all discrepancies have beencorrected, the vehicle is ready for a road test. Thistest should be done only by a capable and expe-rienced operator and should be accomplished ina large open area where plenty of maneuveringroom is available. Some of the road test itemswhich should be covered will include:

a. Repeated test of braking efficiency at progres-sively higher speeds. Start at slow speeds.Don’t take chances with higher speeds until themachine is determined to be completely safe.

b. Mechanical Drive vehicles -- Progressive upshifting and downshiftingthrough all speed ranges to insure propertransmission shifting and synchronization.

6. When all tests and checks have been made andthe vehicle is ready for work, it should be visuallyrechecked and fully serviced according to Section"P", Lubrication and Service, of the Shop Man-ual.

A few of the conditions (others may be found) whichmight be encountered after a machine has been ex-posed to the elements for a long period would include:

• Increased corrosion and fungus growth on electri-cal components in humid/tropical areas.

• Accelerated rust formation in humid climates.

• Increased sand and dust infiltration in windy, drydusty areas. (These conditions can approachsand blasting effects.)

• Deterioration of rubber products in extreme coldareas. Cables, hoses, O- rings, seals and tiresmay become weather checked and brittle.

• Animal or bird’s nests in unsealed openings.


ENGINE STORAGE-CUMMINS

Engine Storage-(Short Term)

1 Month to 6 Months

This procedure describes the proper method for the short term storage of an engine.

Prepare the Engine for Short TermStorage

1. Operate the engine at "HIGH IDLE" until thecoolant temperature is 160° F (70° C).

2. Turn the engine "OFF".

3. Disconnect the fuel lines to the engine fuel filterand the injector return line.

4. Use a preservative oil. Use Dauber T ChemicalNoxRust No. 518, or equivalent. The oil mustmeet Military Specification MIL-L-644, Type P-9.

5. Fill two containers, one with diesel fuel, and thesecond with preservative oil. Put both fuel linesin the container of diesel fuel.

6. "START" the engine.

7. After the engine is operating smoothly, transferthe fuel supply line to the container of preserv-ative oil. Operate the engine until the preservativeoil flows out of the injector return line.

8. Turn the engine "OFF". Connect the fuel lines tothe fuel filter and the injector return line.

9. Drain the oil pan sump, oil filters, and fuel filters.

10. Install the drain plugs in the oil sump. The sumpcan remain empty until the engine is ready to bereturned to service.

Put a warning tag on the engine. The tag mustindicate:

• The engine does not contain oil.

• Do not operate the engine.

11. Disconnect the electrical wiring from the fuel pumpsolenoid.

12. Turn the fuel pump manual shutoff valvecounterclockwise until it stops.

13. Crank the engine slowly. Spray lubricating oil intothe intake manifold and the inlet of the air com-pressor.

14. Cover all of the openings with tape to prevent dirtand moisture from entering the engine.

15. Drain the coolant.

NOTE: It is not necessary to drain the coolant if it is apermanent type antifreeze with a rust inhibitor.

16. Store the engine in an area that is dry and has auniform temperature.

17. Bar turn the Crankshaft two or three revolutionsevery 3 to 4 weeks.

Remove the Engine from Short TermStorage

1. Prime the lubricating system. Refer to Cummins Engine Shop Manual, (Section14-01, Engine Run-in-Period).

2. Fill the coolant system if necessary.

3. Adjust the injector and the valve clearance. Referto Cummins Engine Shop Manual, (Section 00-02, Engine Assembly).

4. Tighten the intake manifold mounting capscrewsto specified torques, refer to the Cummins Serv-ice Manual for specifications.

5. Fill the oil pan sump, oil filters, and fuel filters withrecommended lubricants and fuels..


Engine Storage- (Long Term)6 Months to 24 Months

This procedure describes the proper method for the long term storage of an engine.

Prepare the Engine for Long Term Storage

1. Operate the engine at "HIGH IDLE" until thecoolant temperature is 160° F (70° C).

2. Turn engine "OFF".

3. Drain the oil. Install the drain plugs. Use Shell66202 or equivalent, preservative oil. The oilmust meet Military Specification MIL-L-21260,Type P-10, Grade 2, SAE 30. Fill the engine tothe "HIGH" mark.

4. Disconnect the fuel lines to the engine fuel filterand the injector return line.

5. Use Daubert Chemical NoxRust No. 518, or anequivalent preservative oil. The oil must meetMilitary Specification MIL- L- 644 Type P9.

6. Fill two (2) containers:one with diesel fuel, the second with preservative oil. Put both fuel lines in the container of diesel fuel.

7. "START" engine.

8. After the engine is operating smoothly, transferthe fuel supply line to the container of preserv-ative oil. Operate the engine until the preservativeoil flows out of the injector return line.

9. Turn the engine "OFF". Connect the fuel lines tothe fuel filter and the injector return.

10. Drain the preservative oil from the engine oil pansump, the air compressor and the oil filters.

11. Remove the intake and exhaust manifolds. Spraypreservative oil into the intake and exhaust portsin the cylinder heads and in the manifolds.

12. Spray preservative oil in the intake port on the aircompressor.

13. Use a rust preventative compound that meetsMilitary Specification MIL-C-16173C, Type P-2,Grade 1 or 2. Brush or spray the compound on allof the exposed surfaces that are not painted.

14. Remove the rocker lever covers. Spray the rockerlevers, the valve stems, the springs, the valveguides, the crossheads, and the push rods withpreservative oil. Install the covers.

15. Cover all the openings with heavy paper and tapeto prevent dirt and moisture from entering theengine.

Put a WARNING tag on the engine. The tag mustindicate:• The engine has been treated with preservatives.• Do not bar turn the crankshaft.• The coolant has been removed.• The date of treatment.• Do not operate the engine.

16. Store the engine in an area that is dry and has auniform temperature.

Remove the Engine from Long Term Storage

1. Use clean diesel fuel. Flush the fuel system untilall of the preservative oil is removed.

2. Remove the plug from the main oil rifle passage.Use a hot, lightweight mineral oil. To flush all of the preservative oil from the engine:Bar the engine crankshaft three to four revolu-tions during the flushing procedure.

3. Fill the oil pan sump, oil filters, and fuel filters.

4. Drain the rust preventative compound from thecooling system. Fill the cooling system with cool-ant.

5. Prime the lubricating system. Refer to Cummins Engine Shop Manual, (Section14-01, Engine Run-in-Period).

6. Adjust the injector and the valve clearance. Refer to Cummins Engine Shop Manual, (Section00-02, Engine Assembly).

7. Tighten the intake manifold mounting capscrews.


ENGINE STORAGE - DETROIT DIESEL

Preparing Engine For StorageWhen an engine is to be stored or removed fromoperation for a period of time, special precautionsshould be taken to protect the interior and exterior ofthe engine and other parts from rust accumulation andcorrosion. The parts requiring attention and the recom-mended preparations are given below.

It will be necessary to remove all rust or corrosioncompletely from any exposed part before applying arust preventative compound.

Therefore, it is recommended that the engine be proc-essed for storage as soon as possible after removalfrom operation.

The engine should be stored in a building which is dryand can be heated during the winter months. Moistureabsorbing chemicals are available commercially foruse when excessive damage prevail in the storagearea.

Temporary Storage (30 Days Or Less)To protect an engine for a temporary period of time,proceed as follows:

1. Drain the engine crankcase.

2. Fill the crankcase to proper level with the recom-mended viscosity and grade of oil.

3. Fill the fuel tank with the recommended grade offuel oil. Operate the engine for two minutes at1,200 rpm and no load. Shut down engine, do notdrain the fuel system or the crankcase after thisrun.

4. Check the air cleaner and service it, if necessary,as outlined in Detroit Diesel Service Manual.

5. If freezing weather is expected during the storageperiod, add an ethylene glycol base antifreezesolution in accordance with the manufacturer’srecommendations.

6. Clean the entire exterior of the engine (except theelectrical system) with fuel oil and dry it withcompressed air.

To prevent possible personal injury, wear ade-quate eye protection and do not exceed 40 psi (276kPa) compressed air pressure.

7. Seal all of the engine openings. The material usedfor this purpose must be waterproof, vaporproofand possess sufficient physical strength to resistpuncture and damage from the expansion of en-trapped air.

An engine prepared in this manner can be returned toservice in a short period of time by removing the sealsat the engine openings, checking the engine coolant,fuel oil, lubricating oil, transmission oil and priming theraw water pump (if used).

Extended Storage (more Than 30 Days)To prepare an engine for extended storage, (more than30 days), follow this procedure:

1. Drain the cooling system and flush with clean, softwater. Refill with clean, soft water and add a rustinhibitor to the cooling system (refer to CorrosionInhibitor under Coolant Specifications in DetroitDiesel Service Manual .

2. Remove, check and recondition the injectors, ifnecessary, to make sure they will be ready tooperate when the engine is restored to service.

3. Reinstall the injectors, time them and adjust theexhaust valve clearance.


4. Circulate the coolant by operating the engine untilnormal operating temperature is reached 160° -185° F ( 71° - 85° C).

5. Stop the engine.

6. Drain the engine crankcase, then reinstall andtighten the drain plug. Install new lubricating oilfilter elements and gaskets.

7. Fill the crankcase to the proper level with a30-weight preservative lubricating oil MIL-L-21260C, Grade 2.

8. Drain the fuel tank. Refill with enough clean No. 1diesel fuel or pure kerosene to permit the engineto operate for about ten (10) minutes. If it isn’tconvenient to drain the fuel tank use a separateportable supply of the recommended fuel.

If engines in vehicle are stored where condensa-tion of water in the fuel tank may be a problem, addpure, waterless isopropyl alcohol (isopropanol) tothe fuel at a ratio of one pint to 125 gallons(473 L)of fuel, or 0.010% by volume. Where biologicalcontamination of fuel may be a problem, add abiocide such as Biobor JF, or equivalent to thefuel. When using a biocide, follow the manufac-turer’s concentration recommendations, and ob-serve all cautions and warnings.

9. Drain and disassemble the fuel filter and strainer.Discard the used elements and gaskets. Fill thecavity between the element and shell with No. 1diesel fuel or pure kerosene, and reinstall on theengine. If spin-on fuel filters and strainers areused, discard the used cartridges, fill the newones with No. 1 diesel fuel or pure kerosene, andreinstall on the engine.

10. Operate the engine for five (5) minutes to circulatethe clean fuel oil throughout the fuel system.

11. Refer to Detroit Diesel Service Manual and serv-ice the air cleaner.

12. Turbocharger bearings are pressure lubricatedthrough the external oil line leading from the en-gine cylinder block while the engine is operating.However, the turbocharger air inlet and turbineoutlet connections should be sealed off with mois-ture resistant tape.

13. Apply a rust preventive compound to all exposednon-painted surfaces.

14. Drain the engine cooling system.

15. Drain the preservative oil from the engine crank-case. Reinstall and tighten the drain plug.

16. Remove and clean the batteries and battery cableswith baking soda-water solution and rinse themwith fresh water. Do not allow the soda solution toenter the battery. Add distilled water to the elec-trolyte, if necessary, and fully charge the battery.Store the battery in a cool (never below 32° F or0° C) dry place. Keep the battery fully charged andcheck the level and the specific gravity of theelectrolyte regularly. Never set batteries on con-crete floor. Place on wooded blocks.

17. Insert heavy paper strips between the pulleys andbelts to prevent sticking.

18. Seal all engine openings, including the exhaustoutlet, with moisture resistant tape. Use card-board, plywood or metal covers where practical.

19. Clean and dry the exterior painted surfaces of theengine and spray with a suitable liquid automotivebody wax, a synthetic resin varnish or a rustpreventive compound.

20. Protect the engine with a good weather-resistanttarpaulin and store it under cover, preferably in adry building with temperatures above freezing.

Detroit Diesel Corporation does not recommend theoutdoor storage of engines. However, in some casesoutdoor storage may be unavoidable. If units must bekept out-off-doors, follow the preparation and storageinstructions already given. Protect units with quality,weather-resistant tarpaulins (or other suitable covers)arranged to provide air circulation.

Do not use plastic sheeting for outdoor storage.Plastic may be used for indoor storage. However,when used outdoors, moisture can condense onthe inside of the plastic and cause ferrous metalsurfaces to rust and/or pit aluminum surfaces. If aunit is stored outside for any extended period oftime, severe corrosion damage can result.

The stored engine should be inspected periodically. Ifthere are any indication of rust or corrosion, correctivesteps must be taken to prevent damage to the engineparts. Perform a complete inspection at the end of oneyear and apply additional treatment, as required.


PROCEDURE FOR RESTORING AN ENGINE TO SERVICE WHICH HAS BEEN IN EXTENDED STORAGE

1. Remove the covers and tape from all of theopenings of the engine, fuel tank and electricalequipment. Do not overlook the exhaust outlet orthe intake system.

2. Wash the exterior of the engine with fuel oil toremove the rust preventive.

3. Remove the rust preventive from the flywheel.

4. Remove the paper strips from between the pulleysand the belts.

5. Remove the drain plug and drain the preservativeoil from the crankcase. Reinstall the drain plug.Then, refer to Lubrication System in Detroit DieselService Manual and fill the crankcase to properlevel, using a pressure prelubricator, with therecommended grade of lubricating oil.

6. Fill the fuel tank with the fuel specified under FuelOil in Detroit Diesel Service Manual.

7. Close all of the drain cocks and fill the enginecooling system with clean soft water and a rustinhibitor. If the engine is to be exposed to freezingtemperatures, fill the cooling system with an eth-ylene glycol base antifreeze solution refer toCoolant Specifications in Detroit Diesel ServiceManual.

8. Install and connect the fully charged batteries.

9. Service the air cleaner as outlined in Detroit DieselService Manual.

10. Remove the covers from the turbocharger air inletand turbine outlet connections. Refer to the lubri-cating procedure outlined in Preparation for Start-ing Engine First Time in Detroit Diesel ServiceManual.

11. After all of the preparations have been completed,start the engine. The small amount of rust preven-tive compound which remains in the fuel systemwill cause a smoky exhaust for a few minutes.

NOTE: Before subjecting the engine to a load or highspeed, it is advisable to check the engine tune-up.


ELECTRIC DRIVE TRUCKS

Storage Instructions and Procedures

This instruction provides the recommended proce-dures for protecting equipment from damage duringboth short-term and long-term storage periods and formaintaining adequate protection while in storage. Alsoincluded are instructions for placing this equipmentinto service after having been stored.

For the purposes of this instruction, a short-term stor-age period is considered to be less than three months;a long-term storage period is considered to be threemonths or longer.

General Electric recommends a maximum storageperiod of three years, with these storage proceduresbeing repeated after each year. After a storage periodof three years or more, the Motorized Wheels shouldbe removed and sent to an overhaul facility for tear-down and inspection of seals and bearings. Theseshould be replaced if necessary.

Periodic (every three months) inspections should bemade to determine the lasting qualities of long-termstorage protection measures. Such inspections willindicate the need for renewing protective measureswhen necessary to prevent equipment deterioration.

Proper storage of this equipment is vital to equipmentlife. Bearings, gears, and insulation may deteriorateunless adequate protective measures are taken toprotect against the elements. For example, bearingsand gears in the Motorized Wheel gear case aresusceptible to the formation of rust; insulation in rotat-ing electrical equipment can accumulate moisture; andbearings may become pitted.

NEVER APPLY ANY SPRAY, COATING OR OTHERPROTECTIVE MATERIALS TO AREAS NOT SPE-CIFICALLY RECOMMENDED .

It is also important to note that these instructionscannot possibly anticipate every type of storage con-dition and, therefore, cannot prevent all equipmentdeterioration problems caused by inadequate storage.However, these instructions should be considered asa minimum procedure to achieve the best possibleequipment life and the lowest operating cost when theequipment is returned to service.

NOTE: Local conditions and/or experience may re-quire ADDITIONAL procedures and/or additional stor-age precautions.

Placing Equipment Into Storage

Perform the following instructions when preparingGeneral Electric equipment for storage. There arethree main equipment categories to consider:

1. When storing a truck that is operational.

2. When storing a truck that is not operational.

3. When storing major components (MotorizedWheel, alternator, etc.).

These three major categories are the basis for deter-mining required protective measures.

NOTE: In addition to these instructions, refer to truckstorage instructions.

When Storing A Truck That IsOperational

When a fully operational truck is being placed intostorage for less than three months, the best protectivemeasure which can be taken is to drive the truck oncea week for at least 30 minutes. Prior to driving the truck,the rotating equipment should be Meggered and:

1. If greater than 2 megohms, run normally.

2. If less than 2 megohms, isolate condition andcorrect before running.

Driving the truck circulates oil in the gear case to keepgears and bearings lubricated and free from rust. Italso prevents deterioration of the brushes, commuta-tors and slip rings.

When a fully operational truck is being placed intostorage for three months or longer, and the truckcannot be operated weekly throughout the storageperiod as indicated above, perform the following in-structions:

1. Drain the oil from the gear case and install rustpreventive compound 4161 (product of VanStraaten Chemical Co.)or equivalent. Fill perGeneral Electric Motorized Wheel Service Man-ual.

2. Megger the wheels as indicated in the instructionsabove. Operate the truck for at least 30 minutesto insure that the rust preventive compound hasbeen thoroughly circulated throughout the gearcase. Stop the truck and drain the rust preventivecompound.

NOTE: Do not run a LOADED truck with rust preven-tive compound in Motorized Wheel gear cases.


Do not operate trucks without oil in the MotorizedWheel gear cases.

3. Perform a megohmmeter test. Refer to the truck’sVehicle Test instructions for the correct proce-dure. Record the Megger readings for future ref-erence. They will be helpful in determining ifdeterioration is being experienced when addi-tional Megger tests are made as part of the peri-odic inspection.

4. Lift all brushes in the Motorized Wheels, blowersand the alternator. They must be removed fromthe brushholder. Disconnecting brush pigtails isnot required.

5. Cover any open ductwork with screening materialto prevent rodents from entering. Then tape overthe screen to prevent the entry of water and dirt(allow breathing).

6. Examine all exposed machined surfaces for rustor other dirt accumulation. Remove all dirt asnecessary. Remove rust by using a fine abrasivepaper. Old flushing compound can be removedwith mineral spirits (GE-D5B8). Methanol shouldbe used to remove all residue. When clean, coatwith Tarp B rust preventive. Refer to General Electric Motorized Wheel Serv-ice Manual for specifications.

7. Loosen exciter drive belts (where applicable).

8. Open all switches in the control compartment.

9. Install a 500 watt heat source inside all controlgroups which house electronic control equip-ment. These heat sources are to be energizedbelow 32° F (0° C) and de-energized above 41°F (5° C).

10. Install a 500 watt heat source inside the commu-tator chamber of both Motorized Wheels and in-side the alternator slip ring chamber. This willminimize the accumulation of moisture. A hole inthe bottom of the hubcap will accommodate theelectrical cord for the heat source in the MotorizedWheels. These heat sources are to be energizedcontinuously.

11. Seal compartment doors with a weatherproof tapeto prevent entry of rain, snow and dirt (allowbreathing).

When Storing A Truck That Is NotOperational

When a truck which is not fully operational is beingstored for a period of any length, perform the following:

1. Drain the oil from the gear case and install rustpreventive compound 4161 (or equivalent). Fillper General Electric Motorized Wheel ServiceManual.

2. Jack each side of the truck (one side at a time)enough to rotate the tires.

3. Connect a D-C welder as described in the VehicleTest Instructions (Wheel Motor inst. 400A, arm &field in stress 900- 1000 rpm arm).

4. Rotate each Motorized Wheel (one at a time) forat least 30 minutes to insure that the rust preven-tive compound has been thoroughly circulatedthroughout the gear case. Disconnect the welder.Remove the jacks. Drain the gear case.

5. If the truck is partially dismantled, pay carefulattention to ductwork, blower shrouds, etc., whichmay be exposed to weather conditions as a con-sequence. These areas will require the samesealing measures as in Step 5 above which dealswith protecting ductwork. Cover exposed blowerhousings to prevent entry of water and dirt.

6. Perform Steps 3 through 11 under When Storinga Truck that is Operational.

When Storing A Major Component

When storing a Motorized Wheel, alternator, blower orcontrol group for a period of any length, always storeit inside a warm, climate-controlled environment. Donot attempt to store individual components where theywould be exposed to inclement weather, climaticchanges, high humidity and/or temperature extremes.


Periodic Inspections

It is important that periodic inspections (every threemonths) of stored equipment be performed to insurethe continued serviceability of all protective measuresinitially taken when the storage period began. Itemswhich should be checked at each inspection intervalare listed as follows:

1. Remove the weatherproof tape from the compart-ment doors and preform a Megger test as de-scribed in the Vehicle Test Instructions. Recordthe test results and compare them with the re-corded Megger readings taken when storage firstbegan, and those taken throughout the storageperiod. Remove all test equipment and close upthe compartment. Reseal the compartment doorswith new weatherproof tape. If Megger readingsindicate a deterioration of insulation quality, tobelow 2.0 megohms then consideration should begiven to providing more protection.

2. Check all other weatherproofing tape. Replaceany that has become loose or is missing com-pletely.

3. Check all heat sources. Replace or repair anyunits which have become inoperative.

4. Check all machine surfaces which were coatedwith flushing compound when storage began. Ifcompound appears to be deteriorating, it must becleaned off and renewed.

Placing Equipment Into Service AfterStorage

When taking equipment out of storage, perform thefollowing procedures:

When A Truck Is Operational

If a truck has been operated weekly throughout thestorage period, perform a complete visual inspectionof the Motorized Wheels, blowers, alternator and con-trol compartments. Repair any defects found, thenplace the truck directly into service.

When A Truck Is Not Operational

If the truck was not operated weekly throughout thestorage period, perform the following procedures:

1. Remove all weatherproofing tape from controlcompartment doors and ductworks.

2. Remove all screening material from ductwork.

3. Remove all heat sources from Motorized Wheels,control compartments and the alternator.

4. Fill with recommended oil. Refer to the MotorizedWheel Service Manual for the type and amountoil to be used. This oil should be drained and newoil should be added after 500 hours of operation.

5. Clean all Motorized Wheel grease fittings in theaxle box. Insure that all grease lines are com-pletely full of grease. Then add the recommendedamount of grease to all fittings.

6. Install brushes in the Motorized Wheels, blowersand the alternator. Make sure that brushes movefreely in their carbonways and that they haveenough length to serve until the truck’s next in-spection period. Install new brushes if necessary.Insure that all brush pigtail screws are tight.

7. Perform a megohmmeter test. Refer to the truck’sVehicle Test Instructions for the correct proce-dure. If Megger readings are less than 2.0 me-gohms, the problem could be an accumulation ofmoisture in motor or alternator. If this is the case,the faulty component will have to be isolated anddried out using procedures recommended in theG.E.Service Manual.

8. Perform a thorough inspection of the MotorizedWheels, alternator, blowers and control compart-ments. Look for:

a. Rust or dirt accumulation on machine surfaces

b. Damaged insulation

c. An accumulation of moisture or debris

d. Loose wiring and cables

e. Any rust on electrical connectors in the controlcompartment

f. Any loose cards in the card panels

g. Any accumulation of moisture or debris inductwork.

Clean and make repairs as necessary.

9. Check retarding grids and insulators for looseconnections and dirt accumulation. Clean andmake corrections as necessary.

10. Where applicable, check exciter drive belts forcracks, and deterioration. If acceptable, set belttension to specification.

11. Before starting engine, turn on control power.Check that contactors and relays pick up and dropout normally.

12. Perform a start-up procedure on the completesystem to insure maximum performance duringservice. Refer to the truck’s Vehicle Test Instruc-tions for the complete test procedure.


For The First Hour

After all storage protection has been removed, thetruck has been cleaned and inspected and repairsmade as necessary, the Motorized Wheel gear casehas been filled with new oil, the dirt seals have beencompletely purged with new grease and the systemcompletely checked, the truck can be placed intoservice. It is recommended, however, that the truck bedriven unloaded at a low speed (10 mph) for the firsthour of operation.


PRESERVATION AND STORAGE ALLISON TRANSMISSION

Storage, New Transmission

(Prior to installation). New transmissions are tested atAllison with preservative oil and drained prior to ship-ment. The residual oil remaining in the transmissionprovides adequate protection to safely store the trans-mission for up to one year (stored inside the conditionsof normal climate and with all shipping plugs installed)without further treatment.

Preservation Methods. When the transmission is to bestored or remain inactive for an extended period (oneor more years), specific preservation methods arerecommended to prevent damage due to rust, corro-sion, and organic growth in the oil. Preservation meth-ods are presented for storage with and withouttransmission fluid.

Storage, One Year -- Without Oil

1. Drain the oil.

2. Spray two ounces (60 milliliters) of VCI #10through the fill tube.

3. Seal all openings and the breather with moisture-proof tape.

4. Coat all exposed, unpainted surfaces with pre-servative grease such as petroleum (MIL-C-11796, Class 2).

5. If additional storage time is required, repeat steps(2), (3) and (4) at yearly intervals.

Storage, One Year With Oil (normally in a vehiclechassis)

1. Drain the oil and replace the oil filter element(s).

2. Fill the transmission to operating level with amixture of one part VCI #10 (or equivalent) to 30parts C-3 transmission fluid. Add 1/4 teaspoon ofBiobor JF (or equivalent) for each 3 gallons (11liters) of fluid in the system.

NOTE: When calculating the amount of Biobor JFrequired, use the total volume of the system, not justthe quantity required to fill the transmission. Includeexternal lines, filters, and the cooler.

3. Run the engine for approximately five minutes at1500 rpm with the transmission in neutral.

4. Drive the vehicle. Make sure the transmissionshifts through all ranges. Make sure the lockupclutch is working.

5. Continue running the engine at 1500 rpm with thetransmission in neutral until normal operatingtemperature is reached.

If the unit does not have a converter-out tempera-ture gage, do not stall the converter.

6. If normal operating temperature is less than 225°F (107° C), shift the transmission to the highestforward range and stall the converter.When the converter-out temperature reaches225° F (107° C), stop the engine. Do not exceed225° F (107° C).

7. As soon as the transmission is cool enough totouch, seal all openings and the breather withmoisture-proof tape.

8. Coat all exposed, unpainted surfaces with pre-servative grease such as petrolatum (MIL-C-11796, Class 2).

9. If additional storage time is required, repeat steps(2) through (8) at yearly intervals; except, it is notnecessary to drain the transmission each year.Just add Motorstor and Biobor Jf (or equivalents).

Restoring Transmission to Service

1. Remove all tape from openings and the breather.

2. Wash off all external grease with mineral spirits.

3. If the transmission is new, drain the residualpreservative oil. Refill the transmission to theproper level with C-4 transmission fluid.

4. If the transmission was prepared for storage with-out oil, drain the residual oil and replace the oilfilter elements. Refill the transmission to theproper level with C-4 transmission fluid.

5. If the transmission was prepared for storage withoil, it is not necessary to drain and refill thetransmission with new transmission fluid. Checkfor proper fluid level. Add or drain transmissionfluid as required to obtain to proper level.


NOTES


SECTION B

STRUCTURES

INDEX

STRUCTURAL COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-1COWL AND HOOD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-1DECKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-1RIGHT DECK STRUCTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-1Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B2-2

DUMP BODY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-2

BODY PIVOT PINS AND SPACERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-2Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-2Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-2

BODY-UP PIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-3Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-3

BODY PADS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-3ROCK EJECTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4

Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4BODY POSITION INDICATORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4LINER PLATES/BODY REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4BODY-UP LIMIT SWITCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4

Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B3-4

FUEL TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2

VENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2GAUGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B4-2

B01006 9/90 Index B1-1

NOTES

B1-2 Index B01006 9/90

STRUCTURAL COMPONENTS

COWL AND HOODThe grille, cowl and hood assemblies on the truck canbe removed for service to the engine, radiator or airconditioning condenser. Refer to Section C, CoolingSystem, for removal, installation and adjustment pro-cedures.

DECKSThe left and front left deck structures are removedduring cab removal and in the event repair proceduresto the structures are required. Refer to Section N, TruckCab, for removal and installation procedures for the leftand front left deck structures.

RIGHT DECK STRUCTURE

Do not work under raised body without body uppin installed.

Removal

1. Raise the truck body and install the body-up re-taining pin to secure the body in the full raisedposition.

2. Turn key switch "off", and shut down engine.

3. Identify the battery cables at the terminals on thebatteries. Refer to CAUTION, Section "D", BatteryCharging Circuit Components for removal proce-dure.

4. Remove the necessary retaining devices securingthe battery and cables to the hood and deckstructures and position cables out of the way.

5. Remove batteries and place them in an out of theway area. Place batteries on wood blocking orpallets. Storage of batteries directly on concretefloor can damage batteries.

6. Identify and disconnect the necessary connec-tions at the cold starting aid.

7. Loosen hose clamps on air inlet piping and removesections of piping as required for deck removal.Cover and seal engine air inlet to prevent entry ofcontamination.

8. Identify and tag electrical wires on the headlightsand turn signal mounted on the right deck struc-ture. Disconnect electrical wires.

9. Loosen the capscrews retaining the right deck onthe truck and attach a lifting strap around struc-ture so its weight is evenly distributed. Take upslack. Remove capscrews and then move rightdeck structure to a work area.

Installation

1. Install lifting strap around right deck structure andlift structure into position on truck.

2. Install all capscrews retaining deck structure to thetruck. Tighten to standard torque.

3. Connect the electrical wires on the headlights andturn signal mounted on the right deck structure.

4. Be certain air inlet piping is completely cleaninternally. Install tubes and tighten securely to aircleaner.

Be certain tubes engage rubber elbows and humphoses properly. Position clamps so elbows andhump hoses are completely compressed on tubeswhen clamps are tightened.

5. Connect the cold starting aid connections.

6. Install batteries into battery box. Refer to CAU-TION, Section "D", Battery Charging Circuit Com-ponents. Route and connect cables to thebatteries. Connect all harness retaining devices toprevent abrasion and/or damage. Install batteryretaining devices.

7. Start engine and remove body-up retaining pin.Lower body.

B02007 Structural Components B2-1

Inspection

The decks of the truck are covered with anti-slip sur-faces. These anti-slip coverings should be kept cleanand replaced as they become worn.

The anti-slip material on the decks should be in-spected and maintained for the safety of all person-nel. Particular attention should also be directed tothe condition of the stair and handrail structures.Loose or missing mounting hardware, cracked orbent areas, etc., should be repaired or replacedimmediately.

B2-2 Structural Components B02007

DUMP BODYRemoval

1. Park truck on hard level surface and block allwheels. Connect cables and lifting device to thedump body and take up slack as illustrated inFigure 3-1.

Before raising or lifting body be sure there is ade-quate clearance between body and overheadstructures or electric power lines.

Be sure that lifting device is rated for at least a 11ton (9,988 kg) capacity. Allow for added linerplates and haulage remaining in body.

2. Remove mud flaps and rock ejectors from bothsides of the truck.

3. Loosen three capscrews holding exhaust box tomounting bracket. Tilt exhaust box away frompivot exhaust seal.

4. Remove pivot exhaust seal.

5. On each side of the dump body, remove thecapscrew and lockwasher (3, Figure 3-2) from thepin (2) on top hoist cylinder eye.

Some means of supporting hoist cylinders will benecessary prior to removing hoist cylinder pin.

6. Remove the top hoist cylinder pin (2) from thedump body bracket.

7. Remove the capscrews, washers and nuts (4,Figure 3-3) securing the pivot pin to dump bodypivot point. Remove the pivot pin (3) from eachpivot point. Pivot pin spacers (1) will come outafter pin is removed.

8. Lift dump body clear of truck and move to storageor work area. Place on blocks.

9. Inspect bushings (2) in the body pivots for wear ordamage. Replace, if necessary.

FIGURE 3-1. DUMP BODY REMOVAL

1. Lifting Cables 2. Guide Rope

FIGURE 3-2. HOIST CYLINDER MOUNTING

1. Dump Body 4. Hoist Cylinder2. Pin 5. Bearing3. Capscrew and 6. Retainer Rings Lockwasher

B03007 10/90 Dump Body B3-1

Installation

1. Attach lifting device to dump body and lower overthe truck frame. Align the dump body pivot withframe pivots.

2. Install body pivot pin (3, Figure 3-3) on each sideof truck. Install spacers (1) removed during bodyremoval: Note location of spacers (1, Figure 3-3).

3. Secure pivot pin in place with capscrews, washersand nuts (4). Tighten capscrews to standardtorque.

4. Install pivot exhaust seal between body pivotstructure and exhaust box. Contact surfaces mustbe clean and smooth at pivot of exhaust box andbody pivot structure. Tighten capscrews holdingexhaust box to mounting bracket to standardtorque. Check for exhaust leaks when startingengine.

5. Align top eye of hoist cylinder and install hoistcylinder pin (2, Figure 3-2). Secure pin with cap-screws. Tighten capscrews to standard torque.

6. Install mud flaps and rock ejectors on dump body.

BODY PIVOT PINS AND SPACERSThe HAULPAK dump body is centered on the truckframe by use of spacers (1, Figure 3-3) located in thepivot pin assemblies.

Removal

1. Support the weight of the dump body (approxi-mately 12 tons) by use of an overhead crane orblocking to relieve pressure on the pivot pins.

2. Remove capscrew, washer and nut (4) from pivotpin assembly.

3. Remove pivot pin (3) from structure.

4. Inspect spacers (1) and replace with new spacersif wear or damage is indicated.

5. Inspect bushing (2) for wear or damage. Replaceif necessary.

6. Inspect pivot pin (3) and grease channels. Re-place if worn or damaged.

Installation

1. Pivot pin spacers (1, Figure 3-3) must be installedto provide an equal gap on either side of the bodyguide (1, Figure 3-4). If dimensions indicated arenot obtained, spacers,bushings, and/or pivot pinsmay be worn and must be replaced.

2. Install pivot pin (3, Figure 3-3) through frame,spacer, bushing and spacer, as shown.

3. Align pivot pin hole with mounting bracket hole.Install capscrew, washer and locknut. Tightencapscrew to standard torque.

4. Install lube fitting, if removed, and fill lube passagewith recommended grease.

FIGURE 3-3. BODY PIVOT PIN CROSS SECTION

1. Spacers 3. Pivot Pin 2. Bushing 4. Capscrew, Washer and

Nut

FIGURE 3-4. BODY GUIDE ADJUSTMENT1. Body Guide 2. Body

B3-2 Dump Body B03007 10/90

BODY-UP PINThe body up pin is intended to be used as a safety pinto hold the body in the up position while the technicianworks under the body.

Body-Up Pin Installation

Always store pins in body storage holes. Place-ment of the pins in mainframe or matching body-upholes located on the body can cause damage toframe or body during dumping cycle.

1. Before raising body, remove cotter pins frombody-up pin and remove from storage holders.

2. Raise body of truck.

3. Align holes in body with holes in main frame. Insertsafety pins into holes. Refer to Figure 3-5.

4. Insert cotter pin back into pin hole.

5. After servicing has been completed, remove body-up pins and return to proper storage holder.

BODY PADNOTE: It is not necessary to remove the dump body forreplacing the body pads. Replace pads if worn exces-sively or damaged.

1. Raise dump body to sufficient height for removalof body pads.

Place blocks between dump body and frame. Se-cure blocks in place.

2. Remove capscrews, lockwashers and rubberbody pad from body pad mounting. Refer to Fig-ure 3-6.

3. Install new rubber body pads and secure withcapscrews and lockwashers. Tighten nuts tostandard torque.

NOTE: If body pad mounting brackets have been dam-aged, new mounting brackets should be positionedso body pads are parallel to frame rail. Body padsshould have full and even contact of pads to frame rail.

FIGURE 3-6. BODY PAD1. Body Pad 2. Dump Body

FIGURE 3-5. BODY-UP PIN INSTALLATION

1. Body Up Retaining Pin 3. Body Pivot Pin2. Body 4. Main Frame

B03007 10/90 Dump Body B3-3

ROCK EJECTORSRock ejectors are placed between the rear dual wheelsto keep rocks or other material from lodging betweenthe dual tires. Failure to keep ejectors in working ordercould allow debris to build up between the dual wheelsand cause damage to the tires.

Inspection

1. The ejectors (1, Figure 3-7) must be positioned onthe center line between the dual wheels within0.25 in. (6.35 mm).

2. Arm structure must be straight.

3. The arm structure should be approximately 2.00in. (5.10 cm.) away from the wheel spacer ring.

4. Check for wear on mounting brackets and clevispins.

If any of these conditions are unsatisfactory, repair orreplace the item.

BODY POSITION INDICATORThe body position indicator is a structure mounted tothe canopy of the dump body. The indicator is locatedto the front right of the operators cab and is designedas a visual reference for the dump body being in thedown position.

LINER PLATES/BODY REPAIRLiner plates may be added to the original body to addresistance to wear from abrasive material. If such plateshave been added, the weight must be consideredpart of the payload and the material being hauledshould be reduced accordingly to prevent exceedingthe maximum Gross Vehicle Weight (GVW).

If repair or replacement of the liner plates or other bodyparts is required, contact the HAULPAK® Distributorfor information on type of material required.The addition of sideboards to increase payload is notrecommended without factory approval.

BODY-UP LIMIT SWITCH The Body-Up Limit Switch is designed to stop hoistcylinder extension before maximum travel (completeextension) occurs. The body-up limit switch is a mag-netic proximity switch mounted on the inboard side ofthe right frame rail near the upper rear suspensionmount. The limit switch is installed in the wiring circuitfor the hoist control.

When the indicator arm (mounted on the body pivotear) moves near the body-up limit switch, the circuit tothe hoist up solenoid is interrupted; this limits body-uptravel by preventing additional oil flow to the hoistcylinders.

Body-Up Limit Switch Adjustment

NOTE: Prior to adjusting the Body-Up Limit Switch, athorough inspection of the body pivot pins, spacers,and bushings should be made. Excessive wear of these parts may allow the body toshift during operation and cause damage to the Body-Up Limit Switch. Refer to Dump Body Pivot Pins, forinformation regarding these components.

1. Park truck on level surface, apply park brake andblock wheels. Check for sufficient overhead clear-ance to allow body to be raised. Remove IndicatorArm Plate (2, Figure 3-8) from body.

2. Start engine and operate at low idle. Place hoistcontrol switch in "Raise" position and allow bodyto be raised to maximum hoist cylinder extension.

FIGURE 3-7. ROCK EJECTOR INSTALLATION

1. Rock Ejector Arm 2. Rear Wheel Spacer Ring

B3-4 Dump Body B03007 10/90

3. Measure length of lower hoist cylinder rod shownas "A", Figure 3-8. Record measurement.

4. Lower body to frame. Subtract 4 in. (10.16 cm.)from dimension found in Step 3 and record asdimension "B".

5. Raise body until exposed length of lower hoistcylinder rod equals dimension "B".

6. Install indicator arm plate (2, Figure 3-9). Loosencapscrews and nuts (4, Figure 3-10) and adjustgap between body-up limit switch (2) and indica-tor arm plate (1) to 0.25 in. (6.35 mm.) Tighten nuts(4) to standard torque.

7. Loosen capscrews (1, Figure 3-9) on indicator armplate (2). Adjust arm to overlap end of switch (5)by 0.75 ± 0.25 in. (19.05 ± 6.35 mm). Tightencapscrews to standard torque.

8. Place hoist control switch in "Power Down" posi-tion and lower body to frame.

FIGURE 3-8. HOIST CYLINDER MEASUREMENT

A. Length of Cylinder Rod @ Complete ExtensionB. Complete Extension less 4 in. (10.16 cm).

FIGURE 3-9. BODY-UP LIMIT SWITCH ADJUSTMENT

1. Tapped Pads and Capscrews 4. Mounting Bracket with Mounting Hardware2. Indicator Arm Plate 5. Body-Up Limit Switch with Mounting Hardware3. R.H. Frame (Inboard Rear)

B03007 10/90 Dump Body B3-5

9. Place hoist control switch in "Raise" position andoperate engine at approximately 1200 RPM. Observe body as it raises, when indicator arm (5)passes by body-up limit switch the hoist valveshould shift and stop flow of hydraulic oil to hoistcylinders, preventing hoist cylinders from fullyextending.

10. If cylinders continue to go to full extension, adjust-ment procedures of body-up limit switch must berepeated until full cylinder extension is prevented.

Maintenance

1. Before each operating shift remove any accumu-lated debris from indicator arm and body-upswitch (1 and 2, Figure 3-10).

2. Inspect for any damage to indicator arm, body-up,switch, and electrical connections.

NOTE: If capscrews are found to be loose or replace-ment of components is necessary, an adjustment ofbody-up switch will be required.

3. Inspect body pivot pins, spacers, and bushings forwear. Refer to "Dump Body Pivot Pins".

FIGURE 3-10. INDICATOR ARM ADJUSTMENT

1. Indicator Arm Plate 3. Mounting Bracket2. Body-Up Limit Switch 4. Capscrews and Nuts

B3-6 Dump Body B03007 10/90

FUEL TANKRemoval

1. Drain all fuel from tank to reduce the weight to behandled. Disconnect all fuel and hydraulic hosesand cap to prevent contamination.

The empty fuel tank weighs approximately 622 lbs.(282 Kg.). Be sure lifting device is capable of liftingthe load.

2. Loosen the bottom mount capscrew (9, Figure 4-1)and top U-bolts, nuts and washers (3) and take upslack of hoist or fork lift. Remove capscrews andmove tank to safe working area.

NOTE:Hoist valve weights approximately 40 lbs.(18.2 Kg).

3. Remove hoist valve, fuel gauge (5) and vent (2)from tank, and other fittings as required to carryout interior cleaning or repair.

FIGURE 4-1. FUEL TANK INSTALLATION

1. Fuel Cap2. Vent3. U-Bolts, Nuts and Washers

4. Lifting Eye5. Fuel Gauge6. Fuel Tank

7. Drain Petcock8. Cover9. Rubber Mount, Capscrew,

and Nut

B04003 3/92 Fuel Tank B4-1

Installation

1. Thoroughly clean the frame mounting brackets.Inspect the lower rubber mount for wear or dam-age and replace if necessary.

2. Install hoist valve to fuel tank using three cap-screws and washers. Tighten capscrews to 65ft. ils. (88 N.m.) torque.

3. Lift the fuel tank into position being carefull not todamage the hoist valve. Install the rubber mount,capscrew and lockwashers (9), but do not tighten.

4. Install the U-bolts, washers and nuts (3). Tightennuts to 125 ft.lbs. (170 N.m) torque.

5. Tighten lower mount capscwew to 200 ft.lbs. (271N.m) torque.

6. Connect hoses removed during removal proce-dure.

If a tank is to be weld repaired, special precautionsare necessary to prevent fire or explosion. Consultlocal authorities if necessary, on safety regulationsbefore proceeding.

Cleaning

The fuel tank is provided with a drain (7, figure 4-1) anda cleaning port (8) in the side that allows steam orsolvent to be utilized in cleaning tanks that have accu-mulated foreign material.

It is not necessary to remove the tank from the truckfor cleaning of sediment, however rust and scale on thewalls and baffles may require complete tank removal.This allows cleaning solutions to be in contact with allinterior surfaces by rotating the tank in various posi-tions, etc.

Prior to a cleaning procedure of this type, all vents, fuelgauges, and hose connections should be removed andtemporarily sealed. After all scale, rust, and foreignmaterial has been removed, the temporary plugs canbe removed.

If a tank has been damaged and requires structuralrepair, carry out such repairs before final cleaning. Asmall amount of light oil should be sprayed into the tankto prevent rust if the tank is to remain out of service. Allopenings should be sealed for rust prevention.

VENTThe fuel tank is vented through a small mesh type filter(2, Figure 4-1) installed in a port on the top of the tank.This filter should be cleaned periodically and can beblown out with solvent and reused. The area aroundthe vent must be free of caked mud and debris thatwould cover the vent and prevent proper fuel suctionand return.

Refer to Section ‘‘M’’ for information on various quickfill systems.

GAUGEA direct readout type gauge (5, Figure 4-1) is mountedin an opening in the side of the tank. The gauge is amagnetic arm type with a float inside the tank.

Removal

1. Drain fuel below level of gauge.

2. Loosen the small screws holding the dial face inthe fuel gauge sender unit and remove.

3. Loosen four socket head screws in sender unit andremove from tank.

Installation

1. Install new gasket.

2. Reinstall the sender unit in tank. Take care toinsure that float is oriented properly and worksfreely in vertical plane during installation.

3. Reinstall four socket head capscrews and tightento standard torque.

4. Reinstall dial face in sender. If a remote readout inthe cab is utilized, reconnect wire(s).

5. Refill tank and check for leaks.

B4-2 Fuel Tank B04003 3/92

SECTION CENGINE, FUEL, COOLING AND AIR CLEANER

INDEX

COOLING SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-1RADIATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-3Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-4

HEAT EXCHANGER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-4Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-4Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-5Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C3-5

ENGINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4-3Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C4-5

AIR FILTRATION SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-1AIR CLEANER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-1

Service Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-1Filter Element Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-1

MAIN FILTER ELEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-1Main Filter Element Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-3Precleaner Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-4Cleaning Precleaner Tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-4Air Intake Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C5-5

ENGINE COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-1THROTTLE CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-1THROTTLE CONTROL PEDAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-1

Removal/Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-1THROTTLE CONTROL LEVER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-1

Throttle Control Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-3ATEC THROTTLE POSITION SENSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-4

Throttle Position Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-4Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-4Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-5

FAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-5Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-5Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-5

FAN BELT ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-5ALTERNATOR BELT ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C6-6

C01006 8/94 Index C1-1

NOTES

C1-2 Index C01006 8/94

COOLING SYSTEM

RADIATORBoth sides of the radiator are mounted with rubbermounts to the radiator support structures. On top ofthe radiator is an adjustable rod, rubber mounted to thecowl, to position radiator core parallel to engine fan.The bottom radiator tank is also used as the transmis-sion oil cooler. A separate heat exchanger for the rearoil-cooled disc brakes is mounted below the radiatorbottom tank.

Radiator Removal

If necessary to remove engine, raise body and installbody-up retaining pin (1, Figure 3-1) to secure body infull raised position.

1. Disconnect cables from battery terminals. Removecable from negative terminal first. Refer to Section"D", Electrical System "Battery Equalizer".

2. Remove capscrews and retainer (5, Figure 3-2).Remove grille (6).

3. Disconnect horn wires, remove horn.

Serious personal injury may result if hoses at con-denser are disconnected prior to properly dis-charging the air conditioning system. Refer toSection "M" for proper discharging procedure.

4. If radiator is being removed only for repair of theradiator, remove condenser mounting bracketcapscrews (4, Figure 3-2). Secure condenser as-sembly to allow enough room for radiator re-moval.

5. If radiator is being removed to permit engineremoval, refer to Section "M" for procedures todischarge the air conditioning system. Discon-nect hoses at condenser, tightly cap hoses andfittings to prevent moisture entry, and removecondenser assembly (3, Figure 3-2).

6. If coolant is to be reused, provide a clean containerto hold approximately 48 gal. (182 l) of coolant.



FIGURE 3-2. RADIATOR REMOVAL

1. Cowl 5. Capscrews 2. Capscrews 6. Grille3. Condenser 7. Radiator4. Capscrews

C03011 Cooling System C3-1

Before removing any cooling system components,release cooling system pressure by turning radia-tor cap counterclockwise to the first notch. Failureto release pressure may result in hot coolant beingexpelled causing serious injury.

7. Remove radiator cap. To drain radiator, open draincock on bottom of large coolant tube to bottomtank on right side of radiator.

8. Remove adjustment rod nut (2, Figure 3-3) on toptank.

9. Remove capscrews (1, Figure 3-4) and hood struc-tures (2).

10. Remove capscrews (2, Figure 3-2) and cowl (1).

11. Disconnect wire from low coolant level probe in toptank.

12. Disconnect and cap all hoses from top and bottomtank of radiator.

13. Disconnect and cap hoses from transmission atbottom tank.

14. Remove fan guard (7, Figure 3-3) from radiatorshroud (6).

Heat exchanger weighs approximately 280 lbs (127kg). Use adequate lifting device.

15. Remove capscrews attaching lower coolant tubeto support bracket.

16. Support heat exchanger. Remove four capscrewsand lower heat exchanger onto supports and se-cure safely.

17. Attach lifting device to tapped blocks on radiatortop tank and take up slack.

18. Remove radiator mount capscrews securing radia-tor to support structures (1, Figure 3-5). Maneuverradiator away from fan, taking care not to damagefan or radiator.

19. Set radiator aside for repair, if required.

20. Inspect hoses and clamps, rubber mounts at radia-tor supports, adjustment rod, and condenserbracket. Replace as necessary.


1. Adjustment Rod 6. Radiator Shroud2. Adjustment Rod Nut 7. Fan Guard3. Top Radiator Tank 8. O-Ring4. Lower Radiator Tank 9. Coolant Flange (Transmission Cooler) (To Engine Block)5. Heat Exchanger (Rear Oil-Cooled Disc Brakes)

FIGURE 3-4. HOOD REMOVAL

1. Capscrews 2. Hood Structure

C3-2 Cooling System C03011

Radiator Installation

1. Place radiator rubber mount (2, Figure 3-5) in eachradiator support structure (1).

2. Raise radiator into position, taking care not todamage fan or radiator.

3. Install capscrew (3), washer (4) and nut (5).Tighten to standard torque.

4. Install adjustment rod (1, Figure 3-6) washers,rubber mount and nuts to cowl.

5. Raise cowl into position, install adjustment rod (1,Figure 3-6) into bracket on top tank (3).

6. Install cowl mounting capscrews (2, Figure 3-2)and tighten to standard torque.

7. Adjust rod, if necessary, so radiator core is parallelto fan. Tighten nuts to standard torque.

8. Install fan guard (7, Figure 3-6). Tighten capscrewsto 25 ft.lbs. (35 N.m) torque.

9. Remove caps and connect all hoses to top andbottom tanks to engine. Tighten clamps securelyto prevent leaks.

10. Install new O-rings and connect transmissioncooler lines. Tighten split flange capscrews tostandard torque.

11. Install new O-ring (8, Figure 3-6) on radiator mount-ing surface (use a non-petroleum base lubricant).Install heat exchanger and capscrews. Tighten to90 ft.lbs. (122 N.m) torque.

12. Connect coolant line to heat exchanger, tightenclamps securely to prevent leaks.

13. Install capscrews into lower coolant tube supportbracket. Tighten to standard torque.

14. Connect wire to low coolant probe.

15. Install hood structures and capscrews (Figure 3-4).

16. Position air conditioner condenser (1, Figure 3-7)and mount bracket to support structures. Installrubber mounts, capscrews, washers and nuts.Tighten to standard torque.

17. Connect air conditioner hoses to condenser, ifremoved. Refer to Section"M" for evacuation andcharging procedures.

FIGURE 3-7. CONDENSER INSTALLATION

1. Condenser 3.Rubber Mount2. Mount Bracket


1. Adjustment Rod 6. Radiator Shroud2. Adjustment Rod Nut 7. Fan Guard3. Top Radiator Tank 8. O-Ring4. Lower Radiator Tank 9. Coolant Flange (Transmission Cooler) (To Engine Block)5. Heat Exchanger (Rear Oil-Cooled Disc Brakes)

FIGURE 3-5. RADIATOR MOUNTING

1. Radiator Support 4. Washer2. Rubber Mount 5. Nut3. Capscrew


18. Install horn and connect wires. Install grille.

19. Add approximately 48 gal. (182 l) of coolant. Referto Section "P", Lubrication And Service, for anti-freeze recommendations.

Radiator Repair

Radiator core repairs should be performed by a quali-fied repair facility. The core, top and bottom tanks, andgaskets are available as replacement components.Contact your HAULPAK® distributor.

The bottom tank of the radiator contains the heatexchanger for the transmission. If a leak occurs in theheat exchanger, antifreeze/coolant may contaminatethe transmission oil and/or transmission oil may con-taminate the engine cooling system.

If the engine coolant is found to be contaminated withoil, the system must be examined for leaks and cor-rected. Then the system must be flushed to remove oilcontamination, and finally, refilled with a clean coolantsolution.

If a leak has been found or suspected in the heatexchanger, the transmission oil must be examinedIMMEDIATELY. Ethylene glycol (even in smallamounts) will damage friction-faced clutch plates.Contact your HAULPAK® distributor for ethylene glycoldetection test kits.

If ethylene glycol is found in the transmission oil,the transmission should be removed, completelydiassembled, cleaned and examined, and ALL fric-tion-faced clutch plates replaced.

HEAT EXCHANGER(For Oil-Cooled Rear Disc Brakes)

The heat exchanger is mounted to the bottom tank ofthe radiator. Its main purpose is to cool the hydraulicoil used in the wet disk brake housing. The enginecoolant passes through a group of tubes located in thecenter of the heat exchanger housing. The hydraulic oilcirculates around the tubes allowing heat to dissipatefrom the hydraulic oil. The cooled hydraulic oil flows tothe steering pump and to the rear brake housings andengine coolant flows through the engine and back tothe radiator.

Removal

1. Park truck on level surface. Block wheels. Turn keyswitch "OFF" to shut down engine. Wait at least90 seconds. Rotate steering wheel back and forth;no movement should occur.

2. Open bleeder valves to bleeddown brake accumu-lators. Wait at least 90 seconds for accumulatorsto bleeddown. Close bleeddown valves.

3. If coolant is to be reused, provide a clean containerto hold approximately 48 gal. (182 l) of coolant.

Before removing any cooling system components,release cooling system pressure by turning radia-tor cap counterclockwise to the first notch. Failureto release pressure may result in hot coolant beingexpelled causing serious injury.

4. After pressure is released, remove radiator cap.Open drain cock on large coolant tube attachedto heat exchanger to drain radiator.

5. Remove two hydraulic lines connected to ex-changer. Be prepared to contain approximately 5gal. (19 l) of hydraulic oil remaining in lines.

6. Loosen two engine guard capscrews at mountingbrackets on horse collar. Do not remove cap-screws.

7. Place adequate lifting device under engine guardand remove four capscrews attaching guard tofront bumper. Engine guard weighs approxi-mately 150 lbs. (70 kg). Lower guard away fromengine.

8. Loosen hose clamps securing rubber elbow tolarge coolant tube and heat exchanger. Removetwo capscrews securing coolant tube to radiatorbracket. Remove tube and rubber elbow fromheat exchanger.

9. Support or block under heat exchanger and re-move four capscrews securing exchanger to ra-diator.

CAUTION! Heat exchanger weighs approximately280 lbs (127 kg).

10. Use an adequate lifting device to lower heat ex-changer from its location under the radiator. Re-move exchanger to a clean work area.


Installation

1. Clean all mounting surfaces and hose connec-tions. Inspect hoses and clamps. Replace if dam-aged.

2. Install new O-rings (8, Figure 3-6) into radiatorbottom tank housing. Lubricate O-ring and neckof heat exchanger with a non-petroleum type lu-bricant.

3. Lift heat exchanger up to the radiator, move intoposition, and install four capscrews. Do not twistor damage O-ring in lower tank.

4. Tighten capscrews to 90 ft. lbs. (122 N.m) torque.

5. Install both hydraulic lines with new O-rings ontoheat exchanger. Install split flange and cap-screws. Tighten to 90 ft.lbs. (122 Nm) torque.

6. Install large coolant tube and rubber elbow to heatexchanger. Install clamps. Tighten secureley toavoid leakage.

7. Install two capscrews securing coolant tube toradiator mounting bracket. Tighten to standardtorque.

8. Use an adequate lifting device, raise engine guardinto position. Install four capscrews attaching en-gine guard to front bumper. Tighten capscrews tostandard torque. Engine guard weighs approxi-mately 150 lbs. (70 kg).

9. Tighten engine guard capscrews at mountingbrackets on horse collar to standard torque.

10. Add approximately 48 gal (182 l) of coolant. Referto Section "P", Lubrication And Service, for anti-freeze recommendations.

11. Check oil level in hydraulic tank. Add oil if needed.Start engine and allow accumulators to charge tosystem pressure.

12. Allow truck to idle at 1000 RPM. Check for anyleakage at hose connections on heat exchanger,tighten fittings if leakage occurs.

13. Remove blocks from wheels.

Heat Exchanger Repair

Heat exchanger repairs should be performed by aqualified repair facility. The heat exchanger and gas-kets are available as replacement components. Contact your HAULPAK® distributor.

The heat exchanger for the rear oil-cooled disc brakesis mounted to the bottom tank of the radiator. If a leakoccurs in the heat exchanger, antifreeze/coolant maycontaminate the hydraulic oil and/or hydraulic oil maycontaminate the engine cooling system, and entirehydraulic system.

If the engine coolant is found to be contaminated withoil, the system must be examined for leaks and cor-rected. The system must then be flushed to remove oilcontamination, and finally, refilled with a clean coolantsolution.

If a leak is found or suspected in the heat exchanger,the hydraulic oil must be analyzed IMMEDIATELY.Ethylene glycol (even in small amounts) will damagefriction-faced disc plates used in the rear wet disc brakeassemblies.

If ethylene glycol is found in the hydraulic oil, thehydraulic system must be drained and flushed to re-move all contamination, and finally, refilled with cleanhydraulic oil. Both rear wet disc brake assembliesshould be removed, completely disassembled,cleaned and examined, and ALL friction-faced discplates replaced. Contact your HAULPAK® distributorfor ethylene glycol detection test kits.


NOTES


ENGINEThe 210M HAULPAK® is powered by a Cummins KTTA-19C engine. The front engine mount is attached to acradle between the frame rails. The cradle is mountedto the frame with rubber mounts. The rear enginemounts are mounted on frame brackets attached toeach side of the flywheel housing with rubber mounts.

Engine Removal

Engine weighs approximately 4300 lbs (1950 kg).Make certain all lifting apparatus is of adequatecapacity.

1. Remove radiator. Refer to instructions coveringradiator removal in this section.

NOTE: Plug all ports and cover hose connectionswhen disconnected to prevent dirt and foreign mate-rial from entering.

2. Remove air inlet piping from air cleaner to engine.

3. Remove exhaust piping from turbocharger to flexpipes.

4. Remove both halves of driveline protector. Referto Figure 4-1.

5. Remove capscrews (3) securing U-joint to flywheeladapter.

6. Make sure cross bearing caps are separated fromadapter. Support driveline so it cannot slide apartwhen engine is removed.

7. Remove transmission cooler hose clamps. Dis-connect and cap hoses from transmission.

8. Remove clamps securing hoses to front enginemount cradle. Position hoses so they will notinterfere with cradle removal.

9. Disconnect fuel lines, throttle cable and ATECthrottle potentiometer cable at fuel lever.

NOTE: Identify and mark connection points of all wires.

10. Disconnect all wiring to engine.

11. Measure distance from front engine cradle toframe mounts (Figure 4-2). Measurement shouldbe 0.94 in. (23.8 mm). If less than this dimension,rubber mount should be replaced after engine isremoved.

F IGURE 4-1. DRIVELINE REMOVAL

1. Driveline Protector, 4. Capcrews Upper Half 5. Driveline Protector, 2. Capscrews Lower Half3. U-joint Capscrews 6. Driveline

FIGURE 4-2. FRONT ENGINE CRADLE MOUNT

1. Cradle Mount 3. Large Washer2. Engine Mount Capscrews

C04008 4/90 Engine C4-1

12. Measure distance from rear engine mount, oneach side, to frame mount at all four rubbermounts (Figure 4-3). Distance should be 1.31 in.(33.3 mm). If less than this dimension, replacerubber mounts after engine is removed.

13. Place engine lifting tool* or equivalent betweencylinder heads, one on each end of engine, underprotruding cast portion (2, Figure 4-4). Take upslack.

* Refer to Section "M" Special Tools for Lifting Toolfabrication dimensions.

14. Remove capscrews securing front engine mountto cradle (2, Figure 4-2), and capscrews at eachrubber mount of cradle.

15. Remove capscrews from four rear engine rubbermounts (1, Figure 4-3).

16. Raise front of engine enough to remove frontcradle.

17. Carefully maneuver engine forward and upward toclear horse collar and front bumper.

18. Move to clean work area and position on supportsto prevent damage to oil pan, etc.FIGURE 4-3. REAR ENGINE MOUNT

1. Rubber Mount Capscrews 2. Rubber Mount

FIGURE 4-4. PLACEMENT OF ENGINE LIFTING TOOL

1. Heads 2. Lift Point

C4-2 Engine C04008 4/90

Engine Installation

1. If removed, position flexible coupling (1, Figure4-5) on flywheel. Install capscrews (3), tighten tostandard torque and safety wire capscrew heads.

2. If removed, install adapter (2) on flexible coupling(1). Install capscrews (4) and tighten to 70 ft. lbs.(95 N.m) torque. Safety wire capscrew heads.Install cover plate (5) and capscrews. Tightencapscrews to standard torque.

3. If removed, install rear engine mounts (1, Figure4-6) to flywheel housing. Tighten capscrews tostandard torque.

4. Place rubber mount in each rear engine framemount (2, Figure 4-6).

5. Install front engine rubber mounts in frame mounts( 4, Figure 4-7).

6. Place engine lifting tool or equivalent betweencylinder heads, one on each end of engine, underprotruding cast portion. Refer to Figure 4-4. Takeup slack.

Engine weighs approximately 4300 lbs. (1950 kg).Make certain all lifting apparatus is of adequatecapacity.

7. Position engine in frame on rear rubber mounts,start capscrews.

8. Place front cradle (1, Figure 4-7) on front rubbermounts, install capscrews.

9. Install capscrews (2), lockwashers and nuts, se-curing front engine mount to cradle. Tighten tostandard torque.

10. Allow full weight of engine to rest on mounts.

11. Install lower half of rear rubber mounts (3, Figure4-6), large washer and nuts.

12. Tighten nuts until rear rubber mounts are com-pressed between engine mount and frame mountto a dimension of 1.31 in. (33.3 mm). Refer toFigure 4-6.

FIGURE 4-6. REAR ENGINE MOUNT

1. Engine Mount 3. Rubber Mount,2. Rubber Mount, Lower Half Upper Half

FIGURE 4-7. FRONT ENGINE CRADLE MOUNT

1. Cradle Mount 3. Large Washer2. Engine Mount Screws 4. Rubber Mount

FIGURE 4-5. FLYWHEEL ADAPTER

1. Flexible Coupling 4. Capscrews2. Adapter 5. Cover Plate3. Capscrews

C04008 4/90 Engine C4-3

13. Install large washer (3, Figure 4-7) and nut in frontrubber mounts. Tighten nut to standard torque.

14. Front rubber mounts are compressed betweencradle and frame mounts to dimension of 0.94 in(23.8 mm).

15. Connect driveline (6, Figure 4-8) to adapter.Tighten capscrews (3) to 100 ± 5 ft. lbs. (135.6± 7 Nm) torque. Install driveline protector (1 & 5).

16. Connect transmission cooler hoses to transmis-sion and install all clamps.

17. Connect all wires.

18. Connect fuel lines.

FIGURE 4-8. DRIVELINE INSTALLATION

1. Driveline Protector, 4. Capscrews Upper Half 5. Driveline Protector, 2. Capscrews Lower Half3. U-joint Capscrews 6. Driveline

C4-4 Engine C04008 4/90

19. If removed, install throttle cable mounting bracket(3, Figure 4-9) on engine. Tighten capscrews tostandard torque.

20. Connect ATEC throttle potentiometer cable andthrottle cable to fuel pump lever and secure withclevis pin, washers, and cotter pins.

21. Adjust throttle cable to dimension shown in Figure4-9 by loosening locknut (8) and removing clevispin (7). Turn clevis in or out to obtain the properdimensions. Tighten locknut (8) and install throttlecable to fuel pump lever.

NOTE: If dimensions shown cannot be obtained, ad-justment of the mounting bracket (3) may be required.Adjust mounting bracket by loosening the retainingcapscrews (bracket to engine) and moving bracket toallow a closer basic adjustment of linkage. Afterbracket adjustment, tighten capscrews to standardtorque.

22. Install exhaust tubes and support brackets.

23. Make certain air inlet piping is completely cleaninternally. Install tubes and hoses.

Make certain tubes engage rubber elbows andhump hoses properly. Position clamps so elbowsand hump hoses are completely compressed ontubes when clamps are tightened.

24. Install radiator. Refer to instructions covering ra-diator installation, this section.

25. Add oil to proper level. Refer to Section "P", Lubri-cation and Service.

26. Connect battery cables.

27. Start engine, check for leaks and instrument panelgauge readings.

Engine SpeedsLow Idle . . . . . . . . . . . . . . . 700 ± 25 RPMHigh Idle . . . . . . . . . . . . . . . . 2350 RPMGoverned Speed . . . . . . . . . . . . 2100 RPMStall Speed . . . . . . . . . . . . . . . 2070 RPM

Engine Repair

Contact your HAULPAK® Distributor for engine repairor overhaul.

FIGURE 4-9. THROTTLE CABLE INSTALLATION

1. Fuel Pump Lever 3. Cable Mounting Bracket 5. Throttle Cable 7. Clevis Pin and Cotter Pin2. Cable Anchor 4. ATEC Potentiometer Cable 6. Cable Anchor 8. Clevis and Locknut

C04008 4/90 Engine C4-5

NOTES

C4-6 Engine C04008 4/90

AIR FILTRATION SYSTEM

AIR CLEANERAir used by the diesel engine passes through the aircleaner assembly mounted on the right side deck ofthe truck. This dry type air cleaner discharges heavyparticles of dust and dirt by centrifugal action in pre-cleaner sections and then filters finer particles as airpasses through filter elements.

Service Checks

The truck engine must be shut down before serv-icing the air cleaner assembly or opening the en-gine air intake system.

1. Inspect and empty air cleaner dust collector atregular intervals. Daily inspections are recom-mended. Do not allow dust level in the collectorto build up to the Donaclone tube section (pre-cleaner).

2. Before operation or after the engine has been shutdown, observe the air cleaner service vacuumindicator which is located on the left side of thetruck next to the fan shroud. Filter service is re-quired when the indicator shows maximum re-striction.

3. Make certain that the air inlet on the air cleaner isfree of obstruction. Inlet must not be clogged ordamaged.

4. Check engine air intake tube, hoses and clamps.All connections and joints must be air tight toprevent entrance of dirty air.

5. Air cleaner housing fasteners and mountings mustbe tight.

6. After filter service has been accomplished, resetair cleaner service vacuum indicator by pushingthe reset button on top of indicator.

Filter Element Replacement

The truck engine MUST NEVER be operated withelements removed. Engine operation with filterelements removed can cause serious engine dam-age. Run the engine ONLY with the air cleanerassembly completely assembled and closed.

Main filter element restriction is registered by a serviceindicator located on LEFT side of fan shroud. As filterbecomes clogged with dirt, a vacuum differential iscreated by engine demand for air causing indicatorfloat to expose red area. Filter service is needed whenred area is exposed.

1. Shut engine down. Clean area around filter ele-ment cover and remove cover (2, Figure 5-1).

2. Loosen large wing nut (5) on air cleaner to freemain element assembly. Pull main element clearof assembly.

3. Inspect filter element carefully for possible dam-age, holes, breaks, etc., which might affect reuseof element. If element appears serviceable otherthan being dirty, proceed with the cleaning proce-dure. If defects are found, discard element. Wingnut assembly must be removed from elementassembly and installed on new filter element.

Have a new safety (secondary) filter element athand before removing old one. Do not keep intakesystem open to atmosphere any longer than abso-lutely necessary. The indicator in the safety filterelement wing nut will reset by gently blowing airinto threaded hole from the gasket side of wing nut.

C05009 04/98 Air Filtration System C5-1

FIGURE 5-1. AIR CLEANER ASSEMBLY

1. Retaining Clip 4. Safety Filter Element 6. Safety Filter Element 8. Dust Collector2. End Cover 5. Wing Nut Indicator 9. Air Intake Cover3. Primary Filter Element 7. Pre-Cleaner Section

C5-2 Air Filtration System C05009 04/98

4. Check indicator in safety (secondary) filter ele-ment wing nut. If this indicator shows that thesafety element is clogged, the element must bereplaced with a new element. Do not clean safetyelement - discard used element and replace. Re-set indicating wing nut to green by gently blowingair into threaded hole from gasket side of wing nut.Install new safety element and secure with indicat-ing wing nut. Tighten wing nut to 10 ft. lbs. (13N.m) torque.

5. Install clean or new main filter element into aircleaner and secure with wingnut. Tighten wing nuthand tight, do not use a wrench or pliers. If filterelement is being reused, make sure sealing gas-ket is not damaged, the gasket must seal com-pletely.

6. Close and latch the dust collector on the bottomof air cleaner assembly.

Main Filter Element Cleaning

NOTE: Remember that only the main (primary) filterelement may be cleaned, and then only if it is structur-ally intact. Do not reuse any element which is dam-aged. DO NOT clean and reuse the safety (secondary)filter element. Replace this item when clogged ordamaged.

After inspection, determine if the element should becleaned by using either washing or compressed airmethods. If element is clogged with dust, compressedair will clean element. If element is clogged with carbon,soot, oil and/or dust, the complete washing procedurewill produce the best results.

1. Wash elements with water and detergent as fol-lows:

a. Soak the element in a solution of detergent andwater for at least 15 minutes. Rotate elementback and forth in the solution to loosen dirtdeposits. DO NOT soak elements for more than24 hours.

b. Rinse element with a stream of fresh water inthe opposite direction of normal air flow untilrinse water runs clear. Maximum permissiblewater pressure is 40 psi (276 kPa). A complete,thorough rinse is essential.

c. Dry the element thoroughly. If drying is donewith heated air, the maximum temperaturemust not exceed 140oF (60oC) and must becirculated continually. Do not use a light bulbfor drying elements.

d. When the elements is thoroughly clean, inspectcarefully for even the slightest ruptures or punc-tures and for damaged gaskets. A goodmethod to detect ruptures in the paper filtermaterial is to hold a light inside filter element asshown in Figure 5-2 and inspect outer surfaceof element, any holes or ruptures will be easilyspotted. If holes or ruptures are found, do notreuse the element, discard and install a newunit.

2. Clean dust loaded elements with dry, filtered,compressed air:

a. Maximum nozzle pressure must not exceed 30psi (207 kPa). Nozzle distance from filter ele-ment surface must be at least one inch (25 mm)to prevent damage to the filter material.

b. As shown in Figure 5-3, direct stream of air fromnozzle against inside of filter element. This is theclean air side of the element and air flow shouldbe opposite of normal air flow.

c. Move air flow up and down vertically with pleatsin filter material while slowly rotating filter ele-ment.

d. When cleaning is complete, inspect filter ele-ment as shown in Figure 5-2 and if holes orruptures are noted, replace the element with anew item.

FIGURE 5-2. INSPECTING FILTER ELEMENT

FIGURE 5-3. CLEANING FILTER ELEMENT WITHCOMPRESSED AIR


Precleaner Section

The Donaclone tubes in precleaner section of aircleaner assembly should be cleaned at least onceannually and at each engine overhaul. More frequentcleaning may be necessary depending upon operatingconditions and local environment if tubes becomeclogged with oil, sludge or dirt.

To inspect tubes in precleaner section, remove mainfilter element. Do not remove the safety element.Loosen clamps and remove dust collector cup. Use alight to inspect the tubes. All tubes should be clear andthe light should be visible.

Clean the Donaclone tubes as follows if clogging isevident.

Cleaning Precleaner Tubes

Both the main and safety elements must be in-stalled in the air cleaner while Steps 1 and 2 arebeing accomplished to prevent any possibility ofdirt being forced into the engine intake area.

1. Dust can best be removed with a stiff fiber brush.DO NOT use a wire brush. Dust may also becleaned effectively using compressed air.

2. Heavy plugging of tubes may require soaking andwashing of complete precleaner section. The fol-lowing instructions cover these procedures.

NOTE: The precleaner section may be separated fromthe air cleaner assembly without dismounting the com-plete air cleaner from the truck.

3. Loosen clamp and remove dust collector cup (8,Figure 5-1) from precleaner section (7).

4. Loosen clamp and remove the air intake cover (9)and precleaner. The safety element must remainin place to protect the engine intake.

5. Submerge precleaner section in a solution ofDonaldson D-1400 and warm water (mix solutionaccording to package directions). Tube sectionmust be down. Soak for 30 minutes, remove fromsolution and rinse thoroughly with fresh water andblow dry.

6. Severe plugging may require the use of an Oakite202 and water solution. The solution should bemixed 50% Oakite 202 and 50% fresh water. Soakprecleaner section for 30 minutes, rinse clean withfresh water and blow dry completely.

FIGURE 5-4. CLEANING DONACLONE TUBES

FIGURE 5-5. WASHING AND SOAKING OFPRECLEANER SECTION


7. Check precleaner gasket carefully for any evi-dence of air leaks, replace all suspected gaskets.

8. Install precleaner section, with serviceable gasketon air cleaner assembly and replace all mountinghardware removed.

9. With a serviceable gasket, install dust collectorcup assembly on precleaner section and securewith mounting clamps.

Air Intake Troubleshooting

To insure maximum engine protection, be sure that allconnections between air cleaner and engine intake aretight and positively sealed. If air leaks are suspected,check the following:

1. All intake lines, tubes and hump hoses for breaks,cracks, holes, etc., which could allow an intake airleak.

2. Check all air cleaner gaskets for positive sealing.

3. Check air cleaner elements, main and safety, forruptures, holes or cracks.

4. Check air cleaner assembly for structural damage,cracks, breaks or other defects which could allowair leakage. Check all mounting hardware fortightness.


NOTES


ENGINE COMPONENTS

THROTTLE CONTROL The engine is equipped with a multiple position throttlecontrol lever mounted on the Cummins fuel pump. Twocables are attached to the control lever; one cable isconnected to the throttle pedal located in the cab andallows the operator to control engine speed from idleto full throttle. The remaining cable is connected to theATEC Throttle Position Sensor and provides a voltagesignal proportional to the throttle position to the ECU.

THROTTLE CONTROL PEDALRemoval and InstallationRefer to Section ‘‘N’’, Operator Cab, for removal, instal-lation and disassembly of the throttle control pedal.

THROTTLE CONTROL LEVERIf the throttle control lever is removed during fuel pumprepairs or during an engine replacement, it is essentialthat it is properly aligned during installation. Correctalignment will ensure proper throttle pedal and throttleposition sensor cable adjustment. Refer to Figure 6-1.

1. Install brackets for throttle control cable and throt-tle position sensor (TPS). Tighten capscrews tostandard torque.

2. Install the throttle control lever offset 14° fromvertical as shown in Figure 6-2. This position is‘‘idle’’. Tighten the clamping capscrew.

3. At full throttle position, the lever travel should stop14° to the left of the vertical line shown in Figure6-2.

FIGURE 6-1. CUMMINS THROTTLE CONTROL LEVER1. Fuel Pump Lever 3. Cable Mounting Bracket 5. Throttle Cable 7. Clevis Pin & Cotter Pin2. Cable Anchor 4. ATEC Potentiometer Cable 6. Cable Anchor 8. Clevis and Locknut

C06010 6/90 Engine Components C6-1

FIGURE 6-2. THROTTLE AND SENSOR CABLE INSTALLATION

(CUMMINS ENGINE)

1. Throttle Pedal.2. Pedal Start Position

Adjustment3. Stop Limit Screw4. Locknut5. Cable Anchor

6. Throttle Control Cable 7. Throttle Position Sensor

Cable (ATEC - TPS) 8. Mounting Plate 9. Cable anchor10. Machine Screws

16. Jam Nut17. Cable Anchor18. Throttle Position Sensor19. Capscrews20. Electrical Connector

11. Cable Terminal12. Fuel Pump Lever13. Spring14. Clevis Pin15. Clevis

C6-2 Engine Components C06010 6/90

Throttle Control Adjustment

1. Adjust throttle control pedal stop limit screw (3,Figure 6-2) for a comfortable full throttle foot po-sition. Tighten lock nut (4).

2. Adjust pedal start position (2) to obtain 1.30 in. (33mm) of downward travel to the head of the pedalstop limit screw (3). Refer to Figure 6-3.

NOTE: Do not adjust the pedal stop limit screw withoutalso adjusting the pedal start position adjustment.

3. Position cable anchor (5) in holes which permitcable to be fully retracted to the pedal start posi-tion when pedal lever cable (6) is connected withthe governor control lever in the ‘‘Idle’’ position.Secure cable anchor to mounting holes.

4. Loosen cable anchor (17).

5. With fuel pump lever (12) in the ‘‘Idle’’ position,loosen the jam nut (16) on accelerator controlcable clevis (15).

6. Remove the cotter pin and clevis pin (14) fromcable clevis.

7. Adjust the accelerator cable (6) by turning theclevis (15) on or off the cable. Turn the clevis eyeso that it aligns with the eye in the fuel pumpcontrol lever (12) in the ‘‘Idle’’ position.

8. Install clevis pin (14) and cotter pin into clevis andtighten jam nut (16) holding clevis to acceleratorcontrol cable.

9. Tighten cable anchor (17) in position. Check thatthe throttle end of the cable is properly shimmedto prevent the cable from binding during opera-tion and the anchor secures the cable in the cablegroove.

10. Start engine and check out operation of the throttlepedal.

11. Run engine up to full throttle and release. Engineshould return to ‘‘Idle’’ (700 RPM). Cable shouldwork freely without binding.

12. Refer to ‘‘ATEC Throttle Position Sensor’’ for sensorcable installation.


ATEC THROTTLE POSITION SENSOR Figure 6-3 illustrates the operating range of the ThrottlePosition Sensor cable relative to the range of the fuelpump throttle control lever. The Throttle position Sen-sor is self-calibrating providing the cable travel is withinthe ‘‘normal operating range’’.

The cable has a total stroke of approximately 1.88 in.(48 mm) however, the entire range is not usable. Anerror code (to the ECU) will result if the cable is notadjusted properly or mechanical components are wornexcessively. This area is indicated by the ‘‘error zone’’.

The ‘‘functional range’’ allows adequate cable travel toinclude the ‘‘optimum operating range’’ and allow for aslight misadjustment and wear of components beforereaching the ‘‘error zone’’. The ‘‘optimum operatingrange’’ is the desired range to obtain when installingthe throttle position sensor cable.

Total cable stroke can be verified by measuring 3.56 in.(90 mm) from the centerline of the cable clamp to theend of the cable when retracted and 5.44 in. (138 mm)when extended (See Figure 6-3).

Throttle Position Sensor and Cable

Removal

Refer to Figure 6-2 for the engine installation and partsreferences.

1. Remove machine screws (10), shims, and clamp(9) securing the cable to the mounting plate (8).

2. Remove cotter pin, cable terminal (11), and re-move cable (7) from throttle control lever (12).

3. Remove electrical connector (20), capscrews (19)and remove throttle position sensor (18) frommounting bracket.

4. Remove the cable and sensor assembly using careto prevent sharp bends in cable.

FIGURE 6-3. THROTTLE POSITION SENSOR (TPS) CABLE


Installation

1. Position throttle position sensor (18, Figure 6-2)on its mounting bracket and attach with cap-screws (19), washers and nuts. Tighten cap-screws to 10 ft. lbs. (13 N.m) torque.

2. Carefully route cable to the mounting plate locatedat the fuel pump.

NOTE: Adjust the throttle lever, pedal and throttle cableprior to installing the throttle position sensor cable.

3. Install the throttle position sensor cable (7) on themounting plate (8) and install clamp (9) and ma-chine screws.

NOTE: Clamp (9) must positively lock cable in cablegroove. Shim clamp as required to maintain free cableend movement.

4. Verify the cable travel is 1.88 in. (48 mm) measuredfrom the centerline of the cable clamp to the endof the cable. Refer to Figure 6-3.

5. Assemble the cable terminal (11, Figure 6-2) onthe cable end. Attach the hitch pin clip to thecable.

6. Insert the cable terminal through the hole in thethrottle lever arm and insert cotter pin.

7. Verify the following dimensions (Refer to Figure6-3):

a. With the throttle lever in the ‘‘idle’’ position,measure 4.18 in. (106 mm) between the center-line of the cable clamp and the end of the cable.

b. With the throttle lever in the ‘‘full throttle’’ posi-tion, measure 4.94 in. (125 mm) between thecenterline of the cable clamp and the end of thecable.

NOTE: If the dimensions found in step 4 do not fallwithin the ‘‘normal operating zone’’ dimensions shownin Figure 6-3, the throttle lever must be repositionedand the throttle pedal cable adjustment procedurerepeated.

8. Verify the throttle lever can be returned to ‘‘idle’’even though the sensor cable is held in the ‘‘fullthrottle’’ position.

FANRemoval

1. Remove capscrews holding left and right fanguard sections together. Remove capscrewsmounting fan guard to radiator shroud. Removefan guards.

2. Remove capscrews and lockwasher retaining fanand fan adapter to fan drive pulley. Remove fan,fan weighs approximately 63 lbs. (29 Kg.).

NOTE: Check fan for cracks and bent or loose blades.

Replace the fan if the blades are bent or cracked.

Installation

1. Assemble fan adapter to drive pulley and install fanto adapter. Rear edges of fan blades should beapproximately 0.57 in. (14.5 N.m) from the rearface of the fan shroud. Tighten capscrews to 90ft. lbs. (122 N.m) torque.

2. Install either left or right section of fan guard toradiator shroud. Install two capscrews, do nottighten, install other half of fanguard, and installtwo capscrews holding fan guard to radiatorshroud. Align holes, holding two halves togetherand install capscrews. Tighten to 25 ft. lbs. (3.5N.m) torque. Install remaining capscrews holdingfan guard to radiator shroud. Tighten all cap-screws to 25 ft. lbs. (3.5 N.m) torque.

FAN BELT ADJUSTMENT

To prevent injuries, always release spring tensionbefore replacing the fan belt.

HAULPAK® Trucks equipped with CumminsKTA/KTTA19C Engines have a self adjusting springloaded idler assembly. Either a turnbuckle or a shockabsorber is used to limit the travel of the idler pulley.

A grease nipple is standard on the pivot arm. The pivotarm must be greased at each scheduled maintenanceinterval. Also, inspect the shock absorber for fluidleakage and loss of vibration absorption at each sched-uled maintenance interval. For further information onBelt Driven Fan Hub, refer to Cummins K19 Specifica-tions Manual.


ALTERNATOR BELT ADJUSTMENT

Check

Use a Belt Tension Gauge to determine the belt tension.Belt tension must be 165 ft. lb. (220 N.m).

FIGURE 6-4. ALTERNATOR BELT ADJUSTMENT

1. Belt Tension Gauge

Adjustment

1. Loosen the alternator and adjusting link mountingcapscrews. (1, 2, 4, Figure 6-5).

2. Loosen the jam nuts on the adjusting screw (3).

FIGURE 6-5. LOOSENING JAM NUTS

1. Alternator Mounting 3. Jam Nuts Capscrew 4. Capscrew2. Capscrew

3. Turn the adjusting screw clockwise to tighten thebelt tension (2, Figure 6-6).

FIGURE 6-6. ALTERNATOR BELT ADJUSTMENT

1. Belt Tension Gauge 2. Adjusting Screw

Caution: The lower jam nut has left-hand threads.

4. Tighten the jam nuts on the adjusting screw (3,Figure 6-7) to 40 ft. lb. (55 N.m) torque.

5. Tighten the adjusting link and alternator mountingcapscrews (1, 2, 4) to 40 ft. lb. (55 N.m) torque.

FIGURE 6-7. TIGHTENING JAM NUTS

1. Alternator Mounting 3. Jam Nuts Capscrew 4. Capscrew2. Capscrew

6. Check the belt tension again to make sure it iscorrect (1, Figure 6-4).


SECTION DELECTRIC SYSTEM 24VDC. NON-PROPULSION

INDEX

24VDC ELECTRICAL SUPPLY SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . D2-1ELECTRICAL SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . D2-1BATTERY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-1

Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-1Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-1Maintenance and Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . D2-2Spillage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-3

BATTERY CHARGING ALTERNATOR . . . . . . . . . . . . . . . . . . . . . . . . . D2-3Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-3Magnetizing The Rotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-4Regulator Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-4Circuit Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-5

BATTERY CHARGING CIRCUIT COMPONENTS . . . . . . . . . . . . . . . . . . . D2-5BATTERY EQUALIZER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-6

Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-6Circuit Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D2-6

ELECTRICAL SYSTEM COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . D3-1ELECTRICAL CIRCUIT CHECKOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-1HORN, WINDSHIELD WIPER, AND WINDSHIELD WASHER CIRCUITS . . . . . . . D3-1WINDSHIELD WASHER CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-1

Windshield Wiper Circuit Checkout Procedure . . . . . . . . . . . . . . . . . . . . D3-1BRAKE LOCK AND PARK BRAKE CIRCUIT . . . . . . . . . . . . . . . . . . . . . . D3-2

Brake Lock Switch Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-2Brake Lock Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-2Park Brake Switch and Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-2Park Break Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-2

LOW BRAKE PRESSURE SWITCH AND CIRCUIT . . . . . . . . . . . . . . . . . . . D3-2GAUGES AND CIRCUIT COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . D3-2

Circuit Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-2LOW BRAKE PRESSURE WARNING AND INDICATOR LIGHT CIRCUITS . . . . . . D3-3

Circuit Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-3HOIST CONTROL CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-5

Hoist Control Switch Circuit Checkout . . . . . . . . . . . . . . . . . . . . . . . . D3-5BODY - UP LIMIT SWITCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-5

Body-up Limit Switch Circuit Checkout . . . . . . . . . . . . . . . . . . . . . . . . D3-5STEERING BLEEDDOWN TIMER CIRCUIT . . . . . . . . . . . . . . . . . . . . . . D3-5

Circuit Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-6Steering Bleeddown Circuit Checkout . . . . . . . . . . . . . . . . . . . . . . . . D3-6Accumulator Precharge Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-6Engine Shutdown Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-6

LIGHT CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-6Circuit Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-7

HEATER AND AIR CONDITIONER CIRCUIT . . . . . . . . . . . . . . . . . . . . . . D3-7Circuit Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-7Circuit Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-7

D01006 5/92 Index D1-1

24 VDC ELECTRICAL START SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-8OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-8CRANKING MOTOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-8Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-8Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-8

CRANKING MOTOR TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . D3-9Preliminary Inspection3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-9No - Load Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-9Interpreting Results of Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-9Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-10Cleaning and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-12Armature Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-12Field Coil Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-12Field Coil Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-12Solenoid Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-13Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-14Pinion Clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-14

MAGNETIC SWITCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-15Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-15Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-15Coil Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-15

ELECTRIC START SYSTEM WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . D3-16

STARTER, ENGINE 24 VDC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-17Circuit Check - out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D3-17

ALLISON TRANSMISSION ELECTRONIC CONTROL (ATEC) . . . . . . . . . . . . . . . D4-1ATEC SYSTEM OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-1

Range Selector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-1DO NOT SHIFT Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-1CHECK TRANS Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-1

SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-2TRANSMISSION CONTROL CIRCUITS . . . . . . . . . . . . . . . . . . . . . . . . . D4-3

Battery Charging Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-3Control Power And Memory Circuits . . . . . . . . . . . . . . . . . . . . . . . D4-5Start Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-5Check Transmission Warning Light Circuit . . . . . . . . . . . . . . . . . . . . D4-5Backup Horn And Light Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . D4-5Hoist Interlock Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-5Auto/Manual Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-5Overspeed Relay Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-5Speedometer Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-5

TRANSMISSION CIRCUIT COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . D4-6CIRCUIT DESCRIPTION AND CHECKOUT . . . . . . . . . . . . . . . . . . . . . . . D4-7ATEC DIAGNOSTIC CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D4-10

D1-2 Index D01006 5/92

24VDC ELECTRIC SUPPLY SYSTEM

ELECTRICAL SYSTEM DESCRIPTION

The electric system is made up of many circuits thatstart, control, monitor, warn and illuminate the truckduring operation. The HAULPAK truck utilizes a24VDC electrical system which supplies power for allelectrical components except for a 12VDC circuit thatis part of the transmission control. The 24VDC issupplied by two 12 volt storage batteries wired inseries.

When the engine is shut down and keyswitch is ‘‘Off’’,24 volts is supplied through the battery disconnectswitch to the circuits for the alternator, the batteryequalizer, the battery equalizer monitor, engine oilpressure switch, keyswitch, headlight switch, turn sig-nals, hazard flasher, and the steering bleeddowntimer.

A 12 volt signal is present at the battery equalizer, thebattery equalizer monitor and two relays of transmis-sion control circuit and to the E.C.U. of the transmis-sion control circuit to power the memory of the E.C.U.With engine shut down and keyswitch ‘‘Off’’ the maxi-mum current from batteries to memory circuit is 10 mawhich will not appreciably affect batteries. All othercircuits are open at this time.

With engine running and keyswitch ‘‘On’’, all circuitsare capable of operating under the necessary condi-tions for the circuit. Whether a particular circuit iscompleted depends on components in circuit and pur-pose.

Refer to Electrical Schematic, Section ‘‘R’’ for specificcircuit details.

BATTERY

The batteries are of the lead-acid type, each containingsix 2-volt cells. During operation, the storage batteriesfunction as an electrochemical device for convertingchemical energy into the electrical energy required foroperating the accessories when the engine is shutdown.

Lead-acid storage batteries contain sulphuricacid, which if handled improperly may cause seri-ous burns on skin or other serious injuries topersonnel. Wear protective gloves, aprons and eyeprotection when handling and servicing lead--acidstorage batteries. See the precautions in Section ‘‘A’’ of this manualto insure proper handling of batteries and treat-ment for accidents involving sulphuric acid.

Service

As more machines are equipped with electric starters,it is more important than ever to maintain the batteriesin good working condition.

The electrolyte level of each cell should be checked atthe interval specified in the Lubrication and ServiceSection ‘‘P’’, and water added if necessary. The properlevel to maintain is 3⁄8--1⁄2 in. (10-13 mm) above theplates. To insure maximum battery life, use only dis-tilled water or water recommended by the batterymanufacturer. After adding water in freezing weather,operate the engine for at least 30 minutes to thoroughlymix the electrolyte.

DO NOT SMOKE or allow flame around a deadbattery or during the recharging operation. Theexpelled gas from a dead cell is extremely explo-sive.

Excessive consumption of water indicates leakage orovercharging. Normal water usage for a unit operatingeight hours per day is about one to two ounces per cellper month. For heavy duty operation (24 hour) normalconsumption should run about one to two ounces percell per week. Any appreciable increase over thesefigures should be considered a danger signal.

Storage

Idle batteries should not be allowed to stand unat-tended. If equipment is to stand unused for more thantwo weeks, the batteries should be removed andplaced in a cool, dry place where they may be checkedperiodically and charged when necessary.

D02006 4/98 24VDC Electric Supply System D2-1

All batteries will self discharge over a period of time ifnot used and charged. A fully charged battery will lose25% of its power in as little as 30 days in warmweather. A 50% power loss will occur in 60 days. Thisself discharge takes place even though the battery isnot connected in a circuit and is more pronounced inwarm weather than in cold.

The rate of self-discharge of a battery kept at 100°F(38°C) is about six times that of a battery kept at 50°F(19°C) and self-discharge of a battery kept at 80°F(27°C) is about four times that one at 50°F (10°C).

Over a thirty day period, the average self-dischargeruns about 0.002 specific gravity per day at 80°F(27°C).

To offset the results of self-discharge, idle batteriesshould receive a booster charge (not a quick charge)at least once every thirty days. Batteries allowed tostand for long periods in a discharged condition areattacked by a crystallization of the lead sulfate on theplates. Such batteries are called sulfated and are, inthe majority of cases, irreparably damaged. In lesssevere cases, the sulfated battery may be restored tolimited service by prolonged charging at a low rate(approximately 1⁄2 normal rate).

An undercharged battery is extremely susceptible tofreezing when allowed to stand in cold weather.

The electrolyte of a battery in various stages of chargewill start to freeze at temperatures indicated in thetableabove.

The temperatures in the table indicate the points atwhich the first ice crystals appear. Lower temperaturesmust be reached for a solid freeze. Solid freezing ofthe electrolyte may crack the battery case and damagethe positive plates. As will be noted, a 3⁄4 chargedbattery is in no danger of freezing, therefore, a 3⁄4charge or better is desirable, especially during winterweather.

Never attempt to charge a frozen battery. Seriousinjuries can occur.

Maintenance and Troubleshooting

Two most common troubles that occur in the chargingsystem are undercharging and overcharging of thetruck’s batteries.

An undercharged battery is incapable of providingsufficient power to the truck’s electrical system.

Some possible causes for an undercharged batteryare:

Sulfated battery plates

Loose battery connections

Defective wire in electrical system

Loose alternator drive belt

A defective alternator

Overcharging, which causes overheating, is first indi-cated by excessive use of water. If allowed to continue,cell covers will push up at the positive ends and inextreme cases the battery container will become dis-torted and cracked.

A battery can discharge if it is not clean and dry. A fullycharged battery can become discharged to a level lowenough to prevent it from starting an engine in as littletime as one week. The problem may be acid film anddirt lying on top of the battery. This creates a path forelectricity to travel between the terminals, thus dis-charging the battery.

Use either an analog or digital voltmeter to determineif there is a path between the terminals.

a. Set the voltmeter at a range to indicate batteryvoltage.

b. Place the positive lead of the voltmeter on thepositive battery post.

c. Place the negative lead so that it touches thebattery case approximately one inch away fromthe positive post.

Specific GravityCorrected to 80°F (27°C)

Freezing TemperatureDegrees

1.280 -90°F (-70°C)

1.250

1.200

1.150

1.100

-60°F (-54°C)

-16°F (-27°C)

+5°F (-15°C)

+19°F (-7°C)

D2-2 24VDC Electric Supply System D02006 4/98

d. The voltmeter should indicate 0.0 volts. If anyvoltage is indicated, there is a path that will dis-charge the battery. The higher the voltage, thequicker the discharge rate.

e. Move the negative probe to several locations(near the positive post) to verify the test results.

If voltage was detected in the previous test, the batteryshould be cleaned. The top of the battery may be wipedoff with a damp cloth or washed with a baking soda orammonia solution. If the battery is washed, be surenone of the cleaning solution is allowed into the batterycells. Be sure terminals are clean and tight. Cleanterminals are very important in a voltage regulatedsystem. Be sure to clean the entire battery compart-ment thoroughly as it may contain acid residue. Becareful not to splash any overspray onto surroundingcomponents. Rinse the area completely to remove alltraces of battery acid from machine.

Leakage can be detected by continual wetness of thebattery or excessive corrosion of the terminals, batterycarrier and surrounding area. (A slight amount of cor-rosion is normal in lead--acid batteries). Inspect thecase, covers and sealing compound for holes, cracksor other signs of leakage. Check battery hold downconnections to make sure the tension is not greatenough to crack the battery, or loose enough to allowvibration to open the seams. A leaking battery shouldbe replaced.

To remove corrosion, clean the battery with a solutionof ordinary baking soda and a stiff, non-wire brush andflush with clean water.Corrosion creates resistance inthe charging circuit which causes undercharging andgradual starvation of the battery.

NOTE: When washing batteries, make sure cell capsare tight to prevent cleaning solution from entering thecells.

Maintaining clean batteries will provide longer servicelife and a higher rate of performance.

Spillage

Addition of acid will be necessary if considerable elec-trolyte has been lost through spillage. Before addingacid, make sure battery is fully charged. This is accom-plished by putting the battery on charge and takinghourly specific gravity readings on each cell. When allthe cells are gassing freely and three successivehourly readings show no rise in specific gravity, thebattery is considered charged. Additional acid may

now be added. Continue charging for another hour andagain check specific gravity. Repeat the above proce-dure until all cells indicate a specific gravity of 1.260-1.265 corrected to 80°F (27°C).

NOTE: Use 1.400 strength sulphuric acid when mak-ing specific gravity adjustments. Acid of higherstrength will attack the plates and separators before ithas a chance to diffuse into the solution.

If the temperature of the electrolyte is not reasonablyclose to 80°F (27°C) when the specific gravity is taken,temperature should be corrected to 80°F (27°C):

• For every 10°F (5°C) below 80°F (27°C), 0.004should be SUBTRACTED from the specific gravityreading.

• For every 10°F (5°C) above 80°F (27°C), 0.004should be ADDED to the reading.

BATTERY CHARGING ALTERNATOR

A 24 volt alternator is used to supply electric currentfor the 24VDC circuits when the engine is running. Thealternator is equipped with an internal regulator systemused to keep the batteries at full charge. Internaldiodes convert the alternator’s AC output to DC.

The only movable part in the assembly is the rotor,which is mounted on a ball bearing at the drive end anda roller bearing at the rectifier end. All current carryingconductors are stationary. These conductors are thefield winding, the stator windings, the six rectifyingdiodes and the regulator circuit components. The regu-lator and diodes are enclosed in a sealed compart-ment.

A fan located on the drive end provides air flow forcooling. Grease reservoirs contain an adequate supplyof lubricant so that no periodic maintenance is re-quired. For repair or maintenance contact your localDelco-Remy Distributor.

NOTE: The hex head bolt on the output terminal iselectrically insulated; no voltage reading can be ob-tained by connecting to the hex head.

Operation

The basic operating principles are explained as follows(Refer to Figure 2-1):

As the rotor begins to turn, the permanent magnetismtherein induces voltages in the stator windings. Thevoltages across the six diodes cause current to flow tocharge the battery.


Current from the stator flows through the three diodesto resistor R6 and the base-emitter of TR2 and TR1 toturn these transistors on. Current also flows from thestator through the diode trio D1, D2 and D3, the fieldcoil and transistor TR1, returning to the stator throughthe other three diodes. All stator current, exceptthrough the diode trio D1, D2 and D3, flows throughthe six diodes connected to the stator.

Current flow through R1, R2 and R3 causes a voltageto appear at zener diode D4. When the voltage be-comes high enough due to increasing generatorspeed, D4 and the base-emitter of TR3 conduct cur-rent and TR3 turns on. TR2 and TR1 then turn off,decreasing the field current and the system voltagedecreases. The voltage at D4 decreases, D4 and TR3turn off, TR2 and TR1 turn back on and the systemvoltage increases. This cycle then repeats many timesper second to limit the system voltage as determinedby the setting of the potentiometer R2.

Capacitor C1 protects the generator diodes from hightransient voltages and suppresses radio interference.Resistor R5 prevents current leakage through TR3 athigh temperatures. Diode D5 prevents high transientvoltages in the field coil when the field current isdecreasing.

Resistor R7, capacitor C3 and resistor R4 all act tocause transistors TR2 and TR1 to turn on and off morequickly.

FIGURE 2-1. ALTERNATOR & REGULATOR SCHEMATIC

FIGURE 2-2. VOLTAGE ADJUSTMENTPOTENTIOMETER

1. Regulator CircuitBoard

2. Voltage AdjustmentPotentiometer


Magnetizing The Rotor

The rotor normally retains magnetism to provide volt-age build-up when the engine is started. After disas-sembly or servicing, however, it may be necessary toreestablish the magnetism. To magnetize the rotorconnect the alternator to the battery in a normal man-ner, then momentarily connect a jumper lead from thebattery positive post to the relay ‘‘R’’ terminal.

Regulator Adjustment

When there are indications that the 24 volt batteriesare being over-charged or under-charged, an adjust-ment can be made to the charging rate of the voltageregulator system.

NOTE: Prior to adjusting the voltage regulator, verifyproper operation of the battery equalizer. Refer to step14. in ‘‘Commercial Electronic Control (ECU)’’ in thisSection.

1. Remove the cover spacer and plate from the endof the unit to get access to the voltage regulator.

2. Partially remove the silicone rubber from theregulator potentiometer so that the adjustmentscrew can be seen (Figure 2-2).

3. Connect a voltmeter across the terminals of thebatteries and measure the voltage.

NOTE: The batteries must be 75% charged for thismeasurement. (1.240 specific gravity).

4. Adjust regulator potentiometer (2, Figure 2-2) untilsystem voltage measures 27.4 volts. The voltageoutput of the regulator increases by turning theadjusting screw clockwise, or decreases whenturned counterclockwise. If the system’s voltagecannot be adjusted properly or is very erratic, theregulator system requires repair.

5. After the system has been adjusted, put a layer ofsilicone rubber sealant on the adjustment screwto protect the voltage setting.

6. Install cover on end of unit.

Circuit Checkout

1. Check alternator drive belt tension, refer to ‘‘Alter-nator Belt Adjustment’’ procedure in Section ‘‘C’’,Engine Components.

2. With engine at idle, turn on all electrical equip-ment.

3. Connect voltmeter from output terminal of alter-nator to ground.

4. Slowly increase engine RPM, voltmeter readingshould increase to 26-28 volts.

5. If voltage does not increase, refer to RegulatorAdjustment. Refer to Section ‘‘R’’, Electrical Sche-matic.

BATTERY CHARGING CIRCUITCOMPONENTS

Batteries - Two 12 volt batteries located on the righthand deck and connected in series provide 24VDC forthe Truck electrical system and 12VDC for CEC.

Alternator - Is located on the upper right front cornerof the engine, 26-28 volt output capable up to 75amperes.

Battery Equalizer - The equalizer is located in the cabunder the transmission shift selector tower, near theright side of the cab.

Battery Equalizer Monitor - Monitors the batteryequalizer and is located behind the operator’s seatunder the auxiliary seat. The monitor will activate theEQUAL FAULT and/or ALT FAULT lights in the instru-ment panel if a problem is determined. The EQUALFAULT light will illuminate if more than 0.85 voltsvariance is detected between the two 12 volt batteries.The ALT FAULT light will illuminate if the alternator ischarging more than 30 volts or less than 24 volts.

Voltmeter - Is located on the left side of the instrumentpanel and indicates the output voltage of the batterycharging alternator. Normal indicated voltage at highidle is 27 -- 28 volts. When the key switch is ‘‘On’’ andengine is not running, the voltmeter indicates batteryvoltage.

Battery Disconnect Switch - A battery disconnectswitch (large switch) is located on the left side of theCummins engine to disconnect all battery power ex-cept to the CEC components. A separate toggle switchis included between the batteries and the batteryequalizer to disconnect the equalizer and CEC trans-mission control circuits.


Before welding on truck, be certain that each ofthese components are completely disconnected:

• Battery Equalizer

• CEC ECU

• Batteries

• Battery Charging Alternator

To prevent possible damage to the battery equalizer,turn off CEC disconnect switch PRIOR TO disconnect-ing the batteries. Proceed as follows:

1. ALWAYS remove equalizer GND (-) terminalFIRST.

2. Remove +12V (output) terminal at equalizer.

3. Remove +24V (input) terminal at equalizer.

When connecting battery equalizer, use ‘‘Install’’in place of ‘‘Remove’’ and REVERSE the order ofthe above procedure. Be certain GND (-)terminal of equalizer is connected LAST. Fail-ure to do so will damage the equalizer.

4. Disconnect truck batteries:

a. Remove the battery 12V positive (+) terminal(series connection between batteries). DONOT LET TERMINAL TOUCH CHASSISGROUND!

b. Remove the battery 24V positive (+) terminal.

c. Remove the battery 24V negative (-) terminal.

When connecting batteries, use ‘‘Install’’ in placeof ‘‘Remove’’ and REVERSE the order of theabove procedure.

Battery Equalizer - Theory Of Operation

The battery equalizer is an energy transfer device. Itallows power to be taken from a 24 volt battery systemat 12 and 24 volts simultaneously.

The equalizer is designed to be connected to thebatteries continuously, much like an alternator. Theamount of continuous duty 12 volt current is limited tothe size of the equalizer. The equalizer causes the 12volt current draw to be taken from both the batteries ofthe 24 volt system. For example, if a 10 amp, 12 voltload is presented to the system, 5 amps would besupplied by each of the batteries. Any imbalance be-tween the batteries is automatically equalized.

Purpose:

Transmissions equipped with the Commerical Elec-tronic Controls (CEC) require a 12 VDC power supply.On the HAULPAK truck the 12 volt power is throughthe use of only one of the two 12 volt batteries. Sincethe two 12 volt batteries are connected in series, thetransmission controls would use more voltage out ofone battery. The remaining battery would not be re-charged and would eventually lose power to the pointthat the truck would not shift properly or could not berestarted if shut down.

To prevent unequal charge and discharge of the bat-teries, a battery equalizer is provided in the chargecircuit to balance the charge and discharge of bothbatteries.

The equalizer is equipped with a circuit breaker forinternal protection. If the breaker is activated, it mustbe reset to prevent discharging of one battery. Thefault causing the breaker to activate must be corrected.

Refer to Electrical Schematic in Section ‘‘R’’.

Troubleshooting

1. Carefully remove the ground (Gnd) cable from theequalizer. Do not allow this cable to touch anyother connection on the equalizer because theother terminals are connected to the batteries.

2. Make sure there is approximately 12 volts be-tween the +24 and +12 terminals of the equalizerby momentarily connecting the two terminals of a12 volt light (headlight, marker light, etc.) to the+24 and +12 terminals of the equalizer. The lightshould light and stay lit.


3. Next, connect that same 12 volt load between the+12 and gnd terminals of the equalizer. The lampshould light and stay lit. If the lamp does not light,or light then goes out, the equalizer requiresrepair.

4. Further verification may be made by measuringthe voltages on the equalizer terminals. Be cer-tain that the lamp used earlier is connected be-tween the +12 and gnd terminals.

5. Measure the voltage between +24 and +12 termi-nals. Note this reading.

6. Measure the voltage from the +12 terminal to gnd.Note this reading.

7. Compare the two readings by subtracting the [+12to gnd] reading from the [+24 to +12] reading. Aproperly functioning equalizer is one where thedifference is between -0.5 and +0.13 volts. If thedifference between the two voltage readings ismore than 0.75 volts, replace the equalizer. Refer to Electrical Schematic, Section ‘‘R’’.

Battery Equalizer Monitor

The Battery Equalizer Monitor senses several criticalfunctions of a dual voltage (24/12 VDC) vehicle elec-trical system. It is typically used in conjunction with aBattery Equalizer.

The Battery Equalizer Monitor is wired to the system’sground, 12 volt DC, 24 volt DC, and +24V ignition. Bymonitoring the two DC voltages, it can detect faultconditions including battery voltage high (over 30.0volts), battery voltage low (under 24.0 volts), and bat-tery balance. A battery balance fault condition occurswhen the 12 VDC input is outside the range of (24VDCinput ÷ 2) ±0.75 volts. Monitoring takes place onlywhen the ignition is switched on. When a fault conditionis detected, the Monitor provides fault output signalsthat are switched to ground. These outputs can oper-ate external warning lamps, alarm buzzers, or controlrelays, and are rated for 375 milliamps (0.375 amps)DC.

The outputs are short-circuit protected and are de-signed so they may be paralleled, if less than threeexternal lights are desired. It it also possible to installmomentary light test switches (or just one light testswitch, if three isolating diodes are installed) whichenable the operator to check the lamps to determine ifthey are functioning.

Battery Equalizer Monitor Features:

* Designed for two 12 volt batteries operating at 24Volt DC.

* Detects battery high voltage, low voltage, and outof balance conditions.

* Continually monitors vehicle’s electrical system.

* Operates status/warning lamps, control relays, oralarms.

Inputs

Ground (-)+12 VDC +24 VDC Battery +24 VDC Ignition Switch

Outputs

Battery High Voltage Battery Low Voltage Battery Balance.

NOTE - Outputs are open collector, switched toground, 375 milliamp maximum.

Fault Conditions

Battery High Voltage (+24VDC Input Over 30VDC)

Battery Low Voltage (+24VDC Input Under 30VDC)

Battery Balance : +12VDC Input Over (+24VDC Input÷2) +0.75 volts, or, +12VDC Input Under (+24VDC Input÷2) - 0.75 volts


NOTES


ELECTRICAL SYSTEM COMPONENTS

ELECTRICAL CIRCUIT CHECKOUTThe components described in this section have a "cir-cuit checkout" procedure listed after each individualcomponent circuit. The checkout is a guideline fortroubleshooting the electrical system components.

A very important factor, and often overlooked in elec-trical troubleshooting, is wire connections. Beforechanging out electrical components which are non-functional, check the wire connections.

The following basic steps may eliminate many electri-cal problems.

1. Check all cable connections at both batteries.They should be clean with no corrosion. If neces-sary, remove cables and clean connectors with abaking soda - water solution, and a stiff non-wirebrush. Flush with clean water. Install and tightensecurely.

2. Check that connectors are properly crimped ontowires or cables. Improperly crimped connectorscan cause possible overheating of a circuit due tohigh resistance in the connection.

3. Use proper wire gauge and connectors whenmaking wire splices or repairs.

4. Be certain that wire harness is supported properlyand no chafing of wires can occur.

5. Use the correct amperage fuses when replacingfuses. If a circuit calls for a 10 amp fuse, do notreplace with a higher amperage fuse.

6. Do not overload a circuit. If a component is addedto a circuit, be certain that circuit can handle theextra load.

If a problem still exists with a particular component andits circuit after following all the steps above, refer to thecircuit checkout for that particular component and itscircuit.

The electrical schematic in Section "R" should be usedto assist in voltage checks, and the origin of wirenumbers used in the electric wire harness. After follow-ing a proper circuit checkout, it will be easier to deter-mine whether component replacement is necessary.

HORN, WINDSHIELD WIPER ANDWINDSHIELD WASHER CIRCUITS

The horn switch when held closed provides ground forhorn relay coil, closing the normally open (N/O) switchin horn relay will provide 24 volts to the horn. A varistoris used across the relay coil to prevent electrical systeminterference when the horn relay coil de-energizes.

Horn Switch - Is located in the center of the steeringwheel. Is normally open (N/O) provides a ground forthe electric horn.

Electric Horn - Is mounted next to lower left corner ofthe radiator and is grounded through the mountingbase.

WINDSHIELD WASHER CIRCUITThe windshield washer switch, when closed providesa ground for the windshield washer pump motor allow-ing wash solution to be sprayed on the windshield.

Windshield Washer Switch - Is located on the instru-ment panel. It is normally open (N/O), and when closedit provides ground for windshield washer motor.

Windshield Washer Motor - Is located behind theoperator seat mounted on windshield washer reservoirand is attached to the auxiliary seat.

Windshield Wiper Circuit

The windshield wiper switch is supplied 24 volts fromkeyswitch through a 15 amp fuse; ground is providedthrough wiper motor mounting surface. Refer to "Elec-trical Schematic" for windshield wiper circuit.

Circuit Components

15 amp Fuse - The windshield wiper circuit has a 15amp dual element time delay (slow blow) type fuse. Itis located in the instrument panel.

Wiper Switch - Is located on the left side of the instru-ment panel. Switch is "Off-Lo-Hi". "Off" position enablesthe wipers to return to "Park" position.

Windshield Wiper Circuit Checkout Procedure

1. Check 15 amp fuse located in instrument panel. Iffuse is good, proceed to Step 2.

2. Remove cover on inside of cab above windshield.Check for continuity at wiper motor. Refer to Elec-trical Schematic, Section "R" for low voltage checkpoint.

D03006 5/92 Electrical System Components D3-1

3. Using a voltmeter make voltage checks at wind-shield wiper motor connectors.

a. Place windshield wiper switch in "OFF" position.24 volts should be present at wires 31B and 53.

b. Place switch in "Low" position. 24 volts shouldbe present at wire 53.

c. Place switch in "High" position 24 volts shouldbe present at wire 53B.

BRAKE LOCK AND PARK BRAKECIRCUITSBrake lock and park brake circuits have switches andindicator lights located in instrument panel. These areilluminated when actuated by "On-Off" rocker switches.

Brake Lock Switch Circuit

The brake lock solenoid valve and coil are mounted onthe brake manifold which is attached to the servicebrake treadle valve. When the brake lock switch isapplied, a ground is provided for the brake lock indica-tor light. The brake lock solenoid valve coil will ener-gize, shifting the valve and allowing brake accumulatorpressure to apply the rear brakes only. The brake lockshould be used at truck dump and loading areas, notfor extended parking.

Brake Lock Checkout

1. Check for 24 volts at the Brake Lock Switch andsteering bleeddown relay. If the circuit is not com-plete when the Brake Lock Switch is "On", refer toElectrical Schematic, Section "R", for location har-ness connector pin and voltage checks.

2. If the above checkout is complete, check the brakelock solenoid in the brake manifold. If 24 volt ispresent at the solenoid and valve will not shiftreplace solenoid.

Park Brake Switch and Circuit

When the park brake switch (normally open, brakesreleased) is closed it will energize the coil side of therelay, which provides a ground for the illuminated parkbrake switch. The switch side of the relay normallyclosed (N/C) will open, losing the ground to the coil onthe park brake solenoid. The solenoid located in theauxiliary manifold, mounted on the inside of the framenear the right hoist cylinder will shift, blocking off oilsupply to the parking brake actuator. The actuatorwhich is spring applied, hydraulic released will over-come hydraulic pressure and apply park brake.

Park Brake Checkout

1. If park brake won’t apply check for 24 volts at ParkBrake Switch. If the circuit is not complete with thepark brake switch "On" refer to electrical sche-matic. Section "R", for location of harness connec-tor pin and voltage checks.

2. If the circuit is complete, check the park brakesolenoid located in the auxiliary manifold. If 24volts is present at solenoid and valve won’t shiftreplace solenoid.

LOW BRAKE PRESSURE SWITCH ANDCIRCUITIf the brake accumulator supply pressure decreases toapproximately 2000 psi (14 Mpa), the low brake pres-sure warning switch (located in the Low-PressureBrake Detection module) closes. This supplies powerto the coil side of the low brake pressure relay (locatedbehind the instrument panel). When energized, theswitch side of relay will close providing a ground for thelow brake pressure indicator light. The light is supplied24 volts from the keyswitch, through a 5 amp circuitbreaker on the instrument panel and will illuminatewhen grounded.

An audible alarm is also part of this circuit and willsound when low brake pressure relay switch closes atapproximately 2000 psi (14 Mpa). the alarm is locatedin the upper right hand corner of the instrument panel.

For lamp test purposes the warning light circuit uses acommon ground. Diodes are used to prevent any falseindications that can occur from 24V reversing its pathand illuminating other indicator lights, when only oneor more warning light circuits are energized.

GAUGES AND CIRCUIT COMPONENTSThe gauges receive 24 volts from the keyswitch whilethe sending units provide a variable ground to indicateindividual readings. Sending units or sensors are usedto send a signal to the gauges which are used forengine oil pressure, engine water temperature, trans-mission oil temperature. Refer to Electrical Schematic,Section "R".

Circuit Components

Transmission Temperature Gauge - is located on theleft side of the instrument panel and indicates transmis-sion oil temperature.

D3-2 Electrical System Components D03006 5/92

Transmission Temperature Sensor - Is located in theconverter out port on the left side of the transmission.It provides a variable ground for transmission tempera-ture gauge.

Transmission Pressure Gauge - Is located on the leftside of the instrument panel. It indicates transmissionoil pressure.

Transmission Pressure Sensor - Is located in themain regulator valve on front top side of converterhousing It provides a variable ground for transmissionpressure gauge.

Engine Temperature Gauge - Is located on the leftside of the instrument panel. It indicates engine coolanttemperature.

Engine Temperature Sensor - Is located in the enginethermostat housing and provides a variable ground forthe engine temperature gauge.

Engine Oil Pressure Gauge - Is located on the left sideof the instrument panel. It indicates engine oil pressure.

Engine Oil Pressure Sensor - Is located in the engineoil filter head on the left side of the engine block andprovides a ground for engine oil pressure gauge.

Engine Oil Pressure Switch - Is located in the engineoil filter head. It provides 24 volts for check trans relayand oil pressure indicator relay when closed. It is anormally open (N/O) switch and closes at 3-6 psi(20.6-41 kPa).

Brake Temperature Gauge- Is a 24 volt gauge locatedon the left side of the instrument panel. The gaugeindicates the temperature of the hydraulic brake oil.

Hydraulic Brake Oil Temperature Sensor - Is locatedon the back of the hydraulic tank in lower front corner.It provides a variable ground for the brake temperaturegauge.

Speedometer - Is located in the instrument panel nextto tachometer. A signal originating at the transmissionoutput shaft sensor is sent to the ECU. The ECUsupplies an output through ATEC wire 205 to thespeedometer which will indicate MPH or KPH. A noisefilter is used in the speedometer circuit to preventinterference.

Tachometer - Is located in the center of the instrumentpanel. It measures the engine’s R.P.M. The Hourmeteris an integral part of the tachometer and activates whenkeyswitch is turned to "Run" position.

Tachometer Sender Generator - Is located on the fuelpump accessory drive. It provides anAC voltage signalat a frenquency (Hz) proportional to engine speed. The

signal produced is sent to the tachometer and is con-verted to an RPM reading.

Circuit Checkout

Refer to Electrical Schematic, Section "R", for "Termi-nal" location of gauges and voltage checks. Check for24 volts at terminal "B" and "I", insure ground at "G" and"S" terminal.

LOW BRAKE PRESSURE WARNINGAND INDICATOR LIGHT CIRCUITS Three warning and indicator light clusters are locatedon the instrument panel to monitor conditions of theengine, transmission and hydraulic system. A total of12 indicator and warning lights are used.

Cluster 1 contains Low Brake Pressure Warning, LowSteering Pressure, Park Brake and Brake Lock Indica-tor Lights.

Cluster 2 contains Engine Oil Pressure, Coolant Level,Transmission Main Pressure Filter and Engine Tem-perature Indicator Lights.

Cluster 3 contains Accumulator Precharge, Transmis-sion Oil Cooler Filter, Hydraulic Filter, and the BrakeTemperature Indicator Lights.

The bulbs of all four clusters are suppled 24 volts fromkeyswitch through a 5 amp circuit breaker. Each indi-cator bulb has two grounds. Closing the test switchprovides a ground path to indicate all bulbs are oper-ating.

The other ground is through a switch or relay for thesystem or component being monitored. The Low BrakePressure Light and Low Steering Pressure Lights oper-ate along with an audible alarm. Refer to ElectricalSchematic, Section "R".

Circuit Components

Indicator Light Clusters - Are located in the instru-ment panel. The 24 volt bulbs can be replaced from theback side of the instrument panel. Instrument panel tiltsforward for easy access.

Warning Alarm - Is located on the right side of theinstrument panel. Alerts the operator of low steeringand low brake pressure.

Lamp Test Switch - Is located below the indicator lightclusters. When applied it provides a ground for indica-tor lamp testing. Receives 24 volts from key switch.


Low Brake Pressure Relay - Is located on the back ofthe instrument panel. The normally open (N/O) switchside of the relay when closed provides a ground for thelow brake pressure indicator light.

Park Brake Indicator Pressure Switch

The park brake indicator light will be illuminated whensupplied 24 volts from the keyswitch through a 5 ampcircuit breaker, and is grounded through the normallyclosed (N/C) park brake pressure switch. The pressureswitch closes at approximately 500 psi (3.5 MPa) ofdecreasing pressure. With the switch closed, it ener-gizes the park brake relay coil and opens the switchside of the ATEC system wire 222 prohibiting any shiftsof the transmission.

When the park brake is released, hydraulic pressurerises approximately above 500 psi. The pressure switchwill open, losing its ground to the park brake indicatorlight de-energizing coil side of relay and opening theswitch side of the ATEC wire 222 park brake relay,allowing shifts of the transmission to be made.

Low Steering Pressure Switch - Is located on theauxiliary manifold valve assembly. A normally closed(N/C) switch, it is set to close at approximately 1800 psi(12.6 MPa) decreasing pressure. When closed it pro-vides a ground for low steering pressure indicator lightand an audible alarm.

Coolant Level Module - Is supplied 24 volts throughthe keyswitch and a 5 amp circuit breaker to the 24 voltside of the coolant level module. The module has a builtin time delay to eliminate false light indications whileoperating on irregular terrain. The module ground isprovided by mounting on a plate, accessed by remov-ing a cover on the front of the cab.

Coolant Level Probe - Is supplied 24 volts, 80 milliam-pere of current, from the "probe terminal" of the coolantlevel module. The probe is located in the top radiatortank and is submersed in coolant which also serves asa ground for the module.

Coolant Level Relay - Is supplied 24 volts from the"out" terminal of the coolant level module. When thecoolant level goes below the probe in the radiator,ground will be lost and 24 volts will be provided to thecoil side of the relay. The normally open (N/O) switchside of the relay will close and provide a ground for thecoolant level indicator light located in the instrumentpanel, allowing the light to illuminate indicating lowcoolant level.

Engine Oil Pressure Indicator Relay - Is located onthe back of the instrument. It is a normally closed (N/C)switch. When the key switch is turned on the relay

provides a ground for the engine oil pressure indicatorlight. When the engine is started the engine oil pressureswitch closes at approximately 3-6 psi (21-41 KPa)energizing the coil in the relay, allowing the relay switchto open losing the ground to the indicator light andturning it off.

Transmission Filter Warning Switch - Is located inthe head of the transmission main pressure filter as-sembly. Located on the right front corner of the trans-mission, the switch closes at 16 psi. The switchprovides a ground for indicator lamp, indicating a filterrestriction.

Engine Temperature Switch - Is located in the enginethermostat housing. A normally open (N/O) switchwhen closed provides a ground for engine temperatureindicator light. Switch closes at approximately 200°F(93°C) increasing.

Accumulator Precharge Relay - Is located on theback side of the instrument panel. Coil and switch sideof relay are 24V. Coil side may be grounded by any ofthe three accumulator nitrogen precharge switches. Ifany of the three accumulators nitrogen precharge isbelow 850 psi (6 MPa) when keyswitch is turned "On",indicator light will come "On", when coil is energized.Switched side closes to ground, keeping light on aftertruck is started and accumulators are charged. It willbe necessary to determine which accumulator switchis closed if indicator light remains on.

Accumulator Nitrogen Precharge PressureSwitches - One switch is located in the top of eachaccumulator, mounted behind right hand front decksupport. A normally closed (N/C) switch, it has con-tacts set to close at 850 psi (6 MPa) decreasing pres-sure. When closed, it provides ground for prechargerelay coil and warning light.

Cooler Filter Warning Switch (Transmission Con-verter Oil) - Is located in the head of the filter assemblyon the left front corner of the transmission. A switchcloses at 16 psi (112 MPa). The switch provides aground for the cooler filter indicator lamp indicating arestriction in the filter.

Hydraulic Filter Warning Switch - Is located in thehead of the filter assembly mounted on rear surface ofhydraulic tank. Switch is set to close at approximately35 psi (25 MPa), indicating a filter restriction.

Brake Temperature Warning Switch - Is located inlower corner of hydraulic tank. It is set to close atapproximately 250°F (121°C) providing a ground for thebrake oil temperature warning light.


HOIST CONTROL CIRCUITThe hoist control switch is a two pole-manual positionswitch located on the left side of the operator seat; it issupplied 24 volts from the keyswitch. Lifting the switchcontrol lever up will supply 24 volts to the normallyclosed (N/C) body-up limit switch and to the hoist relay.The hoist relay energizes the coil in the hoist up sole-noid, causing the hoist valve to shift and allow hydraulicoil to flow to the hoist cylinders and raise the body.When the operator releases the control switch, or if thebody-up limit switch is de-energized by the body indi-cator arm, the hoist up solenoid will be de-energized.Hydraulic pressure is shut off and the hoist valve willshift into hold position. When the control switch ispushed down, this energizes the hoist down solenoidusing hydraulic oil to shift the hoist valve the oppositeway allowing hydraulic oil to drain back to tank andlowering the body. The hoist up and hoist down sole-noids are located in the auxiliary manifold mounted tothe right hoist cylinder mount structure. When notoperating hoist up or down, lever must be in floatposition. Refer to Electric Schematic, Section "R".

Hoist Control Switch Circuit Checkout

1. With keyswitch "On", and using a voltmeter, movehoist lever to power down, check for 24 volts andmagnetism at coil retaining nut of double solenoidvalve cartridge on auxiliary manifold.

2. Move hoist lever to "Raise" position, again checkfor 24 volts and magnetism on retainer nut. Mag-netism will be greater with lever in "Raise" position,as this is outer coil.

3. If no magnetism in either position, verify solenoidhas an adequate ground check further in circuit.Refer to Electric Schematic, Section "R".

BODY-UP LIMIT SWITCH The body-up limit switch is mounted to the inside framerail near the upper rear suspension mount. It is a singlepole, double throw, normally closed (N/C) magneticactuated proximity switch. The switch is supplied 24volts when the hoist control switch is placed in the"power-up" position only. When the body hoist cylin-ders near full extension, a plate (indicator arm)mounted to the body pivot ear will pass by the sensingarea of the body-up switch. The switch will open, losingthe ground to the hoist solenoid and allow the hoistshuttle valve to shift, blocking off oil supply to the hoistcylinders. This will prevent the body from travelling"over-center" and damaging the hoist cylinders. Theswitch and indicator arm must be properly adjusted for

the switch to work. Refer to Section B, Structures, for"Body-Up" switch adjustment.

Body-Up Limit Switch Circuit Checkout

1. Remove four screws from access plate at end ofswitch. Turn keyswitch "ON" and using a voltmeterperform the following checks.

2. Place hoist control switch in "power-up" position.First check terminal marked "C" for 24 volts. If notpresent check for open circuit back to hoist con-trol switch.

3. Check for 24 volts at terminal "NC". If 24 volts isnot present at "NC" body-up switch is defective,and must be replaced.

4. If Steps 2 and 3 check out, simulate "body-up" byactuating switch. Check terminal "NC" for 24 volts.No reading should occur indicating switch is op-erating properly.

5. Install access plate and screws onto switch.Tighten to standard torque.

STEERING BLEEDDOWN TIMERCIRCUITA manual reset 15 amp circuit breaker located on theinstrument panel supplies 24 volts to the 24 volt positiveterminal of steering bleeddown timer. Ground is pro-vided when the timer is installed on its mounting sur-face.

The keyswitch and an engine oil pressure switch eachsupply the steering bleeddown relay and control termi-nal of the steering bleeddown timer 24 volts throughtwo diodes. The load terminal is connected to steeringbleeddown solenoid valve coil. The remaining terminalis grounded. If engine is not running and key switch isturned "On", the timer is signaled and prepared fortiming function. Turning "Off" keyswitch begins timeroperation. A L.E.D. light on timer indicates timer isoperating, the operating cycle is approximately 90seconds.

During timer operation the bleeddown valve coil lo-cated in the brake manifold is supplied 24 volts. Theenergized coil will shift the steering bleeddown valveallowing hydraulic steering oil to be drained back totank.

When engine is running, turning off keyswitch does notturn on timer as control terminal of timer is suppled 24volts from oil pressure switch. The engine must be shutdown to turn on timer. Refer to Electric Schematic,Section "R".


Circuit Components

15 Amp Circuit Breaker - Is located on the instrumentpanel, manual reset.

Steering Bleeddown Timer - Is mounted on a panelthat can be accessed by removing a plate located onthe front of truck cab. Ground is provided throughmounting base of the timer

Steering Bleeddown Coil - Is located on the brakemanifold valve and is used to shift the steering bleed-down solenoid valve.

Steering Bleeddown Circuit Checkout

1. Shut down engine, wait 90 seconds, rotating steer-ing wheel should not turn front wheels. this willindicate system is operating properly.

2. If front wheels turn when steering wheel is rotated,steering accumulator has not bleddown.

3. Turn "On" keyswitch, turn "Off" keyswitch, checkfor magnetism at steering bleeddown solenoidvalve coil retainer nut. Coil should be energizedfor 90 seconds after keyswitch is turned "Off".

4. If coil is not energized, refer to Electric Schematic,Section "R". Using a voltmeter, check for 24 voltsat control terminal of timer.

5. If coil is energized, check valve portion of steeringbleeddown valve assembly.

Accumulator Precharge Circuit

The instrument panel accumulator precharge warninglight comes "ON" only at start-up when the Key Switchis turned "ON" if the nitrogen precharge in the accumu-lator is "LOW". Once the light is "ON", a latching relaykeeps the light illuminated.

When the operator starts the engine hydraulic pressurebuilds up. As hydraulic pressure builds up in the accu-mulator, so does the nitrogen pressure which causesthe nitrogen pressure switch to open. However, thelight remains "ON" because of the latching relay. Thisis a WARNING to the operator that the accumulatornitrogen precharge was "LOW" in the accumulator atstart-up. The accumulator should be serviced as soonas possible with the proper nitrogen precharge. Referto Accumulator Charging Procedure, Section "L" .

Engine Shutdown Circuit

Engine Shutdown Switch - Is mounted on the instru-ment panel. It is a spring-loaded, normally closed (N/C)switch. When this switch is opened, the coil for the fuelshut-off valve solenoid is de-energized which shifts thevalve and stops fuel flow to the fuel pump.

The Engine Shutdown Solenoid - is located on top ofthe fuel pump on the left side of the Cummins engine.

Refer to Electric Schematic, Section "R" for CircuitCheckout.

LIGHT CIRCUIT

The light switch, supplied through an automatic resetcircuit breaker, provides 24 volts to dome lights, instru-ment panel lights, headlights and tail lights. 24 volts isalso provided to transmission range selector for illumi-nation only.

The taillights and brake lights are supplied 24 voltsthrough two resistor diodes, which allow the bulbs toilluminate at less than 24 volts.

When the service or retarder brakes are applied, a 100psi (0.7 MPa) normally open stop light pressure switchcloses, supplying 24 volts to the coil side of stop relayswitch. With the coil energized the switch side of therelay closes, and allows 24 volts to bypass the resistorsin the taillight circuit permitting the brake lights tofunction as a stop light.

The headlight dimmer switch located on the steeringcolumn will be open for low beam headlights, only twoof four bulbs are illuminated by 24 volts. Closing theheadlight dimmer switch supplies 24 volts to remainingtwo headlights. When all four lights are on, the highbeam indicator will also be illuminated. Refer to Elec-trical Schematic, Section "R".

Circuit Components

30 amp Circuit Breaker - Is mounted behind theinstrument panel beside the 30 amp manual resetbreaker. Automatic reset.

Light Switch - Is three position rocker switch mountedon the instrument panel.

Instrument Panel Light Dimmer Rheostat - Ismounted on the instrument panel. It is a variable resis-tance switch, allowing the brightness of the instrumentpanel lights to be adjusted.


Head Light Dimmer Switch - Is located in the turnsignal lever. If headlights are on low beam pulling thelever toward the steering wheel, will close headlightswitch changing low beam to high beam. Pulling thelever again opens headlights switch changing highbeam back to low beam.

Stop Light Switch - Is located in the manifold block onthe anchor structure of final drive. Normally open (N/O)switch, closes at 100 psi. (.7 MPa). The key switchsupplies 24 volts to the stoplight switch. When brakesare applied the circuit is completed through a stop lightrelay, bypassing two resistor diodes and going throughtwo diodes to the vehicles’ rear left and right tail/stoplights.

Instrument Lights - Are 24 volt bulbs inserted in backof the gauge housings. Access to bulbs is throughcover plate on front of cab below windshield, or bytilting instrument panel forward.

Head and Tail Lights - 24 volt bulbs, located on frontand rear of truck. Head lights and tail lights are supplied24 volts through a head light switch. Tail lights useresistor diodes and are grounded through the mount-ing base to complete the circuit.

Circuit Checkout

1. Voltage checks may be made at all four head light,and tail/stop lights. Connections also at back ofinstrument panel of individual components.

2. Refer to Electric Schematic, Section "R", for iden-tification of wire harness pin connections for mak-ing voltage checks at harness connections on cabfloor.

HEATER AND AIR CONDITIONERCIRCUITThe heater-air conditioner circuit is supplied with 24volts through a 30 amp circuit breaker. With the heat-airconditioner switch in "Heat" position, the fan speedswitch is supplied 24 volts, the air conditioner switch is"Open". The fan switch has three positions. Resistorsbetween switch and motor determine motor speeds.The fan motor is grounded through a diode to completethe circuit.

With heat-air conditioner switch in "Air Conditioner"position, the fan circuit is energized as well as cabthermostat, receiver dryer switch, and air conditionerclutch. Refer to Electrical Schematic, Section "R".

Circuit Components

Circuit Breaker 30 amps - Is a manual reset mountedon the instrument panel.

Heat-Air Conditioner Switch - Is located on heater-airconditioner. The switch is a three-position toggleswitch which allows the operator to choose either heat,off, or air conditioning.

Fan Switch - Is located on the heater-air conditioner.The switch provides three different fan speeds.

Fan Motor - Is located in the heater-air conditionhousing. The fan motor uses two resistors to providevariable speeds of forced air for the heating and coolingsystem.

Cab Thermostat - Is located on the heater-air condi-tioner. The thermostat allows variations of cab tem-perature to be selected by the operator.

Receiver Dryer Switch - Is a normally closed (N/C)switch located on the dryer. The dryer is mounted onthe left side of the radiator support.

Air Conditioner Clutch - Is a part of the air-conditionercompressor, which is mounted on the left front cornerof the engine. Refer to Section "M" Air ConditioningSystem for the operation of the air conditioner clutch.Also see Section "R" for Electrical Schematic".

Circuit Checkout

1. To gain access to heater-air conditioner whenmaking voltage checks at electrical components,will require tilting assembly away from side of cab.

2. Remove the left hand center deck section. Referto Section "B" Structures for removal procedure.

3. Remove the heater assembly mounting cap-screws.

4. Tilt the heater assembly away from cab.

5. Remove the access cover at rear side of heater-airconditioner.

6. Refer to the Electrical Schematic for harness con-nector pin location when making electrical checksof receiver dryer switch and air conditioning com-pressor clutch.

7. After correcting any problems, reinstall cover, andinstall heater assembly to side of the cab.

8. Install left hand center deck.


24 VDC ELECTRIC START SYSTEMThe 140M, 210M model trucks use a single crankingmotor and magnetic switch. All other models use twocranking motors and two magnetic switches. Refer topage D3-16 for schematic.

OPERATION

Heavy duty batteries supply 24VDC to each of thecranking motors through magnetic switches activatedby the key switch on the instrument panel.

When the keyswitch is placed in the ‘‘Start’’ position,the magnetic switches close, connecting the motorsolenoid ‘‘S’’ terminals to the batteries. When the sole-noid windings are energized, the plunger (56, Figure3-3) is pulled in, moving the starter drive (71) assemblyforward in the nose housing to engage the engineflywheel ring gear. Also, when the solenoid plunger ispulled in, the main solenoid contacts close to providecurrent to the motor armature and cranking takesplace. When the engine starts, an overrunning clutchin the drive assembly protects the armature from ex-cessive speed until the keyswitch is released. When thekeyswitch is released, a return spring causes the drivepinion to disengage.

After the engine is running, a normally closed pressureswitch senses engine oil pressure and opens the elec-trical circuit to prevent actuation of the motor(s) afterthe engine has started.

CRANKING MOTOR

Removal

1. Disconnect battery power using the appropriateprocedure below:

a. If truck is equipped with a battery equalizer,place the ATEC power switch in the Off posi-tion.

b. Open the battery disconnect switch to removepower from the system.

c. If not equipped with a battery disconnectswitch, remove battery cables using the follow-ing sequence if equipped with battery equal-izer:

1.) Remove the battery positive (+ ) cables first.2.) Remove the negative (-) cables last.

2. Mark wires and cables and remove from motor (1,Figure 3-1) and solenoid (3) terminals.

3. Remove motor mounting capscrews and lockwashers (2).

4. Remove motor assembly from flywheel housing.

Installation

1. Align motor (1, Figure 3-1) housing with the fly-wheel housing adaptor mounting holes and slideinto position.

2. Insert motor mounting capscrews and lock wash-ers (2).

3. Connect marked wires and cables to motor andsolenoid terminals.

4. If the truck is equipped with a battery equalizer, nobattery disconnect and the battery cables wereremoved, reinstall in the following sequence:

a. Install the negative (-) cables first.

b. Install the positive (+ ) cables.

c. Turn the ATEC switch On.

5. On other models, close battery disconnect switchor connect battery cables to the battery if notequipped with a battery disconnect switch.

FIGURE 3-1. TYPICAL STARTER INSTALLATION

1. Cranking Motor2. Capscrews & Washers

3. Solenoid


CRANKING MOTORTROUBLESHOOTINGIf the cranking system is not functioning properly,check the following to determine which part of thesystem is at fault:

Batteries-- Verify the condition of the batteries,cables, connections and charging circuit. Referto Section ‘‘D’’ for additional information.

Wiring-- Inspect all wiring for damage or looseconnections at the keyswitch, magneticswitches, solenoids and cranking motor(s).Clean, repair or tighten as required.

If the above inspection indicates the starter motor tobe the cause of the problem, remove the motor andperform the following tests prior to disassembly todetermine the condition of the motor and solenoid andrepairs required.

Preliminary Inspection

1. Check the starter to be certain the armature turnsfreely.

a. Insert a flat blade screwdriver through the open-ing in the nose housing.

b. Pry the pinion gear to be certain the armaturecan be rotated.

2. If the armature does not turn freely, the startershould be disassembled immediately.

3. If the armature can be rotated, perform the No-Load Test before disassembly.

No-Load Test

Refer to Figure 3-2 for the following test setup.

Be certain switch is open before connections ordisconnections are made during the following pro-cedures.

1. Setup the motor for test as follows:

a. Connect a voltmeter from the motor terminal tothe motor frame.

b. Use an RPM indicator to measure armaturespeed.

c. Connect a carbon pile across one battery tolimit battery voltage to 20 VDC.

Do not apply voltages in excess of 20 volts. Exces-sive voltage may cause the armature to throw wind-ings.

d. Connect the motor and an ammeter in serieswith two fully charged 12 volt batteries.

e. Connect a switch in the open position from thesolenoid battery terminal to the solenoid switchterminal.

2. Close the switch and compare the RPM, current,and voltage reading to the following specifica-tions:

• RPM: 5500 Minimum to 7500 Maximum

• AMPS: 95 Minimum to 120 Maximum

• VOLTS: 20 VDC

Interpreting Results of Tests

1. Rated current draw and no-load speed indicatesnormal condition of the cranking motor.

2. Low free speed and high current draw indicates:

a. Too much friction; tight, dirty, or worn bearings,bent armature shaft or loose pole shoes allow-ing armature to drag.

b. Shorted armature. This can be further checkedon a growler after disassembly.

c. Grounded armature or fields. Check Furtherafter disassembly.

FIGURE 3-2. NO-LOAD TEST CIRCUIT


3. Failure to operate with high current draw indicates:

a. A direct ground in the terminal or fields.

b. ‘‘Frozen’’ bearings (this should have been de-termined by turning the armature by hand).

4. Failure to operate with no current draw indicates:

a. Open field circuit. This can be checked afterdisassembly by inspecting internal connec-tions and tracing circuit with a test lamp.

b. Open armature coils. Inspect the commutatorfor badly burned bars after disassembly.

c. Broken brush springs, worn brushes, high insu-lation between the commutator bars or othercauses which would prevent good contact be-tween the brushes and commutator.

5. Low no-load speed and low current draw indi-cates:

a. High internal resistance due to poor connec-tions, defective leads, dirty commutator andcauses listed under Number 4.

6. High free speed and high current draw indicatesshorted fields. If shorted fields are suspected,replace the field coil assembly and check forimproved performance.

Disassembly

Normally the cranking motor should be disassembledonly as far as necessary to repair or replace defectiveparts.

1. Note the relative position of the solenoid (53,Figure 3-3), lever housing (78), nose housing (69),and C.E. frame (1) so the motor can be reassem-bled in the same manner.

2. Disconnect field coil connector (42) from solenoidmotor terminal, and lead from solenoid groundterminal.

3. Remove the brush inspection plates (52), andbrush lead screws(15).

4. Remove the attaching bolts (34) and separate thecommutator end frame (1) from the field frame(35).

5. Separate the nose housing (69) and field frame(35) from lever housing (78) by removing attach-ing bolts (70).

6. Remove armature (45) and drive assembly (71)from lever housing (78).

7. Separate solenoid (53) from lever housing bypulling apart.

1. C.E. Frame 2. Washers 3. O-Ring 4. Insulator 5. Support Plate 6. Brush Plate Insulator 7. Washers 8. Plate & Stud 9. Plate10. Brush Holder11. Lock Washer12. Screw13. Brush (12 req’d)14. Lock Washer15. Screw16. Brush Spring17. Screw18. Screw19. Screw20. Lock Washers21. Plate22. Brush Holder Insulator23. Screw24. Lock Washer25. Washer26. O-Ring27. Bushing28. Insulator29. Washer30. Lock Washer31. Nut32. Nut33. Lock Washer34. Screw35. Field Frame 36. Stud Terminal37. Bushing38. Gasket39. Washers40. Washer

41. Nut42. Connector43. Lock Washer44. Nut45. Armature46. Field Coil (6 Coils)47. Shoe48. Insulator49. Screw50. Washer51. O-Ring52. Inspection Plug53. Solenoid Housing54. Lock Washer55. Screw56. Plunger57. Washer58. Boot59. Washer60. Spring61. Retainer62. Snap Ring63. Shift Lever64. Nut65. O-Ring66. O-Ring67. Snap Ring68. Lever Shaft 69. Drive Housing70. Screw71. Drive Assembly72. Gasket73. Plug74. Gasket75. Brake Washer76. Screw77. Lock Washer78. Lever Housing79. Washer80. O-Ring

FIGURE 3-3 CRANKING MOTOR ASSEMBLY


FIGURE 3-3 CRANKING MOTOR ASSEMBLY


Cleaning and Inspection

1. The drive (71), armature (45) and fields (46) shouldnot be cleaned in any degreasing tank, or withgrease dissolving solvents, since these would dis-solve the lubricant in the drive and damage theinsulation in the armature and field coils.

2. All parts except the drive should be cleaned withmineral spirits and a clean cloth.

3. If the commutator is dirty, it may be cleaned withNo. 00 sandpaper.

NOTE: Never use emery cloth to clean commutator.

4. Inspect the brushes (13, Figure 3-3) for wear.

a. If worn excessively when compared with a newbrush, they should be replaced.

b. Make sure the brush holders (10) are clean andthe brushes are not binding in the holders.

c. The full brush surface should ride on the com-mutator to give proper performance. Check byhand to insure that the brush springs (16) aregiving firm contact between the brushes (13)and commutator.

d. If the springs (16) are distorted or discolored,they should be replaced.

Armature Servicing

If the armature commutator is worn, dirty, out of round,or has high insulation, the armature (45) should be puton a lathe and the commutator turned down. Theinsulation should then be undercut .031 in. (.79 mm)wide and .031 in. (.79 mm) deep, and the slots cleanedout to remove any trace of dirt or copper dust. As a finalstep in this procedure, the commutator should besanded lightly with No. 00 sandpaper to remove anyburrs left as a result of the undercutting procedure.

The armature should be checked for opens, shortcircuits and grounds as follows:

1. Opens are usually caused by excessively longcranking periods. The most likely place for anopen to occur is at the commutator riser bars.Inspect the points where the conductors arejoined to the commutator bars for loose connec-tions. Poor connections cause arcing and burningof the commutator as the cranking motor is used.If the bars are not too badly burned, repair canoften be effected by resoldering or welding theleads in the riser bars (using rosin flux), and turn-ing down the commutator in a lathe to remove theburned material. The insulation should then beundercut.

2. Short circuits in the armature are located by useof a growler. When the armature is revolved in thegrowler with a steel strip such as a hacksaw bladeheld above it, the blade will vibrate above the areaof the armature core in which the short circuit islocated. Shorts between bars are sometimes pro-duced by brush dust or copper between the bars.These shorts can be eliminated by cleaning outthe slots.

3. Grounds in the armature can be detected by theuse of a 110-volt test lamp and test points. If thelamp lights when one test point is placed on thecommutator with the other point on the core orshaft, the armature is grounded. Grounds occuras a result of insulation failure which is oftenbrought about by overheating of the crankingmotor produced by excessively long crankingperiods or by accumulation of brush dust betweenthe commutator bars and the steel commutatorring.

Field Coil Checks

The field coils (46, figure 3-3) can be checked forgrounds and opens by using a test lamp.

1. Grounds---- The ground connections must be dis-connected during this check. Connect one leadof the 110 volt test lamp to the field frame (35) andthe other lead to the field connector (42). If thelamp lights, at least one field coil is grounded andmust be repaired or replaced.

2. Opens----Connect test lamp leads to ends of fieldcoils (46). If lamp does not light, the field coils areopen.

Field Coil Removal

Field coils can be removed from the field frame assem-bly by using a pole shoe screwdriver. A pole shoespreader should also be used to prevent distortion ofthe field frame. Careful installation of the field coils isnecessary to prevent shorting or grounding of the fieldcoils as the pole shoes are tightened into place. Wherethe pole shoe has a long lip on one side and a short lipon the other, the long lip should be assembled in thedirection of armature rotation so it becomes the trailing(not leading) edge of the pole shoe.


Solenoid Checks

A basic solenoid circuit is shown in Figure 3-4. Sole-noids can be checked electrically using the followingprocedure.

Test

1. With all leads disconnected from the solenoid,make test connections as shown to the solenoid,switch terminal and to the second switch terminal‘‘G’’, to check the hold-in winding (Figure 3-5).

2. Use the carbon pile to decrease the battery voltageto 20 volts. Close the switch and read current.

a. The ammeter should read 6.8 amps maximum.

3. To check the pull-in winding, connect from thesolenoid switch terminal ‘‘S’’ to the solenoid motor‘‘M’’ or ‘‘MTR’’ terminal (Figure 3-6).

To prevent overheating, do not leave the pull-inwinding energized more than 15 seconds. Thecurrent draw will decrease as the winding tempera-ture increases.

4. Use the carbon pile to decrease the battery voltageto 5 volts. Close the switch and read current.

a. The ammeter should read 9.0 to 11.5 amps.

NOTE: High readings indicate a shorted winding. Lowreadings indicate excessive resistance.

5. To check for grounds, move battery lead from ‘‘G’’(Figure 3-5) and from ‘‘MTR’’ (Figure 3-6) to thesolenoid case. Ammeter should read zero. If not,the winding is grounded.

FIGURE 3-5. SOLENOID HOLD-IN WINDING TEST

FIGURE 3-4. SIMPLIFIED SOLENOID CIRCUIT FIGURE 3-6. SOLENOID PULL-IN WINDING TEST


Assembly

Lubricate all bearings, wicks and oil reservoirs withSAE No. 20 oil during assembly.

Bearing Replacement:

1. If any of the bronze bearings are to be replaced,dip each bearing in SAE No. 20 oil before pressinginto place.

2. Install wick, soaked in oil, prior to installing bear-ings.

3. Do not attempt to drill or ream sintered bearings.These bearings are supplied to size. If drilled orreamed, the I.D. will be too large and the bearingpores will seal over.

4. Do not cross-drill bearings. Because the bearingis so highly porous, oil from the wick touching theoutside bearing surface will bleed through andprovide adequate lubrication.

5. The middle bearing is a support bearing used toprevent armature deflection during cranking. Theclearance between this bearing and the armatureshaft is large compared to the end frame bearings.

Motor Assembly:

1. Install the end frame (with brushes) onto the fieldframe as follows:

a. Insert the armature (45, Figure 3-3) into the fieldframe (35). Pull the armature out of the fieldframe just far enough to permit the brushes tobe placed over the commutator.

b. Place the end frame (1) on the armature shaft.Slide end frame and armature into placeagainst the field frame.

c. Insert screws (34) and washers (33) and tightensecurely.

2. Assemble lever (63) into lever housing (78) Ifremoved.

3. Place washer (79) on armature shaft and installnew O-ring (80). Position drive assembly (71) inlever (63) in lever housing. Apply a light coat oflubricant (Delco Remy Part No. 1960954) onwasher(75) and install over armature shaft. Alignlever housing with field frame and slide assemblyover armature shaft. Secure with screws (76) andwashers (77).

4. Assemble and install solenoid assembly throughlever housing and attach to field frame. Install nut(64) but do not tighten at this time. Install brushinspection plugs (52).

5. Using a new gasket (72), install drive housing (69)and secure with screws (70).

6. Assemble field coil connector (42) to solenoid.

7. Adjust pinion clearance per instructions on thefollowing page.

8. After pinion clearance has been adjusted,installgasket (74) and plug(73).

Pinion Clearance

To adjust pinion clearance, follow the steps listed be-low.

1. Make connections as shown in Figure 3-7.

2. Momentarily flash a jumper lead from terminal ‘‘G’’to terminal ‘‘MTR’’. The drive will now shift intocranking position and remain so until the batteriesare disconnected.

3. Push the pinion or drive back towards the commu-tator end to eliminate slack movement.

4. The distance between the drive pinion and housingshould be between .330 in. to .390 in. (8.3 mm to9.9 mm) as shown in Figure 3-8.

5. Adjust clearance by turning shaft nut (64, Figure3-3).

FIGURE 3-7. PINION CLEARANCE CHECK CIRCUIT


Magnetic Switch

The magnetic switch is a sealed unit and not repairable.

Removal

1. Remove battery power as described in CrankingMotor ‘‘Removal’’, page D3-8.

2. Disconnect cables from the switch terminals andwires from coil terminals (Figure 3-9).

NOTE: If the magnetic switch has a diode across thecoil terminals, mark the leads prior to removal to en-sure correct polarity during installation.

3. Remove mounting capscrews and washers. Re-move switch from mounting bracket.

4. The switch coil circuit can be tested as describedbelow.

Installation

1. Attach magnetic switch to the mounting bracketusing the capscrews and lockwashers removedpreviously.

2. Inspect cables and switch terminals. Clean asrequired and install cables.

3. Install the diode across the coil terminals if re-quired. Be certain diode polarity is correct. (Referto the wiring diagram on the following page.)Attach wires from the truck harness to the coilterminals (See Figure 3-9).

4. Connect battery power as described in CrankingMotor ‘‘Installation’’, page D3-1.

Coil Test

1. Using an ohmmeter, measure the coil resistanceacross the coil terminals.

a. The coil should read approximately 28 Ω at 72°F(22.2° C).

b. If the ohmeter reads ∞, the coil is open and theswitch must be replaced.

c. If the ohmmeter reads 0 Ω, the coil is shortedand the switch must be replaced.

2. Place one of the ohmmeter probes on a coilterminal and another on the switch mountingbracket. If the meter displays any resistance read-ing, the coil is grounded and the switch must bereplaced.

3. The ohmmeter should display ∞ when the probesare placed across the switch terminals.

NOTE: The switch terminals should show continuitywhen 24 VDC is applied to the coil terminals, howeverhigh resistance across the internal switch contactsdue to arcing etc. could prevent the switch from deliv-ering adequate current to the cranking motor. If thecoil tests are satisfactory but the switch is still suspect,it should be replaced with a new part.

FIGURE 3-8. CHECKING PINION CLEARANCE

FIGURE 3-9. MAGNETIC SWITCH ASSEMBLY


ELECTRIC START SYSTEM WIRING DIAGRAMSThe following wiring diagram represent the starter system hookup for the140M and 210M model trucks. Refer to the schematics in Section ‘‘R’’ foradditional components and wiring information.


STARTER, ENGINE 24 VDC

Circuit Check-Out

1. Check that range selector is in neutral position.

2. Check that battery disconnect switch is on.

3. Check for loose starter mount capscrews, tightenif necessary. Check all wire connections and wiresin start circuit for broken wires, loose and cor-roded connections.

4. Check for 24 volts at battery cable connection onstarter motor.

If starter motor still fails to operate, proceed withfollowing steps. Refer to "ELECTRICAL SCHE-MATIC", Section "R" for 24 volt checkout.

NOTE: The following steps involve the ATEC controlcircuit. Refer to "Transmission Control Circuit", thissection, for more detail.

5. Turn keyswitch to run position. Check 5 ampcircuit breaker three (8, Figure 3-10) in relay box,reset if necessary.

6. Check for 24 volts at wire 25k to neutral relay inrelay box (15, Figure 3-10). Range selector shouldbe in neutral. If 24 volts are present at wire 25problem can be with ATEC system. Refer to ATECservice manual.

7. If steps 1-6 are satisfactory, continue with 24 voltcheckout.

a. Turn keyswitch to start position, check for 24volts wire 21 at neutral relay (15, Figure 3-10).

b. Check for 24 volts at wire 25R, start solenoid (5,Figure 3-10) in cab mounted relay box.

c. 24 volts at battery cable connection on the startsolenoid.

d. Check for 24 volts at wire 25A from start sole-noid to starter motor.

8. If steps 6 and 7 are satisfactory and starter motorwill not operate, starter motor could be defective.Remove defective component and refer to manu-facturer’s service manual for checkout and repair.

1. Auxilary Seat Support 2. Electronic Control Unit (ECU) 3. Battery Equalizer Monitor 4. Scanner Receptacle 5. Start Solenoid 6. Auto/Manual Test Switch 7. Circuit Breaker No. 4 (CB-4) 8. Circuit Breaker No. 3 (CB-3) 9. Circuit Breaker No. 2 (CB-2)10. Circuit Breaker No. 1 (CB-1)11. ATEC Test Switch12. Check Transmission Relay (CTR)13. Pressure Switch Relay (PSR)14. Switch Power Relay (SPR)15. Neutral Relay (NSR)16. Reverse Relay (RWR)17. Overspeed Relay (OR) - not used18. Hoist Relay19. Relay Box

FIGURE 3-10 CAB MOUNTED RELAY BOX


NOTES


ALLISON TRANSMISSION ELECTRONIC CONTROL (ATEC)

ATEC SYSTEM OPERATIONThe transmission in the HAULPAK® truck is controlledby the operator through a range selector located in thecab. Included is a ‘‘Do Not Shift’’ light and a ‘‘CheckTransmission’’ light to alert the operator of any potentialproblems at startup or during operation of the truck.

Range Selector

The lever-type range selector has eight positions (1, 2,3, 4, 5, D, N, & R). To change positions, release therange holding mechanism (below knob) on the lever,and move lever to the desired range.

1 - Use this gear when pulling through mud and deepsnow, or when maneuvering in tight spaces, whendriving up or down steep grades where maximumdriving power and maximum engine braking is needed.

2, 3, 4, 5 - positions. Road and load conditions some-times make it desirable to limit the automatic shiftingto a lower range. These positions provide greater en-gine braking on grades. The transmission will not shiftabove the highest gear selected. When conditionsimprove, select position "D" for full range operation.

"D" DRIVE - position. The transmission will start in firstgear and as the speed increases, the transmission willautomatically upshift through each gear to sixth gearoperation. As the truck slows down, the transmissionwill automatically downshift to the correct gear.

"N" NEUTRAL - used when truck is stopped/parkedwith engine operating, and when starting engine. The truck cannot be started unless the Range Selectoris in NEUTRAL position.

"R" REVERSE - use this position to back up the truck.Completely stop the vehicle before shifting from ‘‘For-ward’’ to ‘‘Reverse’’ or vice-versa. The Reverse WarningHorn is activated when ‘‘Reverse’’ range is selected.

‘‘DO NOT SHIFT’’ Light

The ‘‘Do Not Shift’’ lights come on anytime the on-board computer finds a potentially serious problem inthe system. The computer will cause the transmissionto lock-in-gear and also to disengage the lockupclutch. These actions by the computer reduce thepossibility of damage to the vehicle and transmission.The hold-in-range feature prevents upshifts and down-shifts when a problem is detected in the operation ofthe transmission. The hold-in-gear circuit permits thetransmission to continue to operate in the gear it wasin at the time the ‘‘Do Not Shift’’ light and buzzer turned

‘‘On’’. Selection of a different gear range will have noeffect on the transmission. The hold-in-gear circuit isreleased when the engine is shut-off. If the problemcausing the ‘‘Do Not Shift’’ light is still present when theengine is restarted, the transmission will be shifted to‘‘Neutral’’ and will remain in ‘‘Neutral’’ until the problemis corrected.

RESET PROCEDURE: When the ‘‘Do Not Shift’’ lightand/or ‘‘Check Trans’’ lights come ‘‘On’’, the systemcan be cleared or reset. To reset, bring the vehicle toa stop at a safe location and shut down the engine. Waitabout 10 seconds and restart engine. If the problem istemporary, the ‘‘Do Not Shift’’ and ‘‘Check Trans’’ lightswill not come back ‘‘On’’ and the truck can be operatedin a normal manner.

‘‘CHECK TRANS’’ Light

The ATEC system has a built in computer that monitorsvarious functions and performances. The ‘‘CheckTrans’’ light will come ‘‘On’’ when the ignition is turned‘‘On’’. After the engine is started, the engine oil pressureswitch closes and the light will go ‘‘Off’’. This providesa light bulb check and a system check. When thecomputer senses that the system is not performingproperly, the ‘‘Check Trans’’ light comes ‘‘On’’ to warnand alert the operator that a problem has occurred.Bring the truck to a safe stop, apply the parking brakewhen the light comes "ON" place the ATEC test switch(11, Figure 4-7) in the test position and read the blinkinglight error code. Refer to Allison "Off-Highway ATECTroubleshooting Manual" for a description of the errorcode meanings (refer to Figure 4-8). The vehicle shouldbe serviced as soon as possible.

FIGURE 4-1. RANGE SELECTOR

D04003 8/95 Allison Transmission Electronic Control (ATEC) D4-1

In cold weather, when the temperature of the transmis-sion oil is below -10°F (-23°C), the ‘‘Do Not Shift’’ lighton the Range Selector and the ‘‘Check Trans’’ light willstay ‘‘On’’ after the engine is started. The transmissionwill stay in ‘‘Neutral’’, regardless of which range isselected until the oil is warmer than -10°F (-23°C). Whenthe transmission oil warms up, the ‘‘Check Trans’’ and‘‘Do Not Shift’’ lights will turn ‘‘Off’’ and the transmissionwill operate in first gear or reverse only. At 20°F (- 7°C),the transmission may be operated safely in all ranges.

If the transmission oil temperature reaches 250°F(121°C), the ‘‘Check Trans’’ indicator light will come‘‘On’’. The ECU (Electronic Control Unit) will inhibitoperation of the truck above 4th range.

NOTE: The Transmission Temperature Gauge on theinstrument panel indicates the temperature of oil com-ing out of the converter. The ECU senses oil tempera-ture in the sump.

SYSTEM DESCRIPTION

The HAULPAK® truck utilizes the Allison TransmissionElectronic Control (ATEC) for automatic control of thetransmission functions.

The ATEC system consists of an Electronic ControlUnit (ECU), a Throttle Position Sensor (TPS), an OutputShaft Speed Sensor, a Range Selector, eight (8) sole-noids, a body up switch, maintenance/test block, achassis harness and a cab harness.

The ECU (Figure 4-3) receives input signals from vari-ous components of the ATEC system and causesautomatic up and down shifting of the transmissionafter the operator has made a range selection with thelever of the range selector.

The TPS (Figure 4-4) provides a signal to the ECU withregards to the position of the operator’s throttle pedal.

The output shaft speed sensor provides an AC voltagesignal at a frequency (HZ) proportional to the truck’srear wheel speed. The range selector provides thedesired range.

The ECU utilizes these inputs to determine the properoperating mode related to the transmission system andprovides numerous output signals to control the trans-mission clutches, range selected/range attained dis-play (if equipped), neutral start circuit, backup lightcircuit, system malfunction lights, speedometer circuit,optional overspeed warning circuit and malfunctioncode.

The chassis harness interconnects the ECU with theTPS, output shaft speed sensor, main clutch controlvalve body and the lockup valve body. The cab harnessinterconnects the ECU with the Range Selector, diag-nostic scanner, and the numerous switches and relays.

SUMP OIL TEM-PERATURE

‘‘DO NOTSHIFT’’LIGHT

‘‘CHECK TRANS’’LIGHT

TRUCKOPERATION

-10° F(-24° C)AND BELOW

ON ON NEUTRALONLY

-9° F(-22° C) TO+ 19° F(-7° C)

OFF OFF NEUTRAL,FIRST &

REVERSEONLY

+ 20° F(-7°)AND ABOVE

OFF OFF FULL OPERATION

In All Ranges

FIGURE 4-2. OIL TEMPERATURE CHART

FIGURE 4-3. ELECTRONIC CONTROL UNIT (ECU)

FIGURE 4-4. THROTTLE POSITION SENSOR (TPS)

D4-2 Allison Transmission Electronic Control (ATEC) D04003 8/95

Refer to Figure 4-6 for a diagram describing the hookupof the various components.

The ATEC system operates primarily on 12VDC and isinterfaced with many of the HAULPAK® truck circuits.Therefore, a Battery Equalizer (Figure 4-5) is providedto maintain equal charge on both truck batteries. Theexternal 24VDC. functions of the truck related to thetransmission system are controlled by relays which arecontrolled by the ECU or range selector. The ECU alsomonitors the system for abnormal fault conditions.When such a fault condition is detected, the ECUautomatically responds in a manner which is safe forthe operator, the truck, and the transmission. It alsorecords an appropriate malfunction code in its mem-ory. When the abnormal condition occurs, the ‘‘CheckTransmission’’ light is turned on. Additionally, withsome conditions, the ‘‘Do Not Shift’’ light and a buzzeris activated in the Range Selector alerting the operatorto the potential problem.

Before welding on truck, be sure alternator andbattery equalizer are completely disconnected.Remove equalizer ground first, then disconnect 12and 24 volt positive terminals. When connectingback in system, connect 24 and 12 volt positiveterminals first, ground terminal last. When disconnecting the truck batteries, the follow-ing procedure MUST be followed in the sequenceshown to prevent damage to the ATEC systemcomponents:

1. Turn ATEC power switch ‘‘OFF’’.

2. Remove the battery 12V positive (+ ) terminal. DO NOT LET TERMINAL TOUCH CHASSISGROUND!

3. Remove the battery 24V positive (+ ) terminal.

4. Remove the battery 24V negative (-) terminal.

5. Disconnect harness connectors at the ECU afterdisconnecting battery power.

6. Cover ATEC components and wiring to protectfrom hot sparks, etc. Do not connect weldingcables to ATEC components. Do not weld onATEC components. Remove ATEC componentsif welding within 10 in. (25 cm) of component.

7. When reconnecting components, reverse the or-der of steps 1 through 6. Check wiring and cablesfor proper routing and termination.

TRANSMISSION CONTROL CIRCUITS

The following circuits can be affected by a problem ineither the HAULPAK® electric or the ATEC circuit:engine starting, ATEC control power, backup horn andlights, speedometer, hoist interlock and a portion ofATEC warning system.

Refer to Electrical Schematic, Section ‘‘R’’ to determineif the problem is with the HAULPAK® or ATEC circuit.For example; the engine will not crank. If the problemis in the ATEC circuit, the ‘‘Off-Highway ATEC Trou-bleshooting Manual’’ should be used to determinecomponent causing problem.

Battery Charging Circuit

Two 12 volt batteries connected in series, supply 24volts to the system. The batteries are recharged froman engine driven alternator with built-in voltage regula-tor. The voltmeter indicates the output voltage of thebattery charging alternator. Normal indicated voltageat high idle is 27 -- 28 volts. When the key switch is ‘‘On’’and engine is not running, the voltmeter indicatesbattery voltage.

One 12 volt battery supplies the transmission controlcircuit. To prevent unequal charge and discharge of thebatteries, a battery equalizer is provided in the chargecircuit. The battery equalizer balances charge anddischarge of both batteries. Refer to Electrical Sche-matic in Section ‘‘R’’.

The equalizer is equipped with a circuit breaker forinternal protection. If the breaker is activated, it mustbe reset to prevent one battery running down. The faultcausing the breaker to activate must be corrected also.

FIGURE 4-5. BATTERY EQUALIZER


FIGURE 4-6. ATEC SYSTEM DIAGRAM


Control Power and Memory Circuits

One battery supplies the switch side of two normallyopen (N/O) relays with 12 volts. This signal is alsocontinuously supplied to the ATEC Electronic ControlUnit (ECU) for memory power. When keyswitch is in‘‘Start’’ or ‘‘Run’’ position, the coil side of the SwitchPower Relay is supplied with 24 volts. The relay closessupplying 12 volts to the ECU and range selector.When engine is started, engine oil pressure closes anormally open (N/O) pressure switch supplying 24volts to the oil Pressure Switch Relay (PSR) coil. Therelay closes supplying the ECU with 12 volts. Thiscontrol circuit configuration maintains power to ATECif the keyswitch should be turned ‘‘Off’’ during truckoperation.

Start Circuit

When the keyswitch is moved to ‘‘Start’’ position, aNeutral Relay coil will be energized through a 5 ampcircuit breaker. The ground will be completed for therelay coil when the transmission shift selector is in the‘‘Neutral’’ position. When neutral relay (NSR) closes,the coil of the start solenoid is energized, providingpower to the starter for cranking the engine.

Check Transmission Warning Light Circuit

When the keyswitch is in ‘‘Run’’ position, the ‘‘CheckTransmission’’ light will be grounded through normallyclosed (N/C) switch side of Check Transmission relay(CTR). When the engine is started or running, engineoil pressure closes the normally open (N/O) oil pres-sure switch supplying 24 volts to the coil side of theCheck Transmission Relay (CTR). When the coil isgrounded through the ECU, the relay opens turning‘‘Off’’ the ‘‘Check Transmission’’ light. If during opera-tion the ECU detects a fault condition, the relay coilground will open, turning ‘‘On’’ the ‘‘Check Transmis-sion’’ light.

When the ‘‘Check Transmission’’ light comes ‘‘On’’,activating the normally open (N/O) test switch willcause the ‘‘Check Transmission’’ light to flash a faultcondition code. Refer to Allison ‘‘Off-Highway ATECTroubleshooting Manual’’ for a description of the codemeaning.

Backup Horn and Light Circuit

The backup horn and lights are supplied with 24 voltsby a normally open (N/O) relay. The coil side of ‘‘Re-verse’’ relay (RWR) is supplied with 24 volts from thekeyswitch. The ground for the coil is provided by theECU. When the range selector is moved to ‘‘Reverse’’position, ECU completes the ground of Reverse Relay(RWR) coil, relay closes supplying backup horn andlights with 24 volts.

Hoist Interlock Circuit

This circuit prevents the truck from moving backwardsif shift selector is in ‘‘Reverse’’ position and body hoistcircuit is actuated. A circuit is completed through anormally closed (N/C) hoist pressure switch for ‘‘Re-verse’’ range to be applied. The hoist interlock pressureswitch is opened when the hoist control lever is in the‘‘Power Up’’ position. If the range selector is in ‘‘Re-verse’’, the transmission will be shifted to ‘‘Neutral’’ bythe ECU. If selector is in ‘‘Neutral’’ and is moved to‘‘Reverse’’, shift will not occur. When the hoist controllever is released and the range selector was in ‘‘Re-verse’’, the range selector must be moved to ‘‘Neutral’’and back to ‘‘Reverse’’ for shift to occur. All forwardshifts will occur even if the hoist switch is actuated.

Auto/Manual Circuit

In normal operation, shifts are made automatically, butsituations occur that require manual shifts be made,such as making engine stall speed check. A toggleswitch is available in the ATEC system to allow manualshifts to occur for maintenance reasons. For normaloperation, the toggle switch is left open to provideautomatic shifts. With toggle switch in closed or ‘‘Man-ual’’ position, transmission will shift to range selectedby lever.

Overspeed Relay Circuit (Not Used)

The coil side of the overspeed relay is supplied with 24volts and grounded by ECU. The normally open (N/O)switch side of the overspeed relay (OR) is supplied with24 volts, but the output is not connected. This relay isnot used in the current HAULPAK® truck.

Speedometer Circuit

The speedometer is supplied with 24 volts from thekeyswitch and is grounded to the system. A signaloriginating at the magnetic pickup is supplied to theECU. The ECU provides a signal to the gauge whichprovides a MPH or KPH reading on the speedometer.


TRANSMISSION CIRCUITCOMPONENTS

Keyswitch - is mounted in instrument panel and com-pletes the ‘‘Start Circuit’’ when moved to ‘‘Start’’ posi-tion and the transmission range selector is in the N,‘‘Neutral’’ position.

1. Auxilary Seat Support (refer to Figure 4-7) - Theauxiliary seat is located behind the operator seatand contains the following components:

2. Electronic Control Unit (ECU) - processes inputsignals from the various components to controlthe operation of the transmission.

3. Battery Equalizer Monitor - Monitors the batteryequalizer for correct charge and discharge of thebatteries.

4. Scanner Receptacle - Provides connection for aDisplay Data Line scanner (DDL) for use in trou-bleshooting the ATEC system.

5. Start Solenoid - The start solenoid is normallyopen (N/O) with 24 volts to coil and 24 volts toswitch side.

6. Auto/Manual Test Switch - Located in relay boxfor diagnostic test work and engine stall tests;requires knowledge of transmission electrical wir-ing.

Circuit Breakers (7 - 10) - four manual reset circuitbreakers are provided for the protection of thevarious ATEC relay switches:

7. Circuit Breaker No. 4 (CB-4)- 5 amp - Keyswitchsupplies 24 volts through wire 25f to BatteryEqualizer Monitor and normally (N/O) switch sideof overspeed relay.

8. Circuit Breaker No. 3 (CB-3) - 5 amp - Keyswitchsupplies 24 volts to coil side of neutral, reverse,and overspeed relays. Also wire 235/pin2A.

9. Circuit Breaker No. 2 (CB-2) - 5 amp - Withengine running, alternator supplies 24 volts toengine oil pressure switch, coil side of oil pressureindicator relay, pressure switch relay, and CHECKTRANS relay; also to wire 215/pin 3h.

10. Circuit Breaker No. 1 (CB-1) - 10 amp - Supplied12 volts from 12 volt side of Battery Equalizer tonormally open (N/O) switch side of PressureSwitch and Switch Power Relays also wire 203/pin3A.

11. ATEC Test Switch - The test switch is a toggleswitch located on the relay box. It is used in locat-ing and clearing diagnostic codes in the ATECsystem.

12. Check Transmission Relay (CTR) - normallyclosed (N/C), with 24 volts to coil side, and 24 voltsto switch side; provides a ground for CHECKTRANS light.

13. Pressure Switch Relay (PSR) - normally open(N/O), with 24 volts to coil side, and 12 volts toswitch side.

14. Switch Power Relay (SPR) - normally open (N/O),with 24 volts to coil side, and 12 volts to switchside.

15. Neutral Relay (NSR) - normally open (N/O), with24 volts to coil side, and 24 volts to switch side.Refer to ‘‘Backup Horn and Light Circuit’’.

16. Reverse Relay (RWR) - normally open (N/O), with24 volts to coil side, and 24 volts to switch side.

17. Overspeed Relay (OR) - not used

18. Hoist Relay - normally closed (N/C), with 24 voltsto coil side, and 12 volts to switch side.

19. Relay Box contains ATEC components indicated.

FIGURE 4-7. CAB MOUNTED RELAY BOX


CIRCUIT DESCRIPTION AND CHECKOUT

The following procedure is designed to aid in the un-derstanding of the ATEC electrical schematic. Theprocedure also contains circuit checkouts which aid inisolating problems between the HAULPAK® truck cir-cuit and the ATEC circuit. Refer to Electrical Schematic,Section ‘‘R’’, when performing circuit voltage and con-tinuity checks.

Improper use of the Maintenance/Test Terminalscan cause damage to the drive train. Specificknowledge of the complete ATEC system is re-quired for these diagnostic checks.

1. Electric power (12 volts) is supplied to the ATECsystem wires (202A) & (233A) through two relays:one controlled by the key switch and one control-led by engine oil pressure. If the engine will notcrank:

a. Place transmission range selector in ‘‘Neutral’’position.

b. Battery disconnect (if equipped) must beclosed.

c. Move key switch to "Start" position. With a VOM,make following voltage checks:

1). 24 volts at the starter solenoid; wire (25R).2). 24 volts at the neutral start relay; wire (25R).3). 24 volts at the neutral start relay; wire (21).4). If voltage readings are not acceptable, cor-

rect the cause before proceeding.

d. Remove wire (25R) from start solenoid.1). Connect a VOM from terminal (25R) of start

solenoid to ground.2). Move keyswitch to ‘‘Start’’ position.3). If VOM indicates 24 volts, the HAULPAK® and

ATEC circuit are correct. Begin voltagechecks with the electric starter, check wiringfrom start solenoid to starter wire (25A). Re-fer to manufacturer’s Service Manual forelectric starter checkout.

4). If VOM does not indicate 24 volts at (25R) ofstart solenoid, proceed to the followingsteps:

e. Connect a VOM at terminal 25C of terminal stripin relay box. Move key switch to ‘‘Start’’ posi-tion.

1). If a reading of 12 volts at 25C is not found,correct HAULPAK® circuit problem.

2). If a reading of 12 volts at 25C is present,proceed to following steps:

f. Connect a jumper from terminal 25, to theground terminal on relay box.

1). Move keyswitch to ‘‘Start’’ position, if VOMdoes not read 24 volts at 25A of start sole-noid, correct HAULPAK® circuit problem.

2). If a reading of 24 volt at wire (25A) of startsolenoid is obtained, check ATEC circuit.Refer to ‘‘ATEC Off-Highway Troubleshoot-ing Manual’’.

g. Reconnect wire (25R) to start solenoid.

2. 12 V.D.C. is also supplied directly to the ECU wire(203) to provide for the continuous memory of anymalfunction codes and TPS calibration values.Maximum current draw is 10 Ma and will notappreciably drain the batteries.

3. A battery ground is provided to the ECU wires(208), (209) and the Range Selector wire (234).Power for the illumination of Range Selector lightsis supplied to wire (230) through the instrumentpanel dimmer rheostat.

4. When the ECU detects an abnormal condition, itturns ‘‘On’’ the ‘‘Check Transmission’’ light andrecords the malfunction code. If the malfunctionis serious, the ECU turns ‘‘On’’ the ‘‘Do Not Shift’’lights and prevents further shifting of the transmis-sion. The transmission remains in the gear it wasin at the time of the malfunction.

Turning ‘‘On’’ the ATEC Diagnostic Switch groundswire (216) causing the ECU to turn the ‘‘CheckTransmission’’ light ‘‘On’’ and ‘‘Off’’ indicating amalfunction code stored in the memory of the ECUidentifying the location of the malfunction.

a. To clear the ECU memory of codes after thefault condition has been corrected:

1). Shut down the engine.2). Turn keyswitch ‘‘Off’’ then ‘‘On’’.3). Turn the Test Transmission Switch ‘‘On’’.4). Move Range Selector to ‘‘Reverse’’ and hold

for several seconds. 5). Move Range Selector to ‘‘Neutral’’.

b. To check for proper operation of the CheckTransmission Test Switch:


1). Turn keyswitch to ‘‘Run’’ position. Move testswitch to ‘‘Test’’ position; switch should beclosed.

2). Check transmission light will flash ‘‘On’’ and‘‘Off’’.

3). If light does not flash, make sure switch isclosed when in the ‘‘Test’’ position If switchis not closed, correct problem.

4). If switch does close in ‘‘Test’’ position andlight does not flash, refer to ‘‘ATEC Off-High-way Troubleshooting Manual’’.

5. The ‘‘Check Transmission’’ light is controlled by arelay wire (215) that will energize only when theengine is running, the oil pressure switch isclosed, and the ECU detects a malfunction in theATEC system.

a. If ‘‘Check Transmission’’ light does not turn‘‘On’’:

1). Check bulb. 2). Check that switch side of ‘‘Check Transmis-

sion’’ Relay is closed.

b. Light does not go out after engine starts:1). Check for 24 volts at terminal 25B on terminal

strip in relay box. 2). If 24 volts are not present,

correct HAULPAK® circuit.3). If 24 volts are present and light does not go

out, connect a jumper from 25B to ground.4). If light does not go out, correct HAULPAK®

circuit problem.5). If light goes out, refer to ‘‘ATEC Off-Highway

Troubleshooting Manual’’.

6. The neutral start circuit is controlled by a relay wire(231) that is energized only when the Range Se-lector is positioned in ‘‘Neutral’’. A Park BrakePressure Switch is also connected to this ‘‘Neu-tral’’ circuit, preventing the transmission from be-ing shifted into ‘‘Forward’’ or ‘‘Reverse’’ range aslong as the Park Brake is applied.

7. Wire (222) is connected to wire (309). This circuitis used in conjunction with the parking brake.When the circuit is opened, the transmission willnot shift into ‘‘Forward’’ or ‘‘Reverse’’.

The backup lights and horn are controlled by arelay wire (214) which is grounded by the ECUwhen the transmission is in ‘‘Reverse’’.

a. If the backup horn and lights do not turn ‘‘On’’when shift selector is in ‘‘Reverse:’’

1). Shut down engine, turn keyswitch to ‘‘Run’’position.

2). Connect a jumper from terminal 25E on theterminal strip in relay box to a ground.

3). If horn and lights do not operate, correctHAULPAK® circuit problem.

4). If horn and lights operate, refer to ‘‘ATECOff-Highway Troubleshooting Manual’’.

b. Backup horn and lights will not turn ‘‘Off’’ whenshift selector is moved to ‘‘Neutral’’ or ‘‘For-ward’’ range.

1). If horn and light are ‘‘On’’, with keyswitch"Off",correct HAULPAK® circuit problem.

2). If horn and lights are ‘‘On’’, with keyswitch‘‘On’’, disconnect and isolate wires from ter-minal 25E of the relay box terminal strip. If horn and lights turn ‘‘Off’’, refer to ‘‘ATECOff-Highway Troubleshooting Manual’’.

8. An optional function is available that can be acti-vated if the ECU senses an overspeed of the drivetrain. This function is controlled by a relay wire(213).

9.The ECU utilizes the output speed sensor to pro-vide a signal to the speedometer wire (205) indi-cating the speed of the truck.

a. If the speedometer is not functioning:1). With engine shutdown, place keyswitch in the

‘‘Run’’ position.2). Check for a 24 volt reading at "B" terminal on

the back side of speedometer. If no readingis indicated, refer to Section ‘‘R", ElectricalSchematic, when performing circuit voltageand continuity checks.

3). If 24 volts is present, refer to ‘‘ATEC Off-High-way Troubleshooting Manual’’ for outputspeed sensor adjustment.

NOTE: Initial adjustment for output speedsensor is:screw sensor all the way in to justtouch the center of a gear tooth and then turnout (counterclockwise) 3/4 turn.

10. Hoist Interlock wire (309) is a logic return circuit forthe ECU. The hoist relay controlled by the hoistcontrol lever opens wire (305) to wire (309) whenthe body is being raised, which immediately tellsthe ECU to shift the transmission to ‘‘Neutral’’ if itis in ‘‘Reverse’’. While the hoist lever is in the ‘‘BodyUp’’ position, ‘‘Reverse’’ cannot be obtained. ‘‘Re-verse’’ can be obtained only by having the RangeSelector in ‘‘Neutral’’ after the hoist lever is re-leased from the ‘‘Body Up’’ position.


The purpose of this feature is to prevent accidentalrearward movement of the truck when the operatorbegins to raise the body. There is no body interlockfunction to inhibit ‘‘Forward’’ operation.

a. If the truck moves in reverse when the hoistcontrol lever is held in ‘‘Power Up’’ position:

1). Shut down engine and turn key switch ‘‘Off’’.2). Remove ATEC plug J3 from ECU.3). Connect an ohmmeter between pin J and E

of the J3 harness.4). Ohmmeter should indicate continuity

through relay of hoist interlock circuit.5). Turn keyswitch ‘‘On’’, move hoist control

lever to ‘‘Power Up’’ position. Ohmmetershould indicate infinity.

6). If ohmmeter does not indicate hoist relayopening when hoist control lever is moved to‘‘Power Up’’ position, repair wiring to relay orreplace relay.

7). If ohmmeter indicates hoist relay opens whenhoist switch is moved to ‘‘Power Up’’ posi-tion, refer to ‘‘ATEC Off-Highway Trou-bleshooting Manual’’.

8). Install J3 plug into ECU.

b. Transmission will not shift to ‘‘Reverse’’ rangewhen range selector is moved to ‘‘Reverse’’position.

1). Turn keyswitch ‘‘Off’’.2). Remove J3 plug from ECU.3). Check for continuity between pins J and E of

J3 harness plug with an ohmmeter.4). If ohmmeter reads infinity, correct circuit

problem in HAULPAK® wiring.5). If ohmmeter indicates continuity, refer to

‘‘ATEC Off-Highway Troubleshooting Man-ual’’.

11. The Battery Equalizer is connected from the batter-ies to the ATEC battery disconnct (on left side ofengine) and to the 24 volt terminal on the BatteryEqualizer by wire (2T). The 12V terminal is con-nected to the ECU by going through CB-1 usingwire (1T). Wire (1T) is also connected to one of thetwo batteries through the ATEC battery discon-nect.

Before welding on truck, be sure alternator andbattery equalizer are completely disconnected.Remove equalizer ground first, then disconnect 12and 24 volt positive terminals. When connectingback in system, connect 24 and 12 volt positiveterminals first, ground terminal last.

12. If the battery equalizer is not functioning properly:

a. Check circuit breaker; if the button is out, resetby depressing button.

b. Check each battery for a 12 volt full chargecondition.

NOTE: Replace batteries in PAIRS only - otherwiseEqualizer and ATEC problems are sure to exist!

c. Check voltage between 12 volt and 24 voltterminals with a voltmeter and record the read-ing.

d. Check voltage between 12 volt terminal andground terminal and record the reading.

e. If difference between the two voltage readingsis more than 0.75 volts, replace equalizer. Referto Electrical Schematic, Section ‘‘R’’.

NOTE: Transmission shift problems, as well as reducedBattery Equalizer life may be experienced if external 12volt devices are connected to the 12 volt power supplyfor the ATEC system. If such devices are to be used, itis highly recommended the power supply is taken fromthe 24 volt system and converted to isolate the ATECsupply as much as possible.


OFF - HIGHWAY HAULING

TRANSMISSIONS ATEC DIAGNOSTIC CODES

13 - LOW BATTERY VOLTAGE

21 - THROTTLE SENSOR

22 - SPEED SENSOR

23 - PRIMARY RANGE SELECTOR

24 - OIL TEMPERATURE

33 - OIL TEMPERATURE SENSOR

34 - PROM CHECK

41 - A SOLENOID / CIRCUITRY

42 - B SOLENOID / CIRCUITRY

43 - C SOLENOID / CIRCUITRY

44 - D SOLENOID / CIRCUITRY

45 - E SOLENOID / CIRCUITRY

51 - K (LOCKUP) SOLENOID / CIRCUITRY

54 - SOLENOID CHAIN (A-E)

61 - G (SPLITER OVERDRIVE) SOLENOID / CIRCUITRY

62 - F (SPLITTER DIRECT) SOLENOID / CIRCUITRY

63 - G (SPLITTER OVERDRIVE) SOLENOID / CIRCUITRY

69 - ELECRONIC CONTROL UNIT ERROR

Range SolenoidsEnergized

ClutchesEngaged

1 C, F Splitter-Direct, Low

2 C, G Splitter-Overdrive, Low

3 D, F Splitter-Direct, Intermediate

4 D, G Splitter-Overdrive, Intermediate

5 E, F Splitter-Direct, High

6 E, G Splitter-Overdrive, High

N A, F Splitter-Direct

R A, B, F Splitter-Direct,Reverse

FIGURE 4-8. ATEC DIAGNOSIC CODES


SECTION F

TRANSMISSION AND PTO

INDEX

TRANSMISSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-1Transmission Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-1Transmission Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-2Transmission Fill Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-3

TRANSMISSION FILTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-4Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F2-4

TRANSMISSION OIL COOLER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-1Removal and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-1Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F3-1

POWER TAKE OFF (PTO) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F4-1 PTO GEARBOX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F4-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F4-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F4-1Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F4-2Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F4-3

DRIVELINES & U-JOINTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-1Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-1Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F5-2

F01003 5/92 Index F1-1

NOTES

F1-2 Index F01003 5/92

TRANSMISSIONThe HAULKPAK® Truck utilizes a remote mountedAllison CLT-6062 transmission equipped with a TC683Torque Converter. It is a fully automatic shift transmis-sion equipped with Allison Transmission ElectronicControl (ATEC). The transmission has six speeds "For-ward" and one "Reverse".

The transmission has a gear driven, side-mountedPower Take-Off assembly that drives both the steeringand hoist pumps. When removing the transmission itis advised that unless the Power Take-Off needs repair,it be disconnected from the transmission with thepumps in place.

Transmission Removal

1. Park truck on a level surface, block wheels andapply park brake. Raise dump body and installbody holding pins. Move hoist valve to "Float"position to put weight of dump body on pins.

NOTE: If hydraulic pump or engine is inoperative,dump body should be raised with a crane so bodyholding pins can be installed.

2. Turn keyswitch "Off" and shut down engine. Wait90 seconds for steering accumulator to bleeddown. Rotate steering wheel back and forth; nomovement should occur.

3. Remove transmission guard, if equipped. Placeclean container [transmission holds approxi-mately 20 gal. (76 l)] under transmission. Removedrain plug on bottom of transmission and drain oilbefore transmission removal.

The Power Take-Off and hydraulic pump assemblymust be supported by a sling or bracket from theright frame rail when disconnected from the trans-mission.

4. Remove and cap lubrication line from PTO. Re-move the four capscrews (1, Figure 2-1) and fourhex nuts (3) securing the Power Take-Off to thetransmission. While supporting the weight of thePower Take-Off and hydraulic pumps, slide theassembly away from the transmission until thePTO gear is disengaged from the transmission.

NOTE: If the PTO needs repair, refer to the PowerTake-Off disassembly procedure later in this Section.

5. Remove three electrical cable connections (1,Figure 2-2) from right side of transmission.

6. Tag and disconnect wires from two filter indicatorswitches, pressure sender (right front), tempera-ture sender (left front).

7. Remove front and rear drive shaft protectors tofacilitate transmission removal.

8. Disconnect drive shafts from front and rear oftransmission. Tie drive shafts out of the way toprevent interference during transmission removal.

FIGURE 2-1. P.T.O. AND PUMP ASSEMBLY

1. Capscrews 3. Nuts 2. Mount Shims

FIGURE 2-2. ELECTRICAL CONNECTIONS

1. Transmission Electrical Harness

F02003 5/92 Transmission F2-1

9. Tag, disconnect and cap return oil line (1, Figure2-3) from left front side of transmission. Discon-nect and cap outlet line (3) from left side oil filterassembly.

NOTE: Filter assembly (2) and lines will contain oil.Have a suitable container available to catch oil in lines.Before transmission removal, remove left side oil filterhousing (3) and drain oil from container.

10. Remove and cap hydraulic line from parking brakeactuator.

11. Remove and cap transmission oil fill hose at rearof transmission. Insure all hydraulic lines are se-cured out of the way to prevent interference duringtransmission removal.

12. Attach an appropriate lifting device to top of trans-mission and take up slack. Transmission weighsapproximately 2,500 lbs. (1135 kg).

13. Remove six capscrews, locknuts, and washers (5,Figure 2-4) securing transmission trunnions toframe rails.

14. Lift transmission assembly slowly. During transmis-sion removal, the transmission will have to bemoved around exhaust pipes carefully to preventdamage.

15. Move transmission to a clean work area for furtherdisassembly or repair. Refer to the Allison Trans-mission Service Manual for "Repair and Service"information.

NOTE: If internal malfunctions have occurred in thetransmission, the heat exchanger, both filter assem-blies and cooler lines should be thoroughly flushedand cleaned to prevent any possibility of contamina-tion when transmission is reinstalled.

Transmission Installation

1. Check all rubber vibration dampeners (1, Figure2-4) for wear, damage or deterioration. Replaceany dampeners in doubtful condition.

2. Dump body must be up and safety pins in place.DO NOT work under raised dump body unless thebody pins are installed.

3. Install rear mounting brackets (2, Figure 2-4) ontransmission and secure each with four cap-screws and lockwashers (3). Tighten to 125 ft.lbs.(170 N.m) torque.

4. If transmission front trunnion (4) was removed,thoroughly inspect bushing for wear or damage.If the trunnion bushing was removed, clean bush-ing mounting surface of trunnion thoroughly.

5. Press a new bushing into trunnion bore carefully.Bushing flange must be facing transmission wheninstalled.

6. Attach spreader bar or lifting device to transmis-sion so it will balance evenly when lifted into thetruck. Transmission weighs approximately 2,500lbs. (1135 kg).

7. Lift transmission into position between the truckframe rails. Use caution when positioning trans-mission around exhaust pipes.

FIGURE 2-3. TRANSMISSION COOLANT LINES AND FILTER ASSEMBLY

1. Oil Return 3. Outlet (to Cooler) (from Cooler) 2. Filter Assembly

FIGURE 2-4. TRANSMISSION MOUNTING

1. Vibration Dampeners 4. Front Trunnion 2. Rear Mounting Bracket 5. Capscrews, Locknuts,3. Capscrews and and Washers Lockwashers

F2-2 Transmission F02003 5/92

8. Align mounting brackets with vibration dampeners(both front and rear). Insert six capscrews (5,Figure 2-4) through the mounting brackets andvibration dampeners. Carefully lower transmis-sion onto vibration dampeners.

9. Install lower vibration dampeners.

10. Install one large flat washer (1, Figure 2-5) and selflocking nut (2) on each mounting capscrew (3).Evenly tighten capscrews and locking nuts untilvibration dampeners have been compressed to aheight of 1.31 in. (33.3 mm). Refer to Figure 2-5.

11. Refer to the PTO Installation procedure and installthe PTO and hydraulic pump assembly.

12. Position drive shafts and connect to transmission.Tighten front capscrews with locknuts to 100 ± 5ft. lbs. (136 ± 7 N.m) torque. Tighten rear driveshaft capscrews to 100 ± 5 ft. lbs. (136 ± 7 N.m)torque.

13. Connect oil return line (1, Figure 2-3) and oil outletline (3) to transmission filter assembly (2). Use newO-rings in these connections where applicable.

14. Thoroughly clean filter canisters and install newfilter elements in both filter assemblies.

15. Connect transmission oil fill hose at rear of trans-mission. Tighten fitting securely.

16. Install electrical control cables (1, Figure 2-2) onright side of transmission.

17. Install electrical wires to filter indicator switches,pressure sender, and temperature sender.

18. Install drive shaft protectors around input andoutput shafts. Tighten capscrews to standardtorque.

19. Insure all connections have been properly madebefore servicing transmission.

Transmission Fill Instructions

NOTE: If filling is required, use clean Type C-4 oil only.

1. Check transmission oil level with truck parked onlevel surface, block wheels and apply parkingbrake. Refer to Section "P", Lubrication and Serv-ice, for oil specifications. Transmission holds ap-proximately 20 gal. (76 l).

2. Start the engine and allow transmission oil to fillfilters, lines and oil cooler. Allow engine to run atapproximately 1000 RPM until transmission oilreaches operating temperature, and transmissionin neutral.

3. With engine running at "Low Idle", remove oil "Full"plug on back of transmission or view sight glasson left side of transmission to determine properoil level. Oil level should be not more than half fullin sight glass or just trickle from top ("Full") pet-cock (or should be just below the FULL mark. Ifadditional oil is needed, remove transmission fillcap located on the left side of the hydraulic tank,fill with Type C-4 to proper level . DO NOT OVER-FILL.

4. Remove blocks from wheels if truck is to beoperated.

FIGURE 2-5. TRANSMISSION VIBRATION DAMPENERS

1. Flat Washer 2. Self-locking Nut 3. Capscrew

F02003 5/92 Transmission F2-3

TRANSMISSION FILTERThe transmission filter element (6 micron) should in-itially be replaced every 1000 hours of operation orsooner if the warning light indicates high restriction.This maintenance interval may be be increased orreduced, depending on operating conditions, by ob-serving the warning light indicator.

Service

1. Remove the filter bowl and discard the elementand O-ring seal. Refer to Figure 2-6.

2. Remove the differential pressure switch and testfor proper operation using a tester as shown inFigure 2-7. (Kent-Moore Part Number J-33884-4or similar). Refer to Section "M", Special Tools, foradapter to be used with this tester.

a. Insert switch in tester adapter.

b. Attach an ohmmeter to pins ‘‘C’’ and ‘‘B’’.

c. Apply pressure to the switch while observingthe ohmmeter:

1.) With NO pressure applied, the ohmmetershould indicate infinite resistance (open cir-cuit).

2.) As pressure is increased to 16 ± 3 PSI (110± 21 kPa) the contacts should close andindicate 0 ohms.

3. If switch does not operate within the specifiedtolerance range, install a new switch.

4. Thoroughly clean and dry all component parts.

5. Install a new filter element and O-ring and assem-ble bowl onto filter head.

FIGURE 2-6. TRANSMISSION FILTER ASSEMBLY

1. Filter Assembly 4. O-Ring Seal 2. Filter Bowl 5. Pressure Switch 3. Filter Element

FIGURE 2-7. DIFFERENTIAL PRESSURE SWITCHTESTER

F2-4 Transmission F02003 5/92

TRANSMISSION OIL COOLER

Transmission oil cooler repairs should be performedby a qualified repair facility. The bottom tank and gas-kets are available as replacement components. Con-tact your HAULPAK® distributor.

The bottom tank of the radiator contains the heatexchanger for the transmission. If a leak occurs in theheat exchanger, antifreeze/coolant may contaminatethe transmission oil and/or transmission oil may con-taminate the engine cooling system.

If the engine coolant is found to be contaminated withoil, the system must be examined for leaks and cor-rected. Then the system must be flushed to remove oilcontamination and refilled with a clean coolant solu-tion.

If a leak has been found or suspected in the heatexchanger, the transmission oil must be examinedIMMEDIATELY. Ethylene glycol (even in smallamounts) will damage friction-faced clutch plates.Contact your HAULPAK® distributor for ethylene glycoldetection test kits.

If ethylene glycol is found in the transmission oil, thetransmission should be removed, completely disas-sembled, cleaned and examined, and ALL friction-faced clutch plates replaced.

Removal And Installation

Refer to Section "C", Engine, Fuel, Cooling And AirCleaner, for the removal and installation of the radiator.

Repair

Repairs to transmission cooler and wet disc brake heatexchanger should be done by a qualified repair facility

The Wet Disc Brake heat exchanger is also mountedto the lower radiator tank. Refer to Section C. "Engine,Fuel, Cooling And Air Cleaner" for removal and repair.

F03003 Transmission Oil Cooler F3-1

NOTES

F3-2 Transmission Oil Cooler F03003

POWER TAKE OFF (PTO)

PTO GEARBOXThe power take-off (PTO), which drives the hydraulicpump, is mounted on and driven by the transmissionconverter section.

The gears and bearings in the PTO are lubricated byan external line from the transmission through drilledpassages to the bearings.

Power Take-Off Removal

Tag or mark all lines prior to disconnection or removal.Tagging lines will aid in proper hookup of lines duringinstallation. Capping all disconnected lines will reducepossible contamination.

NOTE: If hydraulic pump does not need servicing, thehydraulic system does not need to be opened toremove the PTO.

1. Park truck on a level surface, block wheels andapply park brake.

2. Turn keyswitch "Off" and shut down engine. Wait90 seconds for steering accumulator to bleeddown. Rotate steering wheel back and forth; nomovement should occur.

3. Place clean container [transmission holds ap-proximately 20 gal. (76 l)] under transmission.Remove drain plug on bottom of transmission anddrain oil. Replace drain plug and tighten securelyafter oil has drained.

4. Remove and cap lubrication line (2, Figure 4-1)from PTO.

5. Support PTO. Remove the four capscrews (5) andfour nuts (4) securing the Power Take-Off to thetransmission. While supporting the weight of thePower Take-Off and hydraulic pumps, slide theassembly away from the transmission until thePTO gear is disengaged from the transmission. AsPTO is moved from transmission, observe andretain shims between PTO mounting flange (3)and converter housing (1).

6. Remove hoist and steering pumps only if the PTOrequires disassembly. Refer to "Hoist Pump Re-moval and Steering Pump Removal" in Section"L", Hydraulic System, if necessary.

Power Take-Off Installation

1. Install new shims equal to what was removed.Shims are 0.010 in. (0.25 mm) and 0.020 in. (0.51mm) thick.

2. Install PTO to converter housing. Tighten nuts (4)and capscrews (5) to standard torque.

3. Remove cover (7) from converter housing so gearcan be held when checking PTO backlash.

4. Remove plug (6, Figure 4-1) from PTO housing foraccess to PTO driven gear.

5. Backlash between transmission gear and drivengear of PTO should be 0.005 to 0.025 in. (0.12 to0.63 mm).

a. If backlash is less than 0.005 in. (0.12 mm), addone 0.010 in. (0.25 mm) shim. Add shims asnecessary to establish required backlash.

b. If backlash is greater than 0.025 in. (0.63 mm),remove one 0.020 in. (0.51 mm) shim and re-place with one 0.010 in. (0.25 mm) shim.

6. After establishing backlash, install cover (7) onconverter housing.

7. Install plug (6) in PTO housing.

8. Connect lube line (2) to PTO.

FIGURE 4-1. P.T.O. INSTALLATION(Shown Without Hydraulic Pump)

1. Converter Housing 5. Capscrews and2. PTO Lubrication Line Lockwashers3. PTO Mounting Flange 6. Plug 4. Nuts and Lockwashers 7. Converter Cover

F04003 3/92 Power Take Off (PTO) F4-1

9. Install pumps to PTO, if removed. Refer to "HoistPump and Steering Pump Installation" in Section"L", Hydraulic System, if necessary.

10. Install transmission guard, if removed. Tightencapscrews to standard torque.

11. Refer to "Transmission Installation", this section, fortransmission filling instructions.

12. Remove blocks from wheels if truck is to be oper-ated.

PTO Disassembly

1. Remove hoist and steering pumps if they are stillinstalled. Refer to "Hoist Pump Removal andSteering Pump Removal" in Section "L", HydraulicSystem, if necessary. Observe splines of PTOoutput shaft and both pump shafts for spline wear.Match mark pump adapters (11, 27, Figure 4-2) tohousing (4).

2. Remove capscrew and retainer (15, 16) from drivegear shaft (14).

3. Remove drive gear shaft (14). As shaft is removed,needle bearings (20) can fall out of gear bore.There should be a total of 42 needles.

4. Remove drive gear (21) and thrust bearings (22)from housing.

5. Remove capscrews (12) attaching pump adapter(11) to housing. Remove adapter, observe num-ber and location of plastic shims (7, 8, 9).

6. Push pump drive shaft (1) to remove bearing cups(6) from housing.

7. Pull bearing cones (5) from pump drive shaft (1).

8. Remove capscrews attaching pump adapter (27)to housing. Remove adapter, observe numberand location of plastic shims.

9. Slide pump drive shaft from driven gear (3) andspacers (2).

10. Remove remaining bearing cone from shaft.

11. Remove seals (10) from pump adapters (11, 27).

12. Inspect all parts and replace as necessary.

FIGURE 4-2. P.T.O. ASSEMBLY

1. Pump Drive Shaft 13. O-Ring 2. Spacers 14. Drive Gear Shaft 3. Driven Gear 15. Capscrew 4. Housing 16. Retainer 5. Bearing Cones 17. O-Ring 6. Bearing Cups 18. Thrust Washer 7. Shims 19. Spacer 0.003 in. (0.076 mm) 20. Needle Bearing 8. Shims 21. Drive Gear 0.010 in. (0.254 mm) 22. Thrust Bearing 9. Shim Gasket 23. Thrust Bearing Spacer10. Seal 24. O-Ring11. Pump Adapter 25. Pipe Plug12. Capscrew 26. O-Ring

27. Pump Adapter

F4-2 Power Take Off (PTO) F04003 3/92

PTO Assembly

1. Clean all parts thoroughly.

2. Install new seals (10, Figure 4-2) in pump adapters(11, 27) with lip toward PTO housing.

3. Install one bearing cone on pump drive shaft. Besure cone is tight against shaft shoulder.

4. Position spacers (2) and driven gear (3) in housing,recessed side of gear toward inspection plug sideof housing.

5. Slide shaft (1) through two spacers (2) and gear(3).

6. Install bearing cup (6) into housing.

7. Install new shim gasket (9) and new shims (7, 8)equal to what was removed.

8. Align match marks. Install pump adapter (11).

9. Install mounting capscrews. Tighten to 90 ft. lbs.(122 N.m) torque.

10. Support end of pump drive shaft.

11. Install other bearing cone. Be sure inner race istight against shaft shoulder.

12. Install bearing cup.

13. Install one new shim gasket (9) and shims equal towhat was removed (7, 8).

14. Align match marks, install pump adapter (27).

15. Install mount capscrews. Tighten to 90 ft. lbs. (122N.m) torque.

16. Bearing end clearance should be from 0.005 in.(0.127 mm) loose to 5-12 in. lbs. (0.56-1.37 mm)rolling torque, tight.

17. If bearing adjustment is not in this range, adjustplastic shims of pump adapter.

18. Install new O-ring (24) in drive gear shaft bore.Lubricate with clean C-4 oil.

19. Install O-ring (17) to pump drive shaft (14). Lubri-cate with clean C-4 oil.

20. Position spacer (19) in center of drive gear.

21. Place 21 needles (20) on either side of spacer. Usepetroleum jelly to hold needles in place.

22. Position thrust bearing spacers (23), thrust bearing(22) and drive gear in housing.

23. Install shaft (14) and shaft retainer (16) and cap-screws (15). Tighten retainer capscrew to 16-18 ft.lbs. (22-27 N.m) torque.

24. Install any plugs removed from shaft or housing.

F04003 3/92 Power Take Off (PTO) F4-3

NOTES

F3-2 Transmission Oil Cooler F03003

DRIVELINESThe engine/transmission and transmission/final drivedrivelines are similar except in length. The frontdriveline is approximately 22 in. (56 cm) and the rear isapproximately 51.5 in. (131 cm) in length.

Removal

Removal and installation procedures for each drivelineare identical.

Block wheels securely before removing the driveli-nes. The parking brake will not be effective whenthe rear driveline is removed.

1. Remove driveline protector if equipped.

2. Remove and tag any wiring or hoses which mayinterfere with removal.

2. Attach a sling hoist to the driveline.

3. Remove the four 12-point capscrews at each crossand bearing and remove the driveline.

Installation

1. Position driveline between transmission (or finaldrive) and align the cross and bearings with thedrive flanges.

2. Install the 12-point capscrews and tighten to thefollowing torque:

Front Driveline:100 ± 5 ft. lbs. (136 ± 7 N.m)

Rear Driveline:100 ± 5 ft. lbs. (136 ± 7 N.m)

3. Install driveline protector if equipped. Tighten cap-screws to standard torque

4. Install wiring or hoses removed to gain access todriveline.

Disassembly

1. Remove the 12 Pt. Capscrews and cross andbearing from each end of driveline and inspect forrough or frozen bearings.

Note: Do not disassemble the cross and bearings. Ifbearings are unserviceable, replace the entire part asa unit.

2. Loosen and remove felt retainer (4, Figure 5-2).

3. Match mark the two sections for realignment dur-ing reassembly. Carefully slide the sections (5 &6) apart.

4. Remove the felt retainer (4) and felt washer.

5. Clean all parts except the cross and bearing infresh solvent and blow dry with compressed air.

FIGURE 5-1. TYPICAL FRONT DRIVELINEINSTALLATION

1. Flywheel Adapter Cover2. Front Driveline

3. 12 Pt. Capscrews4. Transmission

F05001 Drivelines F5-1

6. Inspect all parts for wear and damage. If either thestub and yoke or the tube and yoke is unservice-able, both parts must be replaced with a new,balanced and matched set.

7. Insure all grease passages are clear.

Assembly

1. Install a new felt washer. Lubricate washer withfresh engine oil prior to installation. Felt must becarefully inserted into the short section withouttwisting.

2. Slide felt retainer over the long, tube section.

3. Lubricate the splines with multi-purpose grease,align halves with the match marks made duringdisassembly and carefully slide together.

4. Slide the felt retainer into place and tighten se-curely. (Do not overtighten.)

5. Insert the 12-point capscrews and attach the crossand bearings at each end. Tighten the capscrewsto 100 ± 5 ft. lbs. (136 ± 7 N.m) torque.

6. Install grease fittings if removed, and lubricate withmulti-purpose grease. (Refer to Section ‘‘P’’ forcomplete grease specification.)

NOTE: Do not overgrease. Excessive amounts ofgrease will prevent driveline from collapsing properlyfor installation.

FIGURE 5-2. TYPICAL DRIVELINE

1. 12-Point Capscrew2. Cross & Bearing Assy.3. Grease Fitting

4. Felt Retainer5. Stub & Yoke6. Tube & Yoke

F5-2 Drivelines F05001

SECTION G

DRIVE AXLE, SPINDLES AND WHEELS

INDEX

TIRES AND RIMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-1TIRES AND RIMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-1

General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-1Tire Removal From Rim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-2Tire Installation on Rim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-2

FRONT TIRE AND RIM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-3Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-3Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-3

REAR TIRE AND RIM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-4Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-4Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-4

TIRE MATCHING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G2-5

FRONT WHEEL HUB AND SPINDLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-1FRONT WHEEL HUB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-1Front Wheel Bearing and Brake Disc Replacement . . . . . . . . . . . . . . . . . . . G3-2Front Wheel Hub Installation and Bearing Adjustment . . . . . . . . . . . . . . . . . G3-2Front Wheel Spindle Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-3Front Wheel Spindle Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-4Steering Linkage Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-5Steering Linkage Ball Stud and Bearing Removal . . . . . . . . . . . . . . . . . . . . G3-5Front Wheel Toe-In Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-6

Bias Ply Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-6Radial Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G3-6

FINAL DRIVE ATTACHMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-1FINAL DRIVE ANCHOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-1

Pin Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-1Pin Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2Bearing Removal and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2Bearing Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2

PANHARD ROD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-2Bearing Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G4-3

G01008 4/92 Index G1-1

FINAL DRIVE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-1COMPLETE FINAL DRIVE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-2

DIFFERENTIAL CARRIER ASSEMBLY - SERVICE WITH COMPLETE FINAL DRIVE REMOVED FROM TRUCK . . . . . . . . G5-3

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-3Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-4

DIFFERENTIAL CARRIER ASSEMBLY -SERVICE WITH FINAL DRIVE IN PLACE UNDER TRUCK . . . . . . . . . . . . . . . G5-5

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-5Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-6Differential Cage Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-7Pinion Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-7Differential Cage Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-7Spider Gear Bearing Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-8Cleaning and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-9Spider Gear Bearing Installation . . . . . . . . . . . . . . . . . . . . . . . . . . G5-9Differential Cage Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-9Pinion Installation And Bearing Adjustment . . . . . . . . . . . . . . . . . . . G5-10Differential Cage Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . G5-11Carrier Bearing And Backlash Adjustment . . . . . . . . . . . . . . . . . . . . G5-12

FINAL DRIVE PLANETARIES AND WHEEL HUBS . . . . . . . . . . . . . . . . . . . . . . . G6-1PLANETARY DRIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-1

Planetary Drive Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-1Planetary Reactor And Ring Gear Removal . . . . . . . . . . . . . . . . . . . . . . G6-2Planetary Reactor And Ring Gear Installation . . . . . . . . . . . . . . . . . . . . . G6-2Cleaning and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-3Planetary Drive Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-3Planetary Carrier Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-3Planetary Carrier Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-4

WHEEL HUB AND BEARINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-4Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-4Bearing Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-5Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G6-5

G1-2 Index G01008 4/92

TIRES AND RIMSGeneral Information and Recommendations

The truck tires should be inspected and tire pressurechecked with an accurate pressure gauge before eachworking shift. Tire pressure will vary according tomanufacturer and local working conditions. Consultthe tire manufacturer for recommended tire pressure.

Insure valve caps are securely applied to valve stems.The caps protect valves from dirt build up and damage.DO NOT bleed air from tires which are hot due tooperation; under such circumstances, it is normal forpressure to increase in the tire due to expansion.

A bent or damaged rim which does not support thebead properly may cause abnormal strain on the tireresulting in a malfunction. If a tire should becomedeeply cut, it should be removed and repaired. Ne-glected cuts cause many tire problems. Water, sand,grit, dirt and other foreign materials work into a tirethrough a cut eventually causing tread or ply separa-tion.

Tires should be stored indoors, if possible. If storedoutdoors, cover tires with tarpaulin to keep out dirt,water and other foreign materials. Long exposure tothe sun will cause ozone cracks. Storage should be ina cool, dry, dark, draft free location. Tires should bestored vertically. If they must be laid on their sides fora short period, avoid distortion by stacking no morethan three tires on top of one another. Avoid contactwith oil, grease and other petroleum products.

Before storing used tires, clean thoroughly and inspectfor damage. Repair as necessary. When a truck isplaced in storage, it should be blocked to remove theweight from the deflated tires. If a stored truck cannotbe blocked, check air pressure and inspect tires twicea month for proper inflation pressure.

•• DO NOT weld or apply heat on the rim as-sembly with the tire mounted on the rim.Resulting gases inside the tire may ignitecausing explosion of tire and rim.

•• When inflating tires ALWAYS use a safetycage.

•• NEVER inflate a tire until the lockring is se-curely in place.

•• DO NOT stand in front of or over thelock ring during inflation procedures.

•• NEVER overinflate a tire. Refer to tire manu-facturers recommendations.

•• ALWAYS keep personnel away from awheel and tire assembly when it is beingremoved or installed.

•• DO NOT go near tires after brake fires untiltires have cooled.

•• The tire and rim weigh approximately2,800 lbs. (1271 kg). BE CERTAIN tire han-dling equipment is capable of lifting andmaneuvering the load.

Manual tire removal and installation is possible but, dueto the size and weight of the components, specialhandling equipment such as a ‘‘tire handler’’ as shownin Figure 2-1 is desirable. Consult local tire vendors forsources of equipment designed especially to remove,repair, and install large off-highway truck tires.

FIGURE 2-1. TYPICAL TIRE HANDLER

G02007 3/92 Tires and Rims G2-1

Tire Removal From Rim

When deflating tires, be wary of flying dirt anddebris. Wear eye protection at all times.

1. Remove valve core and discharge air pressurecompletely from tire.

Prying against tire bead may cause damage to tirebead and will cause air leaks.

2. Break tire loose from bead seat band (2, Figure2-2).

3. Force bead seat band (2), side ring (1) and tireaway from lockring (3). Remove lockring.

4. Remove O-ring (4) from rim.

5. Remove bead seat band and side ring.

6. Break tire bead loose from back flange side of rim.

7. Remove tire from rim (5).

Tire Installation On Rim

1. Clean all rim components.

2. Install new spud (10, Figure 2-5), if necessary.

3. Install side ring against back flange.

4. Apply tire mounting solution to beads of tire.

5. Install tire on rim. Avoid prying against tire beads.

6. Install side ring (1, Figure 2-2) and bead seat band(2).

7. Force bead seat band against tire so O-ring (4)can be installed.

8. Install lockring (3). Be sure lockring is completelyin groove.

Use a safety cage whenever possible. Stand awayfrom lockring side of rim as tire is being inflated.Never start inflating unless lockring is securely inplace. Do not stand in front of, or over, lockringwhen inflating.

9. Remove core from valve stem.

10. Attach an extension hose with a clip-on air chuck,remote gauge, and a filtered air supply and inflatetire to seat tire beads and rim components againstlockring.

11. Discharge air after seating beads, install valve coreand inflate to tire manufacturer’s recommendedpressure.

Be sure that correct wheel parts are used for as-sembly. Use of non-compatible parts may notproperly secure the assembly which will result inviolently flying parts upon inflation.

When mounting a used tire, carefully check tireexternally and internally for cuts, interior casingbreaks, torn tread, or damaged beads.

FIGURE 2-2. RIM COMPONENTS

1. Side Ring 4. O-ring2. Bead Seat Band 5. R im3. Lock Ring

G2-2 Tires and Rims G02007 3/92

FRONT TIRES AND RIMS

Removal

1. Apply parking brake and block rear wheels.

2. Turn key switch "Off", shut down engine and waitat least 90 seconds to bleed down steering accu-mulator. Rotate steering wheel back and forth tobe sure no pressure remains. As a safety precau-tion, also bleed down brake accumulators. Referto Section "J", Brake Accumulator BleeddownProcedure.

3. Place jack under spindle or under frame directlybehind horsecollar structure.

4. Raise front end of truck until tire clears ground;block up securely under frame.

When deflating tires, be wary of flying dirt anddebris. Wear eye protection at all times.

5. Release air from tire.

Do not totally deflate tire. Keep tire inflated to 10-15psi (69-103 kPa) to assure tire and rim componentsremain assembled during tire handling.

6. Inspect brake components for damage or wear.Inspect hydraulic brake lines for leaking fittings ordamage.

7. Grasp tire assembly with the tire handler.

Do not damage the tire inflation stem during tireremoval.

8. Remove nuts (1, Figure 2-3). Remove lugs (2).

9. Move wheel and tire assembly away from wheelhub and into clean work area.

Due to its size and weight, always keep personnelaway from a wheel and tire assembly when it isbeing removed or installed.

Installation

NOTE: Remove all dirt and rust from mating partsbefore installing wheel assembly.

1. Grasp tire assembly with the tire handler and moveinto position on wheel hub. Install wheel lugs (2,Figure 2-3) and nuts (1). Using a 180o crisscrosspattern, alternately tighten each nut to 75 ft. lbs.(101 N.m) torque. Continue tightening nuts inincrements of 75 ft. lbs. (101 N.m) until 300 ± 30ft. lbs. (407 ± 41 N.m) torque is obtained on eachnut.

2. Check tire inflation for tire manufacturer’s recom-mended pressure. Raise truck and remove allblocking.

3. Operate truck for one load and tighten wheel nutsagain to 300 ± 30 ft. lbs. (407 ± 41 N.m). Checktorque daily until 300 ± 30 ft. lbs. (407 ± 41 N.m)torque is maintained on each nut. Check torqueintermittently thereafter.

FIGURE 2-3. FRONT WHEEL INSTALLATION

1.Nuts 2. Wheel Lugs


REAR TIRE AND RIM

Removal

1. Park truck on level surface and securely blockfront tires.

2. Raise final drive enough for tires to clear groundsurface and be removed.

3. Remove rock ejector.

4. Remove inflation extension retainer capscrews (1,Figure 2-4) grommets (2) and retainer (3).

Do not damage the inflation stem during removal.Do not totally deflate tire. Keep tire inflated to 10-15psi (69-103 kPa) to assure tire and rim componentsremain assembled during tire handling.

5. After removing inflation extension retainer, deflatetires. Remove nuts (2, Figure 2-5) and retainers(3), except one nut and retainer which should beat the top position of the wheel.

6. Position tire removal apparatus (tire handler, fork-lift, etc.).

7. Remove remaining nut and retainer. Remove out-side tire and rim.

8. Remove spacer (6, Figure 2-5).

9. Remove inner tire and rim assembly.

10. Place tires off to one side lying flat. Do not lean ontruck, walls, etc.

Installation

1. Clean all tire mounting surfaces.

2. After safely inflating tires, position inner tire andrim with wheel hub. Align tire inflation extension ingroove of wheel hub so outside tire inflation ex-tension will have clearance (Figure 2-5).

3. Install spacer (6).

4. Install outer tire and rim.

5. Install retainers (3) and nuts (2). Tighten to 300± 30 ft. lbs. (407 ± 41 N.m torque).

6. Remove blocking from under truck.

7. After truck has hauled one load retighten retainernuts to 300 ± 30 ft. lbs. (407 ± 41 N.m torque).Check torque periodically until proper torque ismaintained.

FIGURE 2-4. TIRE INFLATION RETAINER-REMOVAL

1. Capscrews 3. Retainer2. Grommets

FIGURE 2-5. REAR WHEEL ASSEMBLIES

1. Side Ring 4. Rim Assembly 7. Lockring 10. Spud2. Nuts 5. Bead Seat Ring 8. O-ring3. Retainers 6. Spacer 9. Valve assembly


TIRE MATCHINGThe matching of tires on drive axle dual wheel installa-tions is important in order to achieve satisfactory life,both on the tires and on the load carrying componentsof the final drive.

To check matching of duals already mounted on thetruck, use a large square. If one tire is too small, itbecomes obvious as the square is laid across the dualtires. The square can be made from two 1 in. x 2 in.wood strips (one piece long enough to span the dualtires). The two wood strips should be squared with acarpenter’s square and rigidly fastened to maintain atrue 90o angle.

Matching of tire diameters from one side of an axle tothe opposite side is important to prevent unstable loadshifting, excess load on structural members, and rapidwear of the internal components of the final drive.

Side by side matching on dual wheel installations isnecessary to prevent excess loading on the tire havingthe larger diameter. Mismatched tires on the dualscause unequal distribution of the load. Rapid wearand/or tire blowout can result.

Exact limitations are not specified by tire manufactur-ers, but a general rule is:

Unloaded, inflated tires, when standing side byside, should not exceed a 1% maximum variationin their diameters.

Measuring of tire size is most accurate when the tire ismounted on a wheel, inflated to correct pressure, andtotally unloaded (off the truck, or off the ground, ifmounted on a truck). Use a steel tape placed in thecenter of the tread and measure the total circumfer-ence of the tire. Using the formula below, calculate thediameter, "d".

diameter "d" = measured circumference ÷ 3.1416 diameter "d" x 0.01 = Allowable Variation in size

The tires used on opposite sides of HAULPAK® Trucksshould also be limited to a 1% variation in diameter ofthe inflated, unloaded tires.


NOTES


FRONT WHEEL HUB AND SPINDLES

FRONT WHEEL HUB

Removal

Before removing any brake lines or brake circuitcomponents be sure brake accumulators are bleddown. To bleed down accumulators:

•• BLOCK WHEELS OF TRUCK!

•• Turn key switch "Off", shut down engineand wait at least 90 seconds to bleeddown steering accumulator. Rotate steer-ing wheel back and forth; no front wheelmovement should occur.

•• Brake accumulator bleeder valves are lo-cated on the Low Pressure Detection Mod-ule beneath the accumulators on the rightside of the truck.

•• Bleed down brake accumulators by turn-ing Bleeder Valve handles counterclock-wise to open. When accumulators arecompletely bled down, close bleedervalves by turning Bleeder Valve handlesclockwise. Do not leave open.

1. Refer to Front Tire and Rim Removal, this Section,and remove front tire and rim assembly.

2. Rotate wheel hub (4, Figure 3-1) so drain plug (9)is down. Drain oil into a suitable container. Hubholds approximately 1 gal. (3.8 l).

3. Disconnect and cap brake lines at brake calipers(10).

Each Brake Caliper weighs approximately 140 lbs.(63.4 kg). The Wheel Hub Assembly weighs approximately900 lbs. (408 kg). Use adequate lifting devices when lifting thesecomponents.

4. Support one brake caliper and remove calipermount capscrews (11). Remove caliper. Repeatfor other caliper.

5. Support wheel hub with an adequate lifting device.

6. Remove wheel hub cap (7), roll pin (6) and wheelnut (8).

7. Slide outboard bearing cone (5) from spindle.

8. Remove wheel hub (4) from spindle.

9. Remove seal runner (1) if necessary.

10. Remove brake disc capscrews (2) and brake disc(3) if necessary. Refer to Front Disc Brakes, Sec-tion "J" for brake disc wear limits.

FIGURE 3-1. FRONT WHEEL REMOVAL

1. Seal Runner 6. Roll Pin2. Capscrew 7. Wheel Hub Cap3. Brake disc 8. Wheel Nut4. Wheel hub 9. Drain Plug5. Bearing Cone, 10. Brake Calipers Outboard 11. Capscrews

NOTE: For illustration clarity, the brake caliper is shownin a top mounted position. The 210M has two brakecalipers per front wheel, mounted in a fore-aft position.The 140M has one brake caliper per front wheel,mounted in the aft position.

G03009 8/91 Front Wheel Hub and Spindles G3-1

Front Wheel Hub Bearing And Brake Disc Replacement

1. Remove seal (4, Figure 3-2), seal spacer (5), innerbearing cone (3) and bearing cups (2 and 1).

2. Clean all metal parts in cleaning solvent.

3. Inspect all seals and bearings and replace asrequired.

4. Check seal ring mounting area on wheel hub,brake adaptor, and spindle for damage that couldcause leakage.

5. Inspect spindle in area of bearing surfaces andradius (under seal runner) for distress or cracks.Non-destructive methods of crack detection (dyepenetrant or magnaflux) should be used.

6. Nominal Clearance Dimensions:

Wheel hub bearing cup O.D. to wheel hub bore I.D.

+ 0.002 in. to + 0.0050 in. (+ 0.05 mm to + 0.127 mm)

Outboard bearing cone I.D. to spindle O.D.

0.000 in. to + 0.0015 in. (0.0 to + 0.038 mm)

Inboard bearing cone I.D. to spindle O.D.

0.000 in. to + 0.0002 in. (0.0 to + 0.050 mm)Spindle O.D. to seal runner I.D.

0.000 in. to + 0.0040 in. (0.0 to + 0.101 mm)

7. Install bearing cups in wheel hub. Be sure bearingcups are tight against shoulder.

8. Install brake disc (7, Figure 3-2) and disc mountingcapscrews (6). Tighten to standard torque.

Front Wheel Hub Installation And Bearing Adjustment

1. Place inner bearing cone in cup (2, Figure 3-2),install seal spacer (5) and seal (4).

2. Install seal runner (1, Figure 3-3) if removed. Besure seal runner is tight against shoulder.

3. Install wheel hub (4) on spindle. Maintain supporton wheel hub until next step is completed.

4. Install outer bearing cone (6) and retaining nut (9).

FIGURE 3-2. FRONT WHEEL HUB

1. Bearing Cups 5. Seal Spacer2. Bearing Cups 6. Capscrews3. Inner Bearing Cone 7. Brake disc4. Seal

FIGURE 3-3. FRONT SPINDLE AND HUB ASSEMBLY

1. Seal Runner 8. Cap2. Capscrew 9. Retaining Nut3. Brake disc 10. Gasket4. Wheel Hub 11. Brake Calipers5. Capscrews 12. Capscrews6. Outer Bearing Cone 13. Brake Lines7. Roll Pin

G3-2 Front Wheel Hub and Spindles G03009 8/91

5. Tighten wheel hub retaining nut (9) until all bearingrollers rotate, while rotating wheel hub, thentighten to next notch and install roll pin (7).

6. Install gasket (10, Figure 3-3), cap (8) and cap-screws. Tighten capscrews to standard torque.

7. Install brake calipers (11) and capscrews (2).Tighten capscrews to 1050 ft. lbs. (1423 N.m)torque.

8. Connect brake lines (13) to calipers.

9. Rotate wheel hub until one fill/drain plug (1, Figure3-4) is horizontal and one plug is up. Fill withproper lube. Refer to Lubrication and Service,Section "P" for lube specifications.

Bleed brakes before placing truck in production. Ifnew linings and discs were installed, burnishbrakes. Refer to Brake Bleeding and Burnishing,Section "J".

Front Wheel Spindle Removal

1. Park truck on level surface. Apply park brake andsecurely block rear wheels. Shut down engine.

2. Refer to Front Tire and Rim Removal and removethese components.

3. The spindle and wheel hub may be removed fromthe suspension tube as an assembly. If the wheelhub assembly or brake disc does not requireservice, go to "WARNING" ahead of step 5.

4. Refer to "Front Wheel Hub Removal" and removethese components if the wheel hub assembly orbrake disc requires service; then go to step 6.




5. Disconnect and cap brake lines.

6. Support tie rod (2, Figure 3-5), steering cylinder(4) and spindle arm (13) near spindle (11).

7. Remove six capscrews (12).

NOTE: If all or part of the steering linkage requiresservice, Refer to "Steering Linkage Ball Stud Removal",this section.

8. Remove splined nut (1, Figure 3-6) from suspen-sion tube (2). Refer to Section "M" for Spline NutWrench.

9. Sharply strike the spindle to loosen spindle fromsuspension tube. If spindle won’t come off, applyheat in a narrow band, vertically on spindle.

10. Carefully remove spindle assembly.FIGURE 3-4. WHEEL HUB/DRAIN HOLES

1. Fill/drain Plug 2. Wheel Hub


Front Wheel Spindle Installation

1. Be certain taper of spindle bore and suspensiontube are clean and dry and free of any surfaceimperfections or roughness.

2. Raise spindle assembly onto taper of suspensiontube. Install splined nut (1, Figure 3-5).

3. Tighten splined nut to 1100 ± 100 ft. lbs. (1491± 135 N.m) torque.

4. Install spindle arm (13, Figure 3-6) on spindleassembly (11) with six capscrews (12). Tightencapscrews to 750 ft.lbs. (1017 N.m) torque.

5. Remove supports from tie rod (2), steering cylin-der (4) and spindle arm (13).

6. Refer to "Front Wheel Hub Installation" and installthese components, if removed.

7. Connect brake lines to calipers.

8. Rotate wheel hub until one drain/fill plug is hori-zontal and one plug is up. Fill with proper lube.Refer to Lubrication and Service, Section "P".

9. Install front tire. Refer to "Front Tire Installation".

10. Remove blocks or support stand.

11. Repeat Step 3.

12. Measure toe-in. Toe-in should be 0.0 to 0.625 in.(0.0 to 15.8 mm). Refer to Toe-In Adjustmentprocedure if necessary.

FIGURE 3-5. WHEEL SPINDLE AND SUSPENSION TUBE

1. Splined Nut 3. Spindle Assembly2. Suspension Tube

FIGURE 3-6. TIE ROD REMOVAL

1. Cotter Pin 7. Cover2. Tie Rod 8. Grommet3. Ball Studs 9. Race4. Steering Cylinder 10. Boot5. Nut 11.Spindle6. Capscrews 12. Capscrews

13.Spindle Arm

Bleed brakes before placing truck in production. Ifnew linings and discs were installed, burnishbrakes. Refer to Section "J" for Brake Bleeding andBurnishing.


13. Drive truck empty. Repeat Step 3.

14. Drive truck loaded. Repeat Step 3 until torque ismaintained.

Steering Linkage Removal

1. Park truck on level surface, securely block rearwheels.

Before removing any steering lines or steeringcircuit components be sure steering accumulatoris bled down. To bleed down accumulator:

•• Turn key switch "Off" to shut down engineand wait at least 90 seconds to bleeddown steering accumulator. Rotate steer-ing wheel back and forth; no movementshould occur.

NOTE: It may not be necessary to remove both endsof tie rod or steering cylinder to make ball stud andbearing repair. If steering cylinder is removed, cap andplug hose ends and cylinder ports to prevent dirt fromentering hydraulic system. When ball studs are in-stalled in tapered bores, be sure that nuts are properlytorqued to prevent movement of ball stud.

2. Support tie rod (2, Figure 3-6) or steering cylinder(4).

3. Remove cotter pin (1), loosen nut (5) on ball stud.

4. Drive wedge between mount and tie rod end orsteering cylinder end to loosen tapered stud.

5. Remove nut, pull out ball stud.

Steering Cylinder Ball Stud/Bearing Removal

1. Remove capscrews (6, Figure 3-6) cover (7) andgrommet (8).

2. Remove ball stud (3) and race (9) from the cylinderend.

Steering Cylinder Ball Stud/Bearing Installation

1. Place two halves of ball stud bearing race (9,Figure 3-6) on ball. Install snap ring.

2. Install bearing race into end of cylinder.

3. Lubricate ball and race.

4. Install grommet (8) cover (7) and capscrews (6).Tighten to standard torque.

5. Install tapered end of ball stud into mount. Tightennut (5) to 800 ± 50 ft. lbs. (1084 ± 67 N.m)torque.

Tie Rod Ball Stud/Bearing Removal

1. Remove snap ring (11, Figure 3-7) and retainer(10).

2. Push ball stud (1) and race (8) through rod end.

Tie Rod Ball Stud/Bearing Installation

1. Place two halves of ball stud bearing race (8,Figure 3-7) on ball. Install snap ring.

2. Install ball stud and bearing race into tie rod end.

3. Lubricate ball and race. Install dirt seal (9).

4. Install tapered end of ball stud into mount. Tightennut (12) to 800 ± 50 ft. lbs. (1084 ± 67 N.m)torque.

FIGURE 3-7. TIE ROD ASSEMBLY1. Ball Stud 4. Capscrew 7. Link 10. Retainer2. Socket, R.H. Thread 5. Locknut 8. Bearing Race, Split 11. Snap Ring3. Socket, L.H. Thread 6. Clamp 9. Dirt Seal 12. Nut

13. Cotter Pin


Front Wheel Toe-in Adjustment

(Bias Ply Tires)

1. Park empty truck on a level surface. Check toe-inby measuring the distance between front wheels(centerline to centerline). These measurementsshould be taken on a horizontal center line at frontand rear of tire (Figure 3-8).

2. The front measurement, Dimension "A", should be0.0 to 0.625 in. (0.0 to 15.8 mm) less than rearmeasurement, Dimension "B".

3. If adjustment is necessary, loosen clamp bolt nuts(1, Figure 3-9) on both ends of tie rod eyes.

4. Rotate tie rod (2) until 0.0 to 0.625 in. (0.0 to 15.8mm) of toe-in is obtained (Figure 3-8).

5. Tighten clamp bolt nuts (1) to standard torque.

NOTE: Be certain clamp and hardware is positioned"up" as shown in Figure 3-9. This is necessary to avoidlinkage interference during steering.

6. Remove blocks from rear wheels.

(Radial Tires)

NOTE: Set toe-in to ‘‘zero’’ with the truck fully loaded.

1. Park fully loaded truck on a level surface. Checktoe-in by measuring the distance between frontwheels (centerline to centerline). These measure-ments should be taken on a horizontal center lineat front and rear of tire (Figure 3-8).

2. The front measurement, Dimension "A", should beequal to rear measurement, Dimension "B".

3. If adjustment is necessary, loosen clamp bolt nuts(1, Figure 3-9) on both ends of tie rod eyes.

4. Rotate tie rod (2) until zero toe-in (Dimension "A"= Dimension "B") is obtained (Figure 3-8).

5. Tighten clamp bolt nuts (1) to standard torque.

NOTE: Be certain clamp and hardware is positioned"up" as shown in Figure 3-9. This is necessary to avoidlinkage interference during steering.

6. Remove blocks from rear wheels.

FIGURE 3-8. TOE-IN DIMENSIONS

FIGURE 3-9. TIE ROD ADJUSTMENT

1. Clamp, Capscrew & Nut 3. Spindle Arm2. Tie Rod 4. Frame Member


FINAL DRIVE ATTACHMENTS

FINAL DRIVE ANCHORThe final drive anchor pin bearing may be replacedwithout removing the complete final drive from truck.

Pin Removal

1. Securely block front wheels.

2. Vent all nitrogen from both front suspensions toallow front of truck to lower when blocked underhoist cylinder mounts (Step 5). Refer to Section"H", Oiling and Charging Procedures.

3. Remove drive line (2, Figure 4-1) between finaldrive and transmission and set aside.

4. Raise rear of frame until rear suspension are 1 in.(25.4 mm) from full extension.

5. Securely block under lower hoist cylinder mountstructure (3) of both sides.

6. Securely block rear wheels.

7. Vent nitrogen from rear suspensions to allow thefinal drive anchor structure to be lowered (step 13)when the anchor pin is removed. Refer to Section"H", Oiling and Charging Procedures.

8. Support anchor structure (1) so that when anchorpin is removed (step 12) it will not drop, but canbe lowered in a controlled manner far enough foranchor pin assembly to clear frame mounts.

9. Place jack under either rear suspension lowermount.

Be sure jack is secure to lower mount so it will notslide off as jack is extended.

10. Remove lock plug (1, Figure 4-2), splined nut (3)and electrical ground strap. Refer to Section "M",Special Tools, for Splined Nut Wrench.

11. Remove retainer bar (8).

12. Remove anchor pin (2).

13. As jack under rear suspension is raised, let off onanchor structure support until anchor bearing as-sembly clears frame. As anchor structure comesdown, spacer (4) can be removed.

14. Block final drive securely in this position.

FIGURE 4-1. FINAL DRIVE ANCHOR ATTACHMENT

1. Anchor Structure 3. Hoist Cylinder Mount2. Drive Line

FIGURE 4-2. FINAL DRIVE ANCHOR PIN ASSEMBLY

1. Lock Plug 6. Capscrew2. Anchor Pin 7. Final Drive Anchor 3. Splined Nut Structure4. Spacer 8. Retainer Bar5. Anchor Bearing Inner Race

G04007 Final Drive Attachments G4-1

Pin Installation

1. Raise anchor structure into position betweenframe mounts as jack under rear suspension islowered.

2. Install spacer (4, Figure 4-2).

3. Install anchor pin (2).

4. Install retainer bar (8) and capscrews (6). Tightento standard torque.

5. Install splined nut (3), tighten to 1500 ft. lbs. (2034N.m) torque. If lock plug holes do not align,tighten to next hole. Install lock plug (1). Refer toSection "M", Special Tools, for Splined NutWrench.

6. Connect electrical ground strap.

7. Install drive line. Tighten capscrews to 100 ± 5 ft.lbs. (136 ± 7 N.m) torque.

8. Raise rear of frame and remove support fromunder lower hoist cylinder mounts.

9. Charge both front and rear suspensions with nitro-gen. Refer to Section "H", Oiling and ChargingProcedures.

Bearing Removal and Inspection

1. Remove nuts (1, Figure 4-3), capscrews (2) andretainer (3) from anchor structure.

2. Remove bearing carrier (6) from anchor structure.

3. Remove bearing (4) from carrier.

4. Inspect anchor pin, bearing, bearing carrier, andbore of anchor structure. Replace any damagedor worn component.

5. Nominal Clearance Dimensions:

Bearing carrier O.D. to anchor structure bore I.D.

+ 0.0010 to + 0.0030 in. (0.025 mm to 0.076 mm).

Bearing O.D. to carrier I.D.

+ 0.0005 to + 0.0015 in. (0.013 mm to 0.038 mm).

Bearing I.D. to pin O.D.

+ 0.0008 to 0.002 in (0.020 mm to 0.050 mm).

Bearing Installation

1. Clean all parts.

2. Install bearing assembly (4, Figure 4-3) into carrier(6). Be certain outer race is against shoulder ofcarrier.

3. Install carrier into bore of anchor structure (5).

4. Install bearing retainer (3), capscrews (2) and nuts(1). Tighten to standard torque.

PANHARD ROD

Removal

1. Park truck on level surface and securely blockwheels.

2. Securely support frame on each side under lowerhoist cylinder mounts (3, Figure 4-1).

3. Support panhard rod (1, Figure 4-4).

4. Remove nuts (3), capscrews (2) and retainers (4)from both panhard rod pins (5).

5. Remove panhard rod pins and panhard rod fromframe and final drive case.

Installation

1. Raise panhard rod into position.

2. Install pins

When installing panhard rod, misalignment of sec-ond pin and bearing will probably occur. Raise orlower frame with jacks or adequate lifting deviceON EACH SIDE OF FRAME. DO NOT use rear suspensions, because there is norestraint to keep frame from shifting to one side orthe other.

FIGURE 4-3. ANCHOR PIN BEARING

1. Nut 4. Bearing Assembly2. Capscrew 5. Anchor Structure3. Bearing Retainer 6. Bearing Carrier

G4-2 Final Drive Attachments G04007

3. Install retainers (4), capscrews (2) and nuts (3).Tighten capscrews to standard torque.

Bearing Replacement

1. Remove one snap ring (1, Figure 4-5) from eachend of panhard rod bores.

2. Remove bearing (2) from each end of panhard rod.

3. Inspect panhard rod pin bearing bores. Replaceany component damaged or worn beyond thefollowing limits:

Nominal Clearance Dimensions:

Bearing O.D. to panhard rod bore I.D.

0.0004 in. to + 0.0018 in. (0.010 mm to 0.045 mm).

Bearing I.D. to pin O.D.

0.0000 in to + o.0006 in. (0.000 mm to 0.015 mm).

Panhard rod pin mount bores I.D. to pin O.D.

+ 0.0010 in. to + 0.0040 in. (0.025 mm to 0.101 mm).

4. Clean all parts being reused.

5. Install bearing (2) in each end of panhard rodbearing bore firmly against snap ring.

6. Install other snap ring (1) for both bearings.

FIGURE 4-4. PANHARD ROD ATTACHMENT

1. Panhard Rod 4. Retainers2. Capscrew 5. Panhard Rod Pin3. Nut

FIGURE 4-5. PANHARD ROD BEARING

1. Snap Rings 2. Bearing Assembly

G04007 Final Drive Attachments G4-3

NOTES

G4-4 Final Drive Attachments G04007

FINAL DRIVE ASSEMBLYThe 210M HAULPAK® final drive assembly consists ofa differential assembly, two oil cooled wet disc brakeassemblies, and two outboard mounted planetarydrive assemblies.

The power path enters the final drive through a straddlemounted bevel pinion which drives a ring gear anddifferential cage. The differential cage drives side gearsthrough the spider pinion and cross. The side gearsdrive sun pinion shafts to planet sun gears in the wheelhub planetaries. The planet gear carrier attached towheel hub reacts against a fixed planetary ring gear todrive the rear wheels of the truck. See Figure 5-1.

COMPLETE FINAL DRIVE ASSEMBLY

Removal

NOTE: The Differential Carrier Assembly may be serv-iced without removing the complete final drive assem-bly from under the truck. Instructions for this service iscovered later in this section.

Make sure jacks, lifting equipment and rigginghave adequate capacity and are securely attachedto raise and hold rear of truck until blocking orsupport stands are securely installed. Total weightof rear end of truck (without body liners) is approxi-mately 48,000 lbs. (21 792 kg). Weight of final driveassembly with tires is approximately 24,000 lbs. (10896 kg).

1. Park truck on level surface.

2. Securely block front tires.

3. With engine running, release parking brake anddisconnect linkage. Refer to Section "J", ParkingBrake Removal for instructions for disconnectingparking brake linkage. Shut down engine.

4. Raise rear of frame high enough to clear final drivecase as it is rolled from under truck.

5. Securely block under lower hoist cylinder mountstructure (3, Figure 5-2) of frame.

6. Block rear wheels to prevent final drive assemblyfrom moving.

7. Remove drive line (2) between final drive andtransmission. Slide drive line out of protector andset aside. FIGURE 5-1. FINAL DRIVE ASSEMBLY

G05006 02/92 Final Drive Assembly G5-1


•• Turn key switch "OFF", shut down engineand wait at least 90 seconds to bleeddown steering accumulator. Rotate steer-ing wheel back and forth; no front wheelmovement should occur.


8. Disconnect all hydraulic lines to wet disc brakeassemblies. Cap/plug all ports and hoses to pre-vent dirt entry.

9. Remove rock ejectors from both sides of body.

10. Completely vent nitrogen from both rear suspen-sions. Refer to Section "H", Oiling and ChargingProcedures.

11. Attach lifting device to a rear suspension. Refer toSection "H", Rear Suspension Removal. Removeboth suspensions.

12. Refer to Final Drive Attachment, this Section, forAnchor Pin and Panhard Rod Removal. Removethese components.

NOTE: If differential is completely locked up, it will benecessary to remove wheel planetary sun gears sofinal drive assembly can be rolled out from underframe. Refer to Figure 5-4.

13. Remove any electrical wiring or lube lines that mayinterfere with removal of the final drive assembly.

14. Remove blocks from behind rear wheels.

15. While supporting anchor structure, roll final driveout from under frame.

Installation

1. Align final drive assembly to frame.

2. Roll final drive under frame and block wheels.

3. Raise anchor structure (1, Figure 5-2) into positionbetween frame mount. Refer to Final Drive Attach-ment, this Section, for Anchor Pin Installation.Install Anchor Pin.

4. Raise panhard rod to connect to frame. Refer toFinal Drive Attachment, this Section, for PanhardRod Installation. Install Panhard Rod.

5. Attach lifting device to a rear suspension. Refer toSection "H", Rear Suspension Installation. Installboth suspensions.

6. Install drive line (2) with slip joint end towardtransmission. Tighten companion flange cap-screws to 100 ± 5ft.lbs.(135.6 ± 6.8Nm) torque.

7. Install all hydraulic lines to rear brake assembliesand connect electrical ground strap at anchor pin.

Before placing truck in production, brakes must bebled. Refer to Section "J" for Brake Bleeding pro-cedure.

8. Install rock ejectors on both sides of body.

FIGURE 5-2. FINAL DRIVE ANCHOR ATTACHMENT

1. Anchor Structure 3. Hoist Cylinder Mount2. Drive line

G5-2 Final Drive Assembly G05006 02/92

9. Raise rear of frame and remove blocks or supportstands from under lower hoist cylinder mountstructure.

10. Start engine, release parking brake, install linkagefrom park brake actuator to park brake lever.Refer to Section "J", Parking Brake Installation forinstructions for connecting parking brake linkage.Apply park brake, shut down engine.

11. Charge all suspensions. Refer to Section "H",Suspension Oiling and Charging Procedure.

DIFFERENTIAL CARRIER ASSEMBLY --SERVICE WITH COMPLETE FINALDRIVE ASSEMBLY REMOVED FROMUNDER TRUCK

Removal

This removal procedure is with tires and rims installedon wheel hubs. Position final drive assembly in workarea and securely block rear wheels.

1. Thoroughly clean front of differential carrier as-sembly (2, Figure 5-3) and front of final drive case.

2. Prepare to drain 53 gal. (200 l) of oil from final drivecase. Remove drain plug.

3. Raise anchor structure (5) to vertical position andhold.

4. Securely block final drive case so it will not rotateas differential assembly is removed and installed.

5. Remove capscrews (4) securing anchor structure(5) to final drive case.

NOTE: Match mark anchor structure to final drive caseas it is possible to install anchor structure upsidedown.

6. Lift anchor structure from final drive case.

7. Remove sun gear cover (4, Figure 5-4) from bothwheel planet carriers.

FIGURE 5-3. DIFFERENTIAL CARRIER ASSEMBLY

1. Capscrews 3. O-Ring 2. Differential Carrier 4. Capscrews Assembly 5. Anchor Structure

FIGURE 5-4. PLANETARY DRIVE ASSEMBLY

1. Thrust Bushing 6. Snap rings2. Sun Gear Shaft 7. Sun Gear3. O-ring 8. Drain Plug4. Sun Gear Cover 9. Ring gear5. Thrust Plug


8. Remove thrust plug (5) from end of sun gear shaft(2) in each wheel.

9. Take off snap rings (6). Slide out sun gears (7).

10. Pull out sun shaft (2) approximately 12 in. (304mm) on each side.

11. Remove capscrews (1, Figure 5-3) securing differ-ential carrier assembly to final drive case.

12. Install a capscrew in each of the threaded holes ofthe carrier flange. Tighten evenly to raise differen-tial carrier.

13. After differential carrier assembly is raised, placea steel wedge between flange and case to holdcarrier assembly. Remove puller capscrews.

14. Install lift eyes in threaded holes of flange.

NOTE: The ring gear is on left side of assembly whenviewed from rear of final drive case, as it is installed intruck. Adjust rigging so pick point is approximately atedge of companion flange retainer plate toward ringgear side, so assembly comes out straight.

15. Attach lifting device and raise assembly from finaldrive case.

Installation

1. Install O-ring (3, Figure 5-3) on differential carrierassembly pilot diameter.

2. Coat pilot and O-ring with clean gear lube oil of thesame type used in final drive assembly.

3. Install two 0.750 in. x 3" guide bolts in bolt circleof final drive case.

4. Position differential carrier assembly above finaldrive case. Align carrier support bosses (A, Figure5-5) with bosses in final drive case.

5. Lower carrier into case. Observe that O-ring is notdamaged as carrier goes into the final drive case.

6. Install capscrews (1 Figure 5-3) and tighten tostandard torque.

7. Position anchor structure (5) on final drive case,aligning match marks provided at disassembly. Ifno match marks were made, anchor pin bearingbore must be above spiral bevel pinion center linewhen pinion is horizontal.

8. Install anchor structure mount capscrews (4).Tighten to standard torque.

9. Slide each sun gear shaft (2, Figure 5-4) intodifferential.

10. Install thrust bushing (1) on sun gear shaft ifremoved.

11. Install sun gear (7) it may be necessary to rotatecompanion flange to engage sun gears to pinionshaft and planet gears.

12. Install snap rings (6) and thrust plugs (5).

13. Install sun gear covers (4) O-rings (3) and cap-screws. Tighten to standard torque.

14. Attach lifting device to anchor structure. Removeblocks and rotate anchor structure to ground.

15. Fill final drive housing at center case fill plug untiloil level is at bottom of fill hole. Oil must flow fromcenter housing out to both planetaries; add oiluntil level is maintained at bottom of fill hole. Allowapproximately 15 minutes for a proper fill.

A complete fill will require approximately 53 gal.(200 l) of oil. Refer to Lube Chart, Section "P", forproper gear lube oil.

FIGURE 5-5 . INSTALLING DIFFERENTIAL CARRIER


DIFFERENTIAL CARRIER ASSEMBLY --SERVICE WITH FINAL DRIVE IN PLACEUNDER TRUCKNOTE: To prevent dirt from entering final drive case asdifferential assembly is removed and installed, thor-oughly clean under side of body and all surroundingcomponents.

Removal

1. Position all four rear tires on 8 inch blocks to allowfor clearance when removing differential assem-bly from under truck. Securely block wheels sotruck will not move.

2. Position a container which will hold at least 53 gal.(200 l) of oil under final drive case. Remove drainplug and drain oil from final drive.

3. Raise body and install body up pins (1, Figure 5-6).

4. Remove clamps (3, Figure 5-7) from exhausttubes.

5. Remove exhaust box (1), mount capscrews (2).

6. Remove left hand exhaust pipe spring clamp (4).Move left hand exhaust pipe as far left as possible.

7. Remove drive line capscrews. Remove drive line(2, Figure 5-2) and drive line protector.

8. Set drive line aside.

9. Remove planetary sun gear covers (4, Figure 5-4).Pull sun gear shafts (2) out on each side approxi-mately 12 in. (304 mm).

10. Remove top two differential assembly mount cap-screws (1, Figure 5-8).

11. Attach lifting bracket (2) with two capscrews tothreaded holes of differential carrier housing. Po-sition bracket so capscrews are in center of slotholes of bracket for assembly removal.

12. Attach lifting device to bracket.

13. Place a metal plate [1/8 -- 1/4 in. (3-6 mm) thick by4 ft. (1.22 m) square] under anchor structure. Thedifferential assembly will be set on the plate andplate will then be pulled from under truck.

FIGURE 5-6. BODY UP PIN INSTALLATION


FIGURE 5-7. EXHAUST PIPING

1. Exhaust box 3. Clamps2. Mount capscrews 4. Spring Clamp

FIGURE 5-8. DIFFERENTIAL ASSEMBLY REMOVAL

1. Capscrews 3. Threaded holes2. Lifting bracket


14. Remove remaining differential assembly mountcapscrews.

15. Install two puller bolts in threaded holes (3) to startdifferential assembly out of case.

16. Support differential assembly with lifting devicemanuever differential toward front of truck untilcarrier bolt flange contacts anchor structure. Re-fer to Figure 5-9.

17. Rotate ring gear side of assembly into final drivecase and lower slightly until assembly is clear offinal drive housing. (Figure 5-9).

18. Lower assembly to plate.

19. Remove plate and assembly from under truck.

Installation

1. Body should be raised and cleaned and exhaustpiping removed as described in "Removal".

2. Position differential assembly on plate at front ofright rear wheels.

3. Attach lifting bracket (2, Figure 5-8) to threadedholes at top of carrier bolt flange. Adjust liftingbracket as necessary by making trial lifts. The ringgear should be vertical and face of carrier boltflange should be nearly parallel to face of finaldrive case.

4. Position plate under truck aligning it with theanchor structure. Attach lifting device and raiseassembly.

NOTE: As differential assembly is raised into position,be sure no dirt enters final drive case or is present onassembly.

5. Manuever assembly so carrier flange is contactinganchor on both sides. (Figure 5-9).

6. Install four guide bolts in face of final drive case.

7. Completely coat pilot of differential carrier andO-ring with clean gear lube oil of the same typeused in final drive assembly.

8. Move differential assembly into final drive casealigning guide bolts with holes in carrier boltflange.

9. When carrier pilot contacts final drive bore, installfour equally spaced puller capscrews.

10. As carrier is pulled into final drive case, keep finaldrive case face and carrier bolt circle flange par-allel. This will prevent O-ring from being cut.

11. Pull assembly completely into case.

12. Remove guide bolts and puller bolts. Install mountcapscrews and tighten to standard torque.

13. Remove lifting bracket, install remaining mountcapscrews.

14. Install drive line with slip joint end toward transmis-sion. Tighten companion flange capscrews to 100± 5 ft. lbs. (135 ± 6.8 Nm) torque.

15. Install drive line protector.

16. Position exhaust box to exhaust tubing (Figure5-7).

17. Install exhaust box mount capscrews. Tighten tostandard torque.

18. Install all exhaust tubing clamps.

19. Slide each sun gear shaft (2, Figure 5-4) intodifferential. Install covers. Tighten capscrews tostandard torque.

20. Remove body up retaining pins and lower body.

21. Remove blocks from under rear wheels.

22. Fill final drive housing at center case fill plug untiloil level is at bottom of fill hole. Oil must flow fromcenter housing out to both planetaries; add oiluntil level is maintained at bottom of fill hole. Allowapproximately 15 minutes for a proper fill.

A complete fill will require approximately 53 gal.(200 l) of oil. Refer to Lube Chart, Section "P", forproper gear lube oil.

FIGURE 5-9. DIFFERENTIAL ASSEMBLY REMOVAL/INSTALLATION


Differential Cage Removal

Differential assembly repair is best accomplished usinga stand to support differential carrier. Refer to Section"M", Special Tools, for instructions for fabricating stand.

1. Position carrier assembly in stand (10, Figure 5-10)with ring gear up as illustrated.

2. Inspect carrier housing (9) and differential carrierbearing caps (5) for match marks. If componentshave not been previously match marked, stampmatch marks at this time. Caps and carrier are amatched set when machined and therefore mustbe installed in correct position at assembly.

3. Remove capscrews (6) and locks (7).

4. Attach lifting device and support differential as-sembly.

5. Remove capscrews (4), bearing caps (5), adjust-ing nuts (2), and bearing cones (1).

6. Raise differential cage assembly (3) from carrierhousing (9).

Pinion Removal

1. Position carrier assembly in stand with companionflange (3, Figure 5-11) up as illustrated.

2. Remove capscrews (4), retainer plate (5), andcompanion flange (3).

3. Remove capscrews (2) and bearing retainer (1).Threaded pusher bolt holes are present to assistin removal of retainer.

4. Remove pinion (6) and bearings assembly.

5. Remove pinion nose bearing cup (7) and shims(8) from carrier.

Differential Cage Disassembly

1. If necessary, remove ring gear mount capscrews(8, Figure 5-12) and ring gear (7).

FIGURE 5-10. DIFFERENTIAL ASSEMBLY

1. Bearing Cups 6. Capscrews2. Adjusting Nuts 7. Locks3. Differential Cage 8. Carrier Bearing Cones Assembly 9. Carrier Housing4. Capscrews 10. Stand5. Bearing Caps

FIGURE 5-11. DIFFERENTIAL PINION

1. Bearing Retainer 5. Retainer Plate2. Capscrews 6. Pinion 3. Companion Flange 7. Pinion Nose Bearing 4. Capscrew Cup

8. Shims


2. Inspect differential cap (1) and carrier (12) formatch marks. If not present, stamp marks; theassembly is machined as a matched set.

3. Remove carrier bearing cones (9), if necessary.

4. Remove capscrews (2) and cap (1).

5. Remove side gear (4) and thrust washer (5).

6. Remove cross (3) and spider gear assemblies (6).

7. Remove other side gear and thrust washer fromcarrier.

Spider Gear Bearing Removal

1. Hold head of bearing sleeve (1, Figure 5-13). SeeSection "M", Special Tools, for fixture (2) that willhold spider assembly for nut removal and instal-lation.

2. Bend back tab of lockwasher (3) and remove nut(4). See Section "M", Special Tools, for special nutwrench (5).

3. Remove sleeve (1, Figure 5-14) from bearingcones (2 & 4).

4. Remove bearing cups (7 & 9) from spider gear (8).

FIGURE 5-12. DIFFERENTIAL CAGE ASSEMBLY

1. Differential Cap 7. Ring Gear 2. Capscrews 8. Capscrews3. Cross 9. Carrier Bearings4. Side Gear 10. Roll Pin5. Thrust Washer 11. Roll Pin6. Spider Gear Assembly 12. Ring Gear Carrier

FIGURE 5-13. REMOVING/INSTALLING NUT ON SPIDER GEAR ASSEMBLY

1. Bearing Sleeve 4. Nut2. Pinion Assembly 5. Differential Locknut Torquing Base Wrench3. Lockwasher

FIGURE 5-14. SPIDER GEAR ASSEMBLY

1. Bearing Sleeve 6. Lockwasher2. Bearing Cone (large) 7. Bearing Cup (small)3. Spacer 8. Spider Gear4. Bearing Cone (small) 9. Bearing Cup (large)5. Nut 10. Roll Pin Slot



1. Clean all parts thoroughly in clean solvent andblow dry with shop air. Lightly coat parts with justenough clean oil to prevent rust formation onmachined and bearing surfaces.

2. Check all pinion, ring gear and side gear teeth fordamage, excessive wear or cracks. Inspect allsplines for defects. Use a hard stone to removeany minor burrs. If either ring gear or spiral bevelpinion is damged, both will have to be replaced,as the components are a matched set.

3. Bushing surfaces, bearing rollers and races mustbe free of defects - no galling, cracks or rough-ness. Bearings must turn freely and smoothly.

4. Differential carrier and cover must be free of cracksor other defects. Mating surfaces must be free ofdefects, minor imperfections may be smoothedclean with a hand stone or emery paper.

5. Inspect all differential components. Replace anydefective parts as necessary.

Nominal Clearance Dimensions:

Differential cap carrier bearing bore I.D. to bearingcup O.D.

+ 0.0010 in. to + 0.0020 in. (0.025 mm to 0.051 mm).

Bearing cup O.D. to spiral bevel pinion bearingcarrier bore I.D.

+ 0.0016 in. to + 0.0040 in. (0.041 mm to 0.102 mm).

Pinion nose bearing cup O.D. to carrier assemblynose bearing cup I.D.

0.0000 in. to + 0.0030 in. (0.000 mm to 0.076 mm).

Pinion nose bearing journal O.D. to nose bearingcone I.D.

+ 0.0008 in. to + 0.0028 in. (0.020 mm to + 0.071 mm).

Pinion outboard bearing journal O.D. to outboardbearing cone I.D.

+ 0.0015 in. to 0.0035 in. (0.038 mm to 0.089 mm).

Differential cage carrier bearing journal O.D. tobearing cone I.D.

+ 0.0022 in. to + 0.0042 in. (0.056 mm to 0.107 mm).

Ring gear I.D. to differential ring gear carrier O.D.

0.0000 in. to + 0.0040 in. (0.000 mm to 0.102 mm).

Differential cage cross pin bore I.D. to cross pinO.D.

-0.0015 in. to + 0.0015 in. (-0.038 mm to 0.038 mm).

Cross pin O.D. to spider gear bearing sleeve I.D.

+ 0.0005 in. to + 0.0035 in. (0.013 mm to 0.089 mm).

Spider gear bearing cups O.D. to spider gear cupbores I.D.

+ 0.0010 in. to + 0.0030 in. (0.025 mm to 0.076 mm).

Spider gear bearing cone I.D. to bearing sleeveO.D.

0.0000 in. to + 0.0150 in. (0.000 mm to 0.381 mm).

Side gear thrust washer minimum thickness

0.2500 in. ± 0.0010 in. (6.350 mm ± 0.025 mm).

NOTE: If bearing cones or cups are installed with apress, be sure bore or shaft is free of burrs and nicks.Lightly cover shaft or bore with oil to aid installation.When heating bearings, control temperature from250oF - 275o F (121oC - 135o C). Do not use a torch toheat bearings. After heated bearing is installed, besure it is tight against shoulder. If bearing is chilled,do not exceed -65o F (-55o C).

Spider Gear Bearing Installation

1. Install bearing cups (7 & 9, Figure 5-14) in spidergear (8) bores. Be sure cups seat firmly againstshoulders.

2. Place bearing sleeve (1) on fixture (2, Figure 5-13).

3. Install larger cone (2, Figure 5-14) and spacer (3)on sleeve.

4. Install spider gear with cups (7, 8 & 9).

5. Install small cone (4) lockwasher (6) and nut (5).

6. Using wrench (5, Figure 5-13), tighten nut to 250± 25 ft. lbs. (339 ± 34 Nm) torque. Bend tang oflockwasher into slot of nut.

Differential Cage Assembly

1. If removed, install four roll pins (11, Figure 5-12)next to cross pin bores. To be flush within 0.030in. (0.76 mm) of cage outer surface.

2. Position ring gear carrier portion of cage with ringgear flange down.


3. Install thrust washer (5). End of roll pin (10) mustbe 0.090 in. ± 0.030 in. (2.3 mm ± 0.76 mm) belowgear surface of thrust washer.

4. Install one side gear (4).

5. Install cross (3) with four spider gear assemblies(6). Align slot (10, Figure 5-14) in head of bearingsleeve with each roll pin (11, Figure 5-12).

6. Install second side gear (4).

7. Place grease or petroleum jelly on thrust washersurface of differential cage cap. Install thrustwasher. Be sure ends of roll pins (10) are 0.090 in.± 0.030 in. (2.3 mm ± 0.76 mm) below gear sur-face.

8. Install differential cap (1). Do not dislodge thrustwasher. Align match marks.

9. Install capscrews (2). Tighten to standard torqueand lock wire.

10. As ring gear (7) is installed to flange, be sure noburrs or dirt get between ring gear and flangefaces. Lube taperhead capscrews with Never-Seez and install.

11. Tighten ring gear mount capscrews (8) in a criss-cross pattern to 300 ft. lbs. (406 Nm) torque.Repeat pattern and increase torque to 600 ft. lbs.(813 Nm). Repeat pattern and increase finaltorque to 900 ft. lbs. (1220 Nm). Lock wire allcapscrews in pairs.

Pinion Installation And Bearing Adjustment

1. Set differential carrier on work surface or in fixturewith spiral bevel pinion bores up.

2. Determine amount of shims (3, Figure 5-15) to beinstalled between nose bearing cup (1) and shoul-der of carrier as follows:

a. Pinion mounting variation is marked on end ofpinion.

b. The nominal shim pack is 0.035 in. (0.89 mm)for a pinion with 0.000 in. (0.000 mm) mountingvariation.

c. If pinion being installed is stamped with [+ ]mounting variation dimension, add stampedvariation to nominal 0.035 in. (0.89 mm). If pinion is stamped with [-] mounting variationdimension, subtract stamped variation from0.035 in. (0.89 mm).

EXAMPLE:Shims for O variation: 0.035 in. (0.89 mm)Pinion being installed is stamped:

-0.015 in. (-0.38 mm)

O variation: 0.035 in. (0.89 mm)Subtract pinion marking: 0.015 in. (0.38 mm)Shim pack is: 0.020 in. (0.51 mm)

d. When assembling shim pack, measure shimsindividually. Make shim pack ± 0.001 in. (0.025mm) of answer found in Step 2c.

3. Install shims (3) and bearing cup (1) into carrier.Be sure cup is completely against shims.

4. Install nose bearing cone (2) and outboard bearingcone (12) on pinion shaft. Be sure cones are tightagainst shoulders. Lightly cover cones with oil.

FIGURE 5-15. PINION INSTALLATION

1. Nose Bearing Cup 9. Capscrews2. Nose Bearing Cone 10. Retainer3. Shims 11. Seal4. Carrier Housing 12. Outboard Bearing Cone5. O-Ring 13. Outboard Bearing Cup6. Bearing Carrier 14. Shims7. Capscrews 15. Pinion8. Companion Flange


5. Install outboard bearing cup (13) in bearing carrier(6). Be sure cup is tight against shoulder.

6. Install pinion (15) and bearing carrier (6) with noshims (14).

a. Install two mounting capscrews equallyspaced, one each, next to each 0.500 in. (12.7mm) holes.

b. Tighten the two capscrews to 70 ft. lbs. (94Nm) torque while rotating pinion a minimum ofthree times.

c. Increase torque to 140 ft. lbs. (189 Nm) whilerotating pinion a minimum of three times.

d. Repeat Step c. until capscrew torque is main-tained.

e. Loosen capscrews and rotate pinion threetimes.

7. Tighten the two capscrews to 10 ft. lbs. (13.5N.m) torque as pinion is rotated a minimum ofthree times.

a. Raise torque to 15 ft. lbs. (20.3 N.m) as pinionis rotated a minimum of three times.

b. Repeat Step 7a. until 15 ft. lbs. (20.2 N.m)torque is maintained.

8. Using a depth micrometer, measure and recordthe depth to end of the differential carrier throughthe two holes next to the capscrews.

9. Average the two measured depths and subtractthe bearing carrier flange thickness from the av-erage depth.

NOTE: If bearing carrier flange thickness is notstamped or etched, measure and record when carrieris removed for shim installation. Measure at least threeplaces equally spaced and use an average of themeasurements.

10. Add 0.003 in. (0.076 mm) to dimension establishedin Step 9 and make a shim pack within ± 0.001 in.(0.025 mm) of this dimension.

EXAMPLE:Average depth (Step 9): 1.190 in. (30.226 mm)Subtract flange thickness 1.120 in. (28.448 mm)Gap: 0.070 in. (1.778 mm)Add (Step 10) 0.003 in. (0.076 mm)Required shim pack: 0.073 in. (1.854 mm)

11. Measure shims to obtain + 0.002 in. (0.051 mm)tolerance.

12. Install O-ring (5, Figure 5-15) on bearing carrierpilot. Lightly coat with clean gear lube oil of thesame type used in final drive assembly.

13. Install shims (14) and bearing carrier (6).

14. Install capscrews (7) rotate pinion as capscrewsare tightened to standard torque.

15. Install seal (11).

16. Install companion flange (8), retainer (10), andcapscrews (9). Tighten to standard torque.

17. Lock wire capscrews (9).

Differential Cage Installation

1. Position differential carrier in fixture with piniondown. This will not affect backlash as pinion bear-ings are preloaded.

2. Install cage carrier bearing cones (8, Figure 5-16)on cage. Be sure cones are tight against shoul-ders.

FIGURE 5-16. DIFFERENTIAL ASSEMBLY

1. Bearing Cups 6. Capscrews2. Adjusting Nuts 7. Locks3. Differential Cage 8. Carrier Bearing Cones Assembly 9. Carrier Housing4. Capscrews 10. Stand5. Bearing Caps


3. Install cage carrier bearing cups (1) in differentialcarrier.

4. Install differential cage assembly in carrier.

5. Install bearing caps (5). Refer to match marks forproper position.

6. Install capscrews, tighten enough that bearingcaps are not loose.

7. Install bearing adjustment nuts (2).

Carrier Bearing And Backlash Adjustment

1. Tighten bearing cap mount capscrews (4) to 100ft. lbs. (135.6 N.m) torque.

2. Adjust nuts (2) to obtain 0.022 in. (0.56 mm)backlash.

3. Loosen bearing adjustment nuts and remove anypreload on bearings.

4. Set up two dial indicators to measure bearing capdeflection (Figure 5-17). Set indicator buttonagainst lock plate mount pads. Zero both indica-tors.

5. Adjust ring and pinion backlash to 0.014 -- 0.018in. (0355 -- 0.457 mm) with adjusting nuts. Checkbacklash at four equal points around ring gear.

6. Tighten both adjusting nuts equally until bearingcaps have deflected a total of 0.005 in. (0.127mm), combined reading from both indicators.

7. Recheck backlash setting and adjust if necessary.

8. Tighten bearing cap capscrews (4, Figure 5-16) to750 ft. lb. (1017 Nm) torque and lock wire.

9. Install lock plates (7) and capscrews (6). Tightento standard torque and lock wire. Lock plates maybe installed in either direction to achieve halfnotch adjustments.

10. Remove from fixture and install differential carrierassembly in final drive.

FIGURE 5-17. RING AND PINION BACKLASHADJUSTMENT

1. Dial Indicators


FINAL DRIVE PLANETARIES AND WHEEL HUBS

PLANETARY DRIVE

Planetary Drive Removal

1. Securely block front wheels, raise and block uprear of truck and remove rear wheels. Refer to"Rear Tire and Rim Removal", this Section.

NOTE: If only disassembly or repair of the planetarydrive is necessary, tires and rims are not required tobe removed. However, the tires and rims must besecured to the frame or final drive case, so that nutsand wheel retainers may be removed for access toplanetary drive.

If wheels are not being removed, rotate assemblybefore securing tires and rims so that drain plug(11, Figure 6-1) is at the bottom. If planetary willnot rotate, proceed as follows to remove sun gear(9).

2. Drain approximately 10 gal. (38 l) of oil from finaldrive case.

3. Remove capscrews (4), cover (6), and O-ring (5).

4. Remove thrust plug (7) and retainer ring (8).

5. Remove sun gear (9), and thrust bushing (2) fromsun gear shaft (3).

6. If not done previously, rotate assembly so thatdrain plug (11) is at the bottom. Remove drainplug and drain remaining oil from planetary.

NOTE: A tool can be made to simplify sun shaft re-moval. Refer to Section "M", Special Tools.

7. Pull sun gear shaft (3).

8. If not done previously, fasten tires and rims andwheel hub securely to the frame or final drive case,so that no outward movement can occur. Removewheel nuts and retainers.

9. Remove all 12 pt. capscrews (13) retaining planetcarrier (1) to wheel hubs. Attach Planetary Assem-bly Loading Fixture, SS1125. Refer to Section "M",Special Tools.

10. Slide planet carrier assembly (1) out on wheelmount studs far enough to enable attachment ofa lifting device.

11. As planet carrier is removed from studs, balancecarrier assembly as planet gears come out of ringgear (10). Do not damage threads on wheel re-tainer studs.

12. If planetary assembly is not to be serviced, storeon wood blocks in a clean area away from workarea. Cover with moisture proof protection.FIGURE 6-1. PLANETARY DRIVE ASSEMBLY

1. Planet Carrier 8. Retaining Ring2. Thrust Bushing 9. Sun Gear3. Sun Gear Shaft 10. Ring Gear4. Capscrew 11. Drain Plug5. O-Ring 12. O-Ring6. Sun Gear Cover 13. Capscrew, 12 pt. head7. Thrust Plug

G06002 4/92 Final Drive Planetaries and Wheel Hubs G6-1

Planetary Reactor And Ring Gear Removal

1. If not done previously, secure wheel hub to frameor final drive case to prevent any outward move-ment when planetary reactor (5, Figure 6-2) isremoved.

2. Cut lock wires and remove retainer capscrews (7),retainer (6), and shims (8).

The planetary reactor and ring gear assemblyweigh an estimated 300 lbs. (136 kg). Support ofassembly is necessary.

3. Attach tool SS0416 with 3 -- SS0414 threaded"L"-bolts into large holes in reactor. Tighten boltsand lift out reactor and ring gear. Move assemblyto a clean work area.

4. Be sure that bearing cone (9) does not slide out.A spacer may be fabricated to install temporarilyin place of the reactor. Minimum dimensions forspacer should be: 2.125 in (54 mm) thick, 10.5 in.(267 mm) O.D., and 9.68 in. (246 mm) I.D. Installshims, retainer plate and capscrews to holdspacer in place.

5. Remove lockwire, capscrews (1) and retainers (2)holding ring gear to reactor. Remove ring gear (4)from reactor (5).

Planetary Reactor And Ring Gear Installation

1. Install ring gear (4, Figure 6-2) on reactor (5).

2. Install capscrews (1) and retainers (2) holding ringgear to reactor. Tighten capscrews to standardtorque and lockwire capscrews.

3. If installed, remove capscrews (7), retainer (6),shims (8) and temporary spacer.

4. Wheel Hub must be in position and bearingsadjusted. Refer to "Wheel Hub and Bearing Instal-lation", this Section.

The planetary reactor and ring gear assemblyweigh an estimated 300 lbs. (136 kg). Support ofassembly is necessary.

5. Attach tool SS0416 with 3 -- SS0414 threadedL-bolts into large holes in reactor. Tighten boltsand lift reactor and ring gear onto splined end ofaxle housing. Remove lifting tool.

6. Install shims (8) [as determined in "Wheel Hub andBearing Installation"], hub retainer (6), and re-tainer capscrews (7). Tighten capscrews to stand-ard torque and lockwire.

FIGURE 6-2. PLANETARY REACTOR AND RING GEAR ASSEMBLY

1. Capscrew 6. Planetary Reactor 2. Ring Gear Retainer Retainer3. Wheel Hub 7. Capscrew4. Ring Gear 8. Shims5. Planetary Reactor 9. Outboard Bearing Cone

G6-2 Final Drive Planetaries and Wheel Hubs G06002 4/92


1. Clean all parts thoroughly in clean solvent andblow dry with shop air. Lightly coat parts with justenough clean oil to prevent rust formation onmachined and bearing surfaces.

2. Check planetary carrier, reactor plate and gearteeth for damage, excessive wear or cracks. In-spect all splines for defects. Use a hard stone toremove any minor burrs.

3. Bushing surfaces, bearing rollers and races mustbe free of defects - no galling, cracks or rough-ness. Bearings must turn freely and smoothly.

4. Inspect all components. Replace any defectiveparts as necessary.

Planetary Drive Installation

1. Install O-ring (12, Figure 6-1) in O-ring groove ofplanetary carrier (1). Lightly cover with clean oil(same as required in planetary).

2. Attach lifting device and position planetary assem-bly on wheel rim retainer studs. Do not damagethreads on wheel retainer studs.

3. Align planet gears to ring gear and slide carrier intowheel hub.

4. Install planetary carrier mounting capscrews (13).Tighten to standard torque.

5. Install drain plug (11).

6. Install sun shaft (3) into differential.

7. Install thrust bushing (2). Replace bushing if widthis less than 1.845 ± 0.005 in. (46.86 ± 0.12mm).

8. Install sun gear (9) and new retainer ring (8).

9. Install thrust plug (7). Replace thrust plug if thick-ness of head is less than 0.500 in. (12.7± 0.12mm).

10. Install sun gear cover (6) and O-ring (5).

11. Tighten cover capscrews (4) to standard torque.

12. If removed, install rear tires and rims and removesupports from under truck.

13. Fill final drive housing at center case fill plug untiloil level is at bottom of fill hole. Oil must flow fromcenter housing out to both planetaries; add oiluntil level is maintained at bottom of fill hole. Allow approximately 15 minutes for a proper fill. A complete fill will require approximately 53 gal.(200 l) of oil. Refer to Lube Chart, Section "P", forproper gear lube oil.

Planet Carrier Disassembly

1. Remove planet pin capscrews (1, Figure 6-3) fromall planet pins.

2. Remove planet pin (3) from carrier.

3. Remove planet gears (2) from carrier. Be preparedto retrieve bearing cones (4), as they are notretained in planet gear after removal from carrier.

4. Remove bearing cups (2, Figure 6-4) and spacer(3) from planet gear.

FIGURE 6-3. PLANETARY CARRIER ASSEMBLY

1. Capscrew 4. Bearing Cone2. Planet Gear 5. Spacer3. Planet Pin 6. O-Ring


Planet Carrier Assembly

1. Inspect planet gear pins and carrier bores fordamage and nominal clearance dimensions.Planet carrier pin bore I.D. to pin O.D. - Both Ends:-0.0005 to + 0.0015 in. (-0.013 to + 0.038 mm) Planet gear bearing bore I.D. to pin O.D. + 0.0005 to + 0.0021 in. (+ 0.013 to + 0.053 mm)

2. Install planet gear bearings in planet gear bore.

Before installing bearing cups, determine correctlocation of cup spacer (3, Figure 6-4). The cupspacer must go into gear bore from side of gearmarked "XX". If no "XX" mark, measure dimensionsA and B. A is longer than B. Stamp XX on A side.

a. If removed, install snap ring (1, Figure 6-4) ingroove of planet gear bore.

b. Install spacer in proper position, install bearingcups (2) as illustrated.

3. Thoroughly clean planet carrier, pins, gears andbearings.

4. Block planetary carrier high enough from worksurface, outside surface down, so planet pinstanding on big end will pass under carrier.

5. Install planet gears (2, Figure 6-3) with bearingcones (4) into carrier.

6. Install O-rings (6) on planet pins (3). Lightly coverpins and O-rings with clean oil as used in plantary.

7. Start planet pins through bearings. A long, guidestud thru capscrew hole of carrier into small endof planet pin will aid in aligning capscrew holes.

8. Pull pins into position.

9. Install capscrews (1) and tighten to standardtorque.

WHEEL HUB AND BEARINGS

Removal

1. Securely block front wheels, raise and block uprear of truck, and remove rear wheels. Refer to"Rear Tire and Rim Removal", this Section.

NOTE: Three retaining brackets (3, Figure 6-5) withcapscrews (14) must be installed (to retain rotatingbrake disc hub and floating ring seals to brake assem-bly) before capscrews (10) can be removed fromwheel hub. Refer to Section "M", Special Tools, forWheel Hub Retaining Brackets and capscrews.

2. Attach lifting device to wheel hub. Take up slackand maintain support.

To prevent weight of wheel hub from pushing offoutboard bearing (1, Figure 6-5) and ring gearreactor, maintain inboard pressure on wheel hubas retainer capscrews are removed.

3. Remove planetary drive and reactor. Refer to"Planetary Drive Removal" and "Planetary ReactorAnd Ring Gear Removal", this Section.

4. Slide off bearing cone (1, Figure 6-5). Removecapscrews (10) holding wheel hub (13) onto brakehub assembly. Retaining brackets (3) must re-main attached to brake hub and brake hous-ing.

FIGURE 6-4. PLANET GEAR AND BEARINGS

1. Snap Ring 3. Spacer2. Bearing Cups


5. Remove wheel hub (13) from axle housing. Re-move bearing cone (12) from axle housing.

6. Remove seal carrier (5) and floating ring seal (4)along with O-ring (6). Discard O-ring.

7. Remove bearing cups (2 & 11).

Installation

1. Clean all mounting surfaces. Install bearing cups(2 & 11, Figure 6-5). Install new O-ring (9) ontowheel hub (13).

2. Install seal carrier (5) with floating ring seal (4):

Floating Ring Seal Installation: Refer to Section "J", "Rear Wet Disc Brake Assembly" for this procedure.

FIGURE 6-5. WHEEL HUB ASSEMBLY AND BRAKE ASSEMBLY

1. Bearing Cone 4. Floating Ring Seal Assy 8. Floating Ring Seal Assy 12. Bearing Cone2. Bearing Cup 5. Seal Carrier 9. O-Ring 13. Wheel Hub3. Hub Retaining Bracket 6. O-Ring 10. Capscrew 14. Capscrews (6) (Special Tool -- 3 req.) 7. Pin 11. Bearing Cup (0.375 UNC x 1.0 in.)


3. Install inboard bearing cone (12) tightly againstseal carrier (5).

NOTE: RETAINING BRACKETS (3, Figure 6-5) mustremain in place until wheel hub and planetary reactorhave been installed. Remove retaining brackets (seestep 8) before bearing adjustment and final tighteningof retainer capscrews (7, Figure 6-6) has been com-pleted.

4. Check outboard bearing cone (1, Figure 6-5) andreactor (5, Figure 6-6) for slip fit on axle housing.

5. Install wheel hub (13, Figure 6-5) with O-ring (9)and bearing cone (1) onto final drive axle housing.

6. Install planetary reactor (5, Figure 6-6) and retainer(6) without shims. Place four equally spaced cap-screws (7) into retainer with two capscrews in ahorizontal position next to the 0.781 in. (19.8 mm)diameter holes (1, Figure 6-7).

7. Install capscrews (10, Figure 6-5). Do not tighten.

8. Remove retaining brackets (3, Figure 6-5) and theircapscrews (14). Save retaining brackets for futureuse. Reinstall capscrews in holes and tighten.

9. Tighten capscrews (10, Figure 6-5) to standardtorque.

10. Tighten the four retainer capscrews (installed instep 6.) to 100 ft. lbs. (135.6 N.m) torque androtate wheel hub a minimum of three revolutions.

11. Tighten same capscrews to 200 ft. lbs. (271.0N.m) and rotate wheel hub (3) revolutions mini-mum.

12. Repeat step 11 as required until capscrew torqueis maintained.

13. Remove the vertically positioned capscrews,loosen the horizontally positioned capscrews,and rotate the wheel hub.

14. Tighten the two remaining capscrews to 15 ft. lbs.(20.3 N.m) torque and rotate the wheel hub aminimum of three revolutions.

15. Tighten the same two capscrews to 30 ft. lbs.(40.7 N.m) torque and rotate the wheel hub aminimum of three revolutions.

16. Tighten the same two capscrews to 30 ft. lbs.(40.7 N.m) torque. Do not rotate wheel hub.

FIGURE 6-6. PLANETARY REACTOR AND RING GEAR ASSEMBLY

1. Capscrew 6. Planetary Reactor 2. Ring Gear Retainer Retainer3. Wheel Hub 7. Capscrew4. Ring Gear 8. Shims5. Planetary Reactor 9. Outboard Bearing Cone


17. Using a depth micrometer, measure and recordthe depth to the end of the axle housing throughthe two holes (1, Figure 6-7) adjacent to the twocapscrews.

18. Average the two measured depths and subtractthe thickness of the retainer (6) [ETCHED ONSURFACE OF RETAINER] from the average depth.

19. Add 0.002 in. (0.05 mm) to the dimension estab-lished in Step 16 and make a shim pack of thisdimension within 0.001 in. (0.025 mm). This willprovide a nominal assembled preload of 0.005 in.(0.127 mm).

NOTE: When assembling shim pack, measure eachshim individually and record each measurement. Se-lect shims which will add up to the required shim packdetermined in Step 17.

EXAMPLE:

Average Depth 0.939 in. (23.850 mm)

Subtract Etched Dim. - 0.875 in. (22.220 mm)

GAP 0.064 in. (1.620 mm)

Add Constant + 0.002 in. (0.050 mm)

Required Shim Pack 0.066 in. (1.670 mm)

20. Install shim pack (8, Figure 6-6) and retainer plate(6) as shown. While rotating wheel hub, tightencapscrews (7) in successive steps as follows:

Tighten all capscrews to 100 ft.lbs. (136 N.m)torque.

Tighten all capscrews to 200 ft.lbs. (271 N.m)torque.

Finally, tighten all capscrews to 300 ± 30 ft. lbs.(406.8 ± 41 N.m) torque.

FIGURE 6-7. MEASURING DEPTH FOR SHIMS

1. Holes for Depth 3. Reactor Retainer Measurement Plate2. Lube Oil Transfer Holes (4)


NOTES


SECTION H

HYDRAIR SUSPENSIONS

INDEX

FRONT SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-2Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-3Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-3Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H2-4

REAR SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-2Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-2Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-3

REAR SUSPENSION SPHERICAL BEARING REPAIRDisassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-4Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-4Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H3-4

OILING AND CHARGING PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-1GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-1EQUIPMENT LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-1HYDRAIR® SERVICE KIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-1

Installation of Charging Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-1Removal of Charging Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-2

SUPPORT BLOCKS FOR OILING AND CHARGING DIMENSIONS . . . . . . . . . . . . H4-2FRONT SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-2

Front Suspension Oiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-2Front Suspension Nitrogen Charging . . . . . . . . . . . . . . . . . . . . . . . . . H4-3

REAR SUSPENSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-4Rear Suspension Oiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H4-4Rear Suspension Nitrogen Charging . . . . . . . . . . . . . . . . . . . . . . . . . . H4-5

OIL AND NITROGEN SPECIFICATIONS CHARTS . . . . . . . . . . . . . . . . . . . . . H4-6

H01007 4/92 Index H1-1

H1-2 Index H01007 4/92

FRONT SUSPENSIONS

The HYDRAIR®II suspensions are hydro-pneumaticcomponents containing oil and nitrogen gas. The oiland gas in the four suspensions carry the gross truckweight less wheels, spindles and final drive assembly.The front suspension cylinders consist of two basiccomponents; a suspension housing attached to thetruck frame and a suspension rod attached to the frontspindle. The front suspension rods also act as kingpinsfor steering the truck.

The HYDRAIR®II suspension cylinder requires onlynormal care when handling as a unit. However, afterbeing disassembled these parts must be handled care-fully to prevent damage to the machined surfaces.Surfaces are machined to extremely close tolerancesand are precisely fitted. All parts must be completelyclean during assembly.

Removal

1. Park unloaded truck on hard level surface. Blockwheels and apply parking brake. Refer to Section‘‘G’’, "Front Tire and Rim", and to "Front Wheel Huband Spindle", to remove front wheel, tire, frontwheel hub, and spindle.

2. Remove clamp and boot from around suspension.

3. Discharge nitrogen pressure from suspension byremoving charging valve guard (5, Figure 2-2) andcharging valve cap (1, Figure 2-1). Turn the charg-ing valve swivel nut (4, small hex) counterclock-wise three full turns to unseat valve seal (DO NOTturn more than three turns). DO NOT TURNLARGE [3/4 in. (19 mm)] HEX (see DANGERbelow). Wearing face mask or goggles, depressvalve stem (3) until all nitrogen pressure has beenrelieved.

Make certain only the swivel nut turns. Turning thecomplete charging valve assembly may result inthe valve assembly being forced out of the suspen-sion by the gas pressure inside.

4. After all nitrogen pressure has been relieved, re-move charging valve assembly (Figure 2-1) anddiscard O-ring (9).

5. Attach lifting device to threaded holes (1, Figure2-2) in suspension housing.

FIGURE 2-1. CHARGING VALVE

1. Valve Cap2. Seal3. Valve Core4. Swivel Nut (Small Hex)5. Rubber Washer6. Valve Body (Large Hex)7. O-Ring8. Valve Stem9. O-Ring

FIGURE 2-2. SUSPENSION REMOVAL/INSTALLATION

1. Threaded Holes 4. Nuts2. Mounting Capscrews 5. Charging Valve3. Washers Guard

H02007 Front Suspensions H2-1

6. Remove suspension mounting capscrews (2),nuts (3) and washers (4).

Suspension weighs approximately 1,062 lbs. (482kg). Be certain that lifting device is of adequatecapacity.

7. Move suspension away from frame. Retract sus-pension rod and install charging valve cap andprotector.

Installation

1. Clean all paint or protective coating from mountingsurface of suspension. Assure that mount sur-faces of suspension and frame are smooth andfree of any oil.

2. Install shear bar in slot on frame suspension mountsurface.

3. Attach lifting device to suspension housing andraise into position on frame.

Suspension weighs approximately 1,062 lbs. (482kg). Be certain that lifting device is of adequatecapacity.

4. Install mount bolts (2), washers (3) and nuts (4,Figure 2-2).

5. Tighten nuts to 750 ± 75 ft. lbs. (1017 ± 101 N.m)torque.

6. Install front spindle, hub, wheel and tire. Refer toSection "G" for installation procedures.

7. After installation of suspension, it will be necessaryto check oil level and charge with nitrogen gas.Refer to "Suspension Oiling and Charging" proce-dure, this section.

8. Install boot and boot clamp on suspension.

FIGURE 2-3. SUSPENSION ASSEMBLY

1. Valve Guard 8. Upper Bearing Retainer2. Drain Plug 9. Capscrews & Washers3. Capscrew 10. Bearing Retainer Cap4. Cap 11. Steel Ball5. Housing 12. Capscrew6. Tube 13. Lower Bearing Retainer7. Upper Bearing 14. O-Rings/Backup Rings

H2-2 Front Suspensions H02007

Disassembly

1. Suspension contains approximately 3.5 gal. (13.25l) of oil.

2. Remove charging valve protector (1, Figure 2-3)charging valve cap and loosen 5/8 in. (16 mm) nut.

3. Depress valve core to be sure all nitrogen is ventedfrom suspension. Use eye protection when vent-ing Nitrogen gas. After all nitrogen pressure hasbeen relieved, remove charging valve assembly(Figure 2-1) and discard O-ring (9).

4. With rod extended fully, remove plug (2, Figure2-3) from bottom of suspension tube and drain oil.

5. Remove capscrews (3), securing cap (4) to hous-ing (5). Remove O-rings and backup rings (14).

6. Two threaded holes are provided in cap for capremoval from housing.

7. Remove cap and tube (6) from housing.

8. Remove upper bearing (7) from upper bearingretainer (8).

9. Remove capscrews and washers (9) securingupper bearing retainer cap (10) to tube, if neces-sary.

10. Remove upper bearing retainer (8), as bearingretainer is removed, two balls (1) can also beremoved.

11. Remove capscrews (12) securing lower bearingretainer (13) to housing.

12. Use puller holes in retainer flange to aid in removingretainer from housing.

13. Remove lower bearing (1, Figure 2-4), step seal (2),rod seal (3) and wiper (4) from lower bearingretainer. Remove O-rings and backup rings fromO.D. of retainer.

Inspection

1. If scratches or scores are found in housing or onsuspension tube, contact your HAULPAK® Dis-tributor.

2. Maximum clearance between new upper bearingand housing is 0.020 in. (0.50 mm).

3. Maximum clearance between new lower bearingto suspension tube is 0.020 in. (0.50 mm).

FIGURE 2-4. LOWER BEARING RETAINER SEALS

1. Lower Bearing 3. Double Lip Rod Seal2. Step Seal and 4. Wiper Step Seal O-Ring

H02007 Front Suspensions H2-3

Assembly

1. Clean all components thoroughly.

2. Lightly coat all O-rings, backup rings, seals andwiper with petroleum jelly or suspension oil.

3. Install O-rings and backup rings (1, Figure 2-5) topilot of suspension cap (2).

4. Install step seal O-ring (3) and step seal (4).Position step seal lip toward bearing of lowerretainer.

5. Install rod seal (6) with lip toward bearing of lowerretainer (Figure 2-5).

6. Install wiper (7) with lip pointing away from bear-ing.

7. Install bearing (8).

8. Install backup rings and O-ring on O.D. of lowerbearing retainer.

9. Install lower retainer (9) into housing. Install wash-ers and capscrews (5). Tighten to standardtorque.

10. If removed, install retainer cap, washer (10) and nutto suspension cap. Tighten nut to 800 ft. lbs.(1084 N.m) torque.

11. Place two 3/4 in. (19 mm) balls (11) in pockets oftube. Install upper bearing retainer.

12. Install retainer cap (12), washers and capscrews(13). Tighten to standard torque.

13. Install upper bearing (14) on upper retainer (18).

14. Insert tube (15) and cap (2) into housing. Installcapscrews (16). Tighten to standard torque.

15. Install plug (17) in bottom of tube. Tighten to 13 ft.lbs. (17.5 N.m) torque.

16. Add 3.5 gal. (13.25 l) of suspension oil thru charg-ing valve hole in cap of suspension.

17. Install charging valve assembly (Figure 2-1) withnew O-ring (9). Tighten 3/4 in. (19 mm) nut ofcharging valve to 16.5 ft. lbs. (22.4 N.m) torque.

18. If new charging valve is used, tighten 5/8 in. (16mm) nut to 10.5 ft. lbs. (14 N.m) torque, loosen,retighten to 10.5 ft. lbs. (14 N.m) torque, loosen,retighten to 4 ft. lbs. (5.5 N.m) torque. If old valveis reused, tighten 5/8 in. (16 mm) nut to 4 ft. lbs.(5.5 N.m) torque.

19. Correct oil level will be established when suspen-sion is mounted on truck. Refer to SuspensionOiling and Charging procedure, this section.

FIGURE 2-5. SUSPENSION ASSEMBLY

1. O-Rings/Backup Rings 10. Washer2. Cap 11. Steel Ball3. Step Seal O-Ring 12. Bearing Retainer Cap4. Step Seal 13. Capscrews & Washers5. Capscrews & Washers 14. Upper Bearing6. Double Lip Rod Seal 15. Tube7. Wiper 16. Capscrews8. Lower Bearing 17. Drain Plug9. Lower Bearing 18. Upper Bearing Retainer Retainer

H2-4 Front Suspensions H02007

REAR SUSPENSIONS

The HYDRAIR® II suspensions are hydro-pneumaticcomponents containing oil and nitrogen gas. The oiland gas in the four suspensions carry the gross truckweight less wheels, spindles and final drive assembly.The rear suspension cylinders consist of two basiccomponents; a suspension housing attached to thetruck frame and a suspension rod attached to the finaldrive center case.

The HYDRAIR® II suspension cylinder requires onlynormal care when handling as a unit. However, afterbeing disassembled these parts must be handled care-fully to prevent damage to the machined surfaces.Surfaces are machined to extremely close tolerancesand are precisely fitted. All parts must be completelyclean during assembly.

Removal

Raising the rear frame of the truck will be required forrear suspension removal and installation. Jacking un-der the hoist cylinder frame mounts is recommended.If jacks are unavailable, the frame can be raised andlowered as required by utilizing the suspension as ajack; charging with nitrogen to raise the frame, andreleasing the nitrogen to lower the frame.

1. Park unloaded truck on hard level surface. Blockwheels and apply parking brake.

2. Raise rear of truck frame to fully extend piston ofsuspension to be removed.

3. With suspension piston fully extended, placeblocks between frame and final drive case bumperpads. Be sure blocks will not shift.

4. Discharge nitrogen pressure from suspension byremoving charging valve guard (1, Figure 3-3) andcharging valve cap (1, Figure 3-1). Turn the charg-ing valve swivel nut (4, small hex) counterclock-wise three full turns to unseat valve seat (DO NOTturn more than three turns). DO NOT TURNLARGE HEX (6), see DANGER below. Wearingface mask or goggles, depress valve stem until allnitrogen pressure has been relieved.

Make certain only the swivel nut turns. Turning thecomplete charging valve assembly may result inthe valve assembly being forced out of the suspen-sion by the gas pressure inside.

5. After all nitrogen pressure has been relieved, becertain that frame is resting solidly on blocks.Remove charging valve assembly (Figure 3-1)from top of rear suspension by unscrewing largehex and discard O-ring (9).

6. Remove suspension mount pin retainer bolts (1,Figure 3-2) and nuts from top and bottom pins.

7. Attach lifting device to suspension. Suspensionweighs approximately 315 lbs.(143 kg).

8. Remove top and bottom mount pins (2, Figure 3-2)and spacers (3) and remove suspension fromtruck.

9. Retract rod and replace charging valve cap andprotector and move suspension to work area.


1. Valve Cap2. Seal3. Valve Core4. Swivel Nut (small hex)5. Rubber Washer6. Valve Body (large hex)7. O-Ring8. Valve Stem9. O-Ring

H03006 Rear Suspensions H3-1

Installation

1. Raise suspension into position with grease fittings(16, Figure 3-3) in housing and lower piston rodmount pointing away from rear of truck.

2. Install upper mount pin (2, Figure 3-2) and spacers(3).

3. Remove charging valve protector (1, Figure 3-3)and valve cap (2). Loosen swivel nut (small hex,3) two turns only.

4. Extend or retract suspension rod. Install lowermount pin (2, Figure 3-2) and spacers (3) betweenfinal drive case and suspension rod mount.

5. Install mount pin retainer bolts and nuts (1).Tighten to standard torque.

6. After installation of suspension it will be necessaryto check oil level and charge with nitrogen gas.Refer to Suspension Oiling and Charging proce-dure, this section.

Disassembly

1. Remove charging valve protector (1, Figure 3-3)and valve cap (2) from charging valve.

2. Loosen swivel nut (small hex, 3) two turns only.Depress valve core and vent all nitrogen.

3. Remove charging valve body [3/4 in. (19 mm) nut](6, Figure 3-1) and discard O-ring (9).

4. The suspension contains approximately 2.75 gal.(10.40 l) of suspension oil. Be prepared to catchthis amount of oil.

5. Remove capscrews and washers (9) securinglower retainer (8) to housing (4).

6. Use puller holes in retainer (8) to aid removal.

7. Remove piston rod tube (14) and upper bearingretainer (6) from housing.

8. Remove bearing (7) from retainer.

9. If necessary, remove capscrews and washers (5)securing bearing retainer (6) to piston rod tube(14). Two steel balls (15) will fall free. Retain these.

10. If scratches or scores are found in housing orsuspension tube, contact your area HAULPAK®

Distributor.

11. Maximum clearance between new bearing andhousing is 0.020 in. (0.50 mm).

12. Maximum clearance between lower retainer andtube is 0.020 in. (0.50 mm).

FIGURE 3-2. REAR SUSPENSION MOUNTING

1. Retainer Bolt 2. Mount Pin And Nut 3. Spacers

H3-2 Rear Suspensions H03006

Assembly

1. Clean all parts thoroughly.

2. Lightly coat all O-rings, backup rings, seals andwipers with petroleum jelly or suspension oil.

3. Install O-ring/back-up ring and step seal (12, Fig-ure 3-4) in seal retainer. Position lip of step sealtoward inside of suspension.

4. Install double lip rod seal (11) in retainer.

5. Install wiper seal (10) in retainer.

6. Install backup rings and O-rings (13) on O.D. ofretainer.

7. If bearing retainer (6) was removed from pistontube (14), install two balls (15) and bearing re-tainer to piston tube. Tighten capscrews to stand-ard torque.

8. Place bearing (7) on retainer (6).

9. Install piston tube and retainer assembly into sus-pension housing (4).

10. Install seal retainer (8) over tube. Tighten cap-screws (9) to standard torque.

11. Pour 2 gal. (7.5 l) of suspension oil into suspensionthrough charging valve hole.

12. Install charging valve (Figure 3-1) using new O-ring(9). Tighten 3/4 in. (19 mm) nut to 16.5 ft. lbs. (22.3N.m) torque.

13. If a new charging valve is used, tighten 5/8 in. (16mm) swivel nut (3, Figure 3-3) to 10.5 ft. lbs. (14N.m), release and retighten to 10.5 ft. lbs. (14N.m) and release, retighten to 4.0 ft. lbs. (5.5N.m). If the old charging valve is reused, tightenswivel nut to 4.0 ft. lbs. (5.5 N.m) torque.

14. Install valve cap (2) and valve guard (1).

FIGURE 3-3. REAR SUSPENSION ASSEMBLY

1. Charging Valve Guard 9. Capscrews & Washers2. Charging Valve Cap 10. Wiper Seal3. Swivel Nut (Small Hex) 11. Double Lip Rod Seal4. Suspension Housing 12. O-Ring/Back-up Ring5. Capscrews & Washers 13. O-Rings/Back-up Rings6. Upper Brng. Retainer 14. Piston Rod Tube7. Upper Bearing 15. Steel Ball8. Lower Seal Retainer 16. Gease Fitting

H03006 Rear Suspensions H3-3

REAR SUSPENSION SPHERICAL BEARING REPAIR

NOTE: If either top or bottom spherical bearings (2,Figure 3-5) are to be replaced with suspensionmounted on truck, be sure truck frame is securelysupported. Refer to Suspension Removal and Installa-tion for procedure. Securely support suspension asbearing is being removed and installed.

Disassembly

1. Remove retaining ring (2, Figure 3-5) from mount-ing eye of housing or tube.

2. Remove bearing (2).

Inspection

1. Inspect mount pin (3), spacers (4) and mountingeye bearing bores for damage. Replace as necessary.

2. Tolerance Dimensions:

Suspension frame and final drive mount pin boresI.D. to mount pin O.D.: + 0.005 in. (0.012 mm) to 0.0035 in. (0.088 mm).

Spherical bearing O.D. to suspension mountbearing bore I.D.: -0.0002 in. (0.005 mm) to + 0.0018 in. (0.045 mm).

Spherical bearing I.D. to mount pin O.D.: -0.0001 in. (0.002 mm) to + 0.0015 (0.038 mm).

Assembly

1. Install spherical bearing (2) in mount eye bore.

2. Install retaining ring (1).

3. Refer to Suspension Installation. Be sure grease isapplied to bearing before operating truck.

4. After suspension is installed on truck, it may benecessary to charge suspension with nitrogen.Refer to Suspension Oiling and Charging proce-dure, this section.

FIGURE 3-4. SPHERICAL BEARING INSTALLATION

1. Retaining Ring 3. Mount Pin2. Spherical Bearing 4. Spacers Assembly

H3-4 Rear Suspensions H03006

OILING AND CHARGING PROCEDURES

GENERAL

These procedures cover Oiling and Charging of HY-DRAIR® II suspensions on HAULPAK® trucks. HY-DRAIR® II suspensions which have been properlycharged will provide improved handling and a betterride while improving truck frame fatigue life and bettertire wear.

NOTE: Inflation pressures and exposed piston lengthsare calculated for a normal truck gross vehicle weight(GVW). Additions to truck weight by adding body lin-ers, tailgates, water tanks, etc. should be consideredpart of the payload. Keeping the truck GVW within thespecification shown on the Grade/Speed chart in theoperator cab will result in a better ride and will extendthe service life of the truck main frame and HYDRAIR®

II suspensions.

All HYDRAIR® II suspensions are charged withcompressed nitrogen gas with sufficient pressureto cause injury or damage if improperly handled.Follow all safety instructions, Cautions, and Warn-ings provided in the following procedures to pre-vent any accidents during Oiling and Charging.

Proper charging of HYDRAIR® II suspensions requiresthat three (3) basic conditions be established in thefollowing order:

1. Oil level must be correct.

2. Suspension piston rod extension for nitrogencharging must be correct and this dimension bemaintained during nitrogen charging.

3. Nitrogen charge pressure must be correct.

For best results, HYDRAIR® II suspensions should becharged in pairs (fronts together and rears together).If rears are to be charged, the fronts should be chargedfirst.

NOTE: Set up dimensions specified in the charts mustbe maintained during oiling and charging procedures.However, after truck has been operated, these dimen-sions may vary.

EQUIPMENT LIST

HYDRAIR® Charging KitJacks and/or Overhead CraneSupport Blocks for Oiling height - FrontSupport Blocks for Nitrogen Charging height- FrontHYDRAIR® Oil (See Specifications Chart)Dry Nitrogen (See Specifications Chart)

HYDRAIR® CHARGING KIT

Assemble service kit as shown in Figure 4-1 and attachto container of pure dry nitrogen (8).

Installation of Charging Kit

1. Remove protective covers and charging valvecaps from suspensions to be charged.

2. Turn "T" handles (1, Figure 4-1) of adapters (2)completely counterclockwise.

FIGURE 4-1. HYDRAIR CHARGING KIT

1. "T" Handle2. Charging Valve Adapter3. Manifold Outlet Valves (from gauge)4. Inlet Valve (to gauge)5. Regulator Valve (Nitrogen Pressure)6. Manifold7. Charging Pressure Gauge (Suspensions)8. Dry Nitrogen Gas (Specifications Chart)

NOTE: Arrangement of parts may vary from illustrationabove, depending on Charging Kit P/N.

H04008 8/96 Oiling and Charging Procedures H4-1140M/210M

3. Be certain outlet valves (3) and inlet valve (4) areclosed (turned completely clockwise).

4. Attach charging valve adapters (2) to each sus-pension charging valve stem.

5. Turn "T" handles (1) clockwise (this will depresscore of charging valve and open gas chamber ofsuspension).

6. Open both outlet valves (3).

By selective opening and closing of outlet valves (3),and inlet valve (4), suspensions may be charged sepa-rately or together.

Removal of Charging Kit

1. Close both outlet valves (3).

2. Turn "T" handles (1) counterclockwise to releasecharging valve cores.

3. Remove charging valve adapters (2) from charg-ing valves.

4. Install charging valve caps and protective coverson both suspensions.

SUPPORT BLOCKS FOR OILING ANDCHARGING DIMENSIONS

Prior to starting oiling and charging procedures, sup-ports should be fabricated which will maintain thecorrect exposed piston rod extensions.

Exposed piston rod extensions are specified for bothoil level and nitrogen charging for HYDRAIR®II sus-pensions. These dimensions are listed in tables belowFigures 4-2 and 4-4. Measure dimensions from face ofcylinder gland to machined surface on spindle or to topof bottom support bracket as shown. Do NOT includecapscrew heads in measurements.

Support blocks may be made in various forms. Mildsteel materials of 0.5 in. (13mm) minimum thickness isrecommended. Square bar stock or pipe segmentsmay be used. Blocks must be capable of supportingthe weight of the truck during oiling and chargingprocedures while avoiding contact with plated surfacesand seals on the suspension.

Refer to Figure 4-2 for front suspension support blockplacement.

As an aid for identification for next use, some opera-tions color code the support blocks to mark them asused for: Truck Model, Oiling, or Charging for Frontor Rear suspensions.

FRONT SUSPENSION

1. Park unloaded truck on a hard level surface. Blockwheels, apply parking brake.

2. Thoroughly clean area around charging valve onthe suspensions. Remove protective covers fromcharging valves.

All HYDRAIR® II suspensions are charged withcompressed nitrogen gas with sufficient pressureto cause injury or damage if improperly handled.Follow all safety notes, cautions and warnings inthese procedures to prevent accidents during serv-icing and charging.

Front Suspension Oiling

When blocks are in place on a suspension, theymust be secured with a strap or other means toinsure the blocks stay in place while being used.An unsecured block could fly loose as weight isapplied, presenting the possibility of serious injuryto nearby personnel and/or damage to the equip-ment.

1. Position and secure oiling height dimensionblocks in place (Figure 4-2) so when nitrogenpressure is released, suspensions will lower toseat on the blocks. Take care that blocks do notmar or scratch plated surface of the piston nordamage the wiper seals in the lower bearing re-tainer. Support blocks must seat on the spindleand the cylinder housing. Place 2 blocks (180o

apart) on each side of suspension to providestability.

Wear a face mask or goggles while relieving nitro-gen pressure.

H4-2 Oiling and Charging Procedures H04008 8/96140M/210M

2. Remove charging valve cap. Turn the chargingvalve swivel nut (4, Figure 4-3) counterclockwisethree full turns to unseat valve. DO NOT TURNLARGE HEX (6). The charging valve body has ableeder groove in its mounting threads but forsafety of all personnel, the valve body must not beloosened until ALL nitrogen pressure has beenvented from the suspension.

3. Depress the charging valve core to release nitro-gen pressure from the suspension. When nitrogenhas been vented to atmosphere, loosen and re-move the charging valve. The suspension shouldhave collapsed slowly and be seated solidly onthe support blocks.

4. Fill the suspension with clean HYDRAIR® oil untilthe cylinder is full to top of charging valve bore.Drip pans should be used and all spillage cleanedfrom outside of suspension.

Allow suspension to stand for at least 15 minutes toclear any trapped nitrogen and/or bubbles from the oil.Add more suspension oil if necessary. Loosely installcharging valve.

Front Suspension Nitrogen Charging

Lifting equipment (crane or hydraulic jacks) mustbe of sufficient capacity to lift the truck weight. Becertain that all personnel are clear of lift areabefore lift is started.

1. With nitrogen charging blocks at hand (Figure4-2), use crane or jacks to raise the truck toprovide clearance for the blocks.

2. Remove oiling blocks and install nitrogen chargingblocks. Secure blocks so they will not fly free.Lower truck frame until the blocks are firmly andsquarely seated between the spindle and the cyl-inder housing.

NOTE: Use caution to prevent damage to plated cylin-der surfaces and oil seals.

3. Install charging valve with new lubricated "O" ring(9, Figure 4-3), use clean HYDRAIR® oil.

4. Tighten valve body (large hex, 6) to 16.5 ft. lbs.(22.4 N.m) torque. The valve swivel nut (smallhex, 4) must be unseated counterclockwise threefull turns.

FIGURE 4-2. FRONT SUSPENSION DIMENSIONS

TRUCK MODEL

SIZE

OILINGHEIGHT

in. (mm)

CHARGINGHEIGHT

in. (mm)

CHARGINGPRESSURE psi (kPa)

140M 2.0 (50.8) 7.88 (200) 335 (2309)

210M 2.0 (50.8) 7.88 (200) 410 (2826)


1. Valve Cap2. Seal3. Valve Core4. Swivel Nut (small hex, 0.625 in.)5. Rubber Washer

6. Valve Body (large hex nut - 0.75 in.)7. O-Ring8. Valve Stem9. O-ring


Dry nitrogen is the only gas approved for use inHYDRAIR® II suspensions. Charging of thesecomponents with oxygen or other gases may resultin an explosion which could cause fatalities, seri-ous injuries and/or major property damage. Use only nitrogen gas meeting the specificationsshown in charts (Figure 4-5).

5. Install HYDRAIR® Charging Kit and bottle of puredry nitrogen. Charge the suspension with nitrogengas to the pressure shown below Figure 4-2. DONOT use an overcharge of nitrogen to lift thesuspension off the blocks.

6. Shut off gas and remove charging kit components.

7. If charging valve is being reused, tighten swivelnut (4, Figure 4-3) to 4 ft. lbs. (5.4 N.m) torque.

8. If a new charging valve is being used, tightenswivel nut to 10.5 ft. lbs. (14.2 N.m) torque, thenloosen and retighten swivel nut to 10.5 ft. lbs.(14.2 N.m) torque. Again loosen swivel nut andretighten to 4 ft. lbs. (5.4 N.m) torque. Replacevalve cap (1) and tighten to 2.5 ft. lbs. (3.3 N.m)torque (finger tight).

9. Replace protective guard over charging valve.

10. Raise truck frame with crane or jacks to releasethe nitrogen charging dimension blocks and re-move these blocks.

The HAULPAK® front suspensions are now ready foroperation. Visually check rod extensions both withtruck loaded and empty. Record extension dimen-sions. Maximum downward travel is indicated by thedirt ring at the base of the piston. Operator commentson steering response and suspension rebound shouldalso be noted.

REAR SUSPENSION

1. Park unloaded truck on a hard, level surface. Blockwheels, apply parking brake.

2. Throughly clean around charging valves on sus-pensions. Remove protective covers from charg-ing valves.

All HYDRAIR® II suspensions are charged withcompressed nitrogen gas with sufficient pressureto cause injury or damage if improperly handled.Follow all safety notes, cautions and warnings inthese procedures to prevent accidents during serv-icing and charging.

Rear Suspension Oiling

Lifting equipment (Crane or Hydraulic Jacks) mustbe of sufficient capacity to lift truck weight. Becertain that all personnel are clear of lift areabefore lift is started.

NOTE: Oiling and nitrogen charging dimensions forthese suspensions must be measured from centerlineof upper rear suspension mount pin to centerline oflower rear suspension mount pin. Support blocks asdescribed for front suspensions cannot be used.

1. Use lifting equipment (crane or hydraulic jacks) toraise truck to establish the dimensions shown inthe chart below Figure 4-4.

Make certain all personnel are clear and supportblocks are secure before relieving nitrogen pres-sure from the suspension. Use a face mask orgoggles when venting nitrogen.


2. Remove charging valve cap (1, Figure 4-3). Turnthe charging valve swivel nut (4) counterclock-wise three full turns to unseat valve seat. DO NOTTURN LARGE HEX (6). The charging valve bodyhas a bleeder groove in its mounting threads butfor safety of all personnel the valve body MUSTNOT be loosened until ALL nitrogen pressure hasbeen vented from the suspension.

3. Depress the charging valve core to release nitro-gen pressure from the suspension.

When nitrogen pressure has been vented to at-mosphere, loosen and remove the charging valve.The suspension should have collapsed slowly asgas pressure was released. Truck weight shouldnow be supported by the crane or jacks.

4. Fill the suspension with clean HYDRAIR® oil untilthe cylinder is full to top of fill plug bore. Drip pansshould be used and all spillage cleaned fromoutside of suspension. Allow suspension to standfor at least 15 minutes to clear any trapped nitro-gen and/or air bubbles from the oil. Add oil ifnecessary. Loosely install charging valve.

Rear Suspension Nitrogen Charging

Lifting equipment (crane or hydraulic jacks) mustbe of sufficient capacity to lift the truck weight. Becertain that all personnel are clear of lift areabefore lift is started.

1. Raise rear of truck with crane or jacks to providedimensions shown in chart below Figure 4-4.

2. Install charging valve with new lubricated "O" ring(9, Figure 4-3). Use clean HYDRAIR® oil.

3. Tighten valve body (large hex, 6) to 16.5 ft. lbs.(22.4 N.m) torque. The valve swivel nut (smallhex, 4) must be unseated counterclockwise threefull turns.

Dry nitrogen is the only gas approved for use inHYDRAIR®II suspensions. Charging of thesecomponents with oxygen or other gases may resultin an explosion which could cause fatalities, seri-ous injuries and/or major property damage. Use only nitrogen gas meeting the specificationsshown in charts (Figure 4-5).

4. Install HYDRAIR® Charging Kit and bottle of puredry nitrogen. Charge the suspensions with nitro-gen gas to the pressure shown below Figure 4-4.DO NOT use an overcharge of nitrogen to lift thesuspensions off of the jacks.

5. Shut off gas and remove charging kit components.

6. If charging valve is being reused, turn swivel valvenut (4, Figure 4-3) clockwise, tighten to 4 ft. lbs.(5.4 N.m) torque. Replace valve cap (1) andtighten to 2.5 ft. lbs. (3.3 N.m) torque (fingertight).

FIGURE 4-4. REAR SUSPENSION DIMENSIONS

TRUCK MODEL

SIZE

OILINGHEIGHT

in. (mm)

CHARGINGHEIGHT

in. (mm)

CHARGINGPRESSURE psi (kPa)

140M 31.6 (803) 34.5 (876) 190 (1310)

210M 31.6 (803) 34.5 (876) 240 (1655)


7. If a new charging valve is being used, tightenswivel nut to 10.5 ft. lbs. (14.2 N.m) torque, thenloosen and retighten swivel nut to 10.5 ft. lbs.(14.2 N.m) torque.

8. Loosen swivel nut again and retighten to 4 ft. lbs.(5.4 N.m) torque. Replace valve cap (1) andtighten to 2.5 ft. lbs. (3.3 N.m) torque (fingertight).

9. Replace protective guard over charging valve.

10. Remove the lifting equipment (crane or hydraulicjacks) from the truck.

The HAULPAK® rear suspensions are now ready foroperation. Visually check piston rod extensions bothwith truck loaded and empty. Record extension dimen-sions. Maximum downward travel is indicated by thedirt ring at the base of the piston. Operator commentson steering and suspension rebound should also benoted.

OIL AND NITROGEN SPECIFICATIONS CHARTS

HYDRAIR® II OIL SPECIFICATIONS

Ambient Temperature Range Part No. Approved Sources

-30°F & above (-34.5°C & above) VJ3911

Mobil 424Mobil D.T.E. 15Texaco TDH Oil

AMOCO ULTIMATEMotor Oil 5W--30

Sunfleet TH Universal Tractor FluidChevron Tractor Hydraulic Fluid

Conoco Power Tran III FluidPetro Canada Duratran Fluid

Shell Canada Donax TDL

-55°F & above (-48.5°C & above) VJ5925Emery 2811, SG-CD,

5W--30Mobil Delvac I, 5W--30

Petro Canada Super Arctic Motor Oil, 0W--30

Conoco High PerformanceSynthetic Motor Oil, 5W--30

NOTE: VJ3911 and VJ5925 oils are not compatible and must not be mixed in a suspension. VJ3911 and VJ5925 oils are supplied in 5 gallon (19 Liter) cans.

NITROGEN GAS (N2) SPECIFICATIONS

Nitrogen gas used in HYDRAIR® IISuspension Cylinders must meet orexceed CGA specification G--10.1 forType 1, Grade F Nitrogen Gas

Property Value

NitrogenWater

Dew PointOxygen

99.9% Minimum32 PPM Maximum

-68°F (-55°C) Maximum0.1% Maximum

FIGURE 4-5. SPECIFICATIONS CHART


SECTION JBRAKE CIRCUIT

BRAKE CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-1CIRCUIT OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-1

Charging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-1Manual Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-1

HYDRAULIC OIL MANIFOLD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-2BRAKE ACCUMULATORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-2ACCUMULATOR PRECHARGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-2LOW-PRESSURE BRAKE DETECTION MODULE . . . . . . . . . . . . . . . . . . . . . . J2-2

Low-Pressure Sensing Shuttle Valve . . . . . . . . . . . . . . . . . . . . . . . . . . J2-2Brake Accumulator Pressure Checks . . . . . . . . . . . . . . . . . . . . . . . . . . J2-2Accumulator Shuttle Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-3Accumulator Discharge Valves (Bleeddown Valves) . . . . . . . . . . . . . . . . . . J2-3Emergency Apply Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-3Brake Pressure Warning Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-3

BRAKE MANIFOLD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-3Brake Lock Shuttle Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-3Brake Lock Solenoid Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-4Brake Manifold Shuttle Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-4Steering Bleeddown Solenoid Valve . . . . . . . . . . . . . . . . . . . . . . . . . . J2-4Steering Accumulator Pressure Check . . . . . . . . . . . . . . . . . . . . . . . . . J2-4

SERVICE BRAKE TREADLE VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-4RETARDER TREADLE VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-4SERVICE BRAKE/RETARDER SHUTTLE VALVE . . . . . . . . . . . . . . . . . . . . . . J2-5STOP LIGHT MANIFOLD AND TEE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-5REAR BRAKE SHUTTLE VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-5WET DISC BRAKE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J2-5

BRAKE CIRCUIT COMPONENT SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-1LOW-PRESSURE BRAKE DETECTION MODULE . . . . . . . . . . . . . . . . . . . . . . J3-1BRAKE MANIFOLD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-1BRAKE ACCUMULATOR REPAIR (Refer To Section "L", Hydraulic System) . . . . . . . J3-2SERVICE BRAKE TREADLE VALVE REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . J3-2

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-2Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-3DISASSEMBLY OF TREADLE VALVE ASSEMBLY . . . . . . . . . . . . . . . . . . . J3-3

Removal of Brake Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-3Brake Valve Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-5

ASSEMBLY OF TREADLE VALVE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . J3-5Brake Valve Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-5Installation of Brake Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-7

ADJUSTMENT FOR MAXIMUM DELIVERY PRESSURE . . . . . . . . . . . . . . . . J3-7BRAKE PEDAL ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-8

SERVICE BRAKE TREADLE PEDAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-10Pedal Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-10Pedal Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-10

J01006 8/90 Brake System Index J1-1

RETARDER TREADLE VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-11Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-11Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-11Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-12Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-12Retarder Treadle Pedal Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . J3-13Retarder Treadle Pedal Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . J3-13

BRAKE CIRCUIT CHECKOUT PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . J4-1CIRCUIT TRACKING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-1INITIAL SYSTEM SET-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-2CHECK OF BRAKE CIRCUIT SHUTTLE VALVES . . . . . . . . . . . . . . . . . . . . . . J4-2BRAKE SYSTEM CHECKOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-3FAILURE MODE CHECKOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-4BRAKE VALVE LEAKAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-4TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-5CHECKOUT DATA SHEET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J4-9

FRONT WHEEL SPEED DISC BRAKES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-1Lining Replacement On Truck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-1

BRAKE CALIPER REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-2Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-2Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-2Piston and Seal Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-2Piston and Seal Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-3

BRAKE CALIPER BENCH TEST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J5-3FRONT BRAKE BLEEDING PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . J5-4FRONT SERVICE BRAKE BURNISHING PROCEDURE . . . . . . . . . . . . . . . . . . J5-4

REAR WET DISC BRAKE ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-2Wet Disc Brake Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-3Brake Piston Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-6Brake Piston Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-6Brake Piston Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-6Floating Ring Seal Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-7Wet Disc Brake Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J6-11

REAR WET DISC BRAKE BLEEDING PROCEDURE . . . . . . . . . . . . . . . . . . . . J6-13REAR BRAKE DISC WEAR INDICATOR . . . . . . . . . . . . . . . . . . . . . . . . . . J6-14

Removal/Installation From One Brake To Another . . . . . . . . . . . . . . . . . . J6-14

PARK BRAKE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-1Removal/Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-1Park Brake Lining Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-1Park Brake Linkage Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-1

PARK BRAKE ACTUATOR ASSEMBLY REPAIR . . . . . . . . . . . . . . . . . . . . . . J7-2Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-2Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-2Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-3Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-3Actuator Spring Pod Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-3Actuator Spring Pod Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-4

PARK BRAKE BURNISHING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J7-4

J1-2 Brake System Index J01006 8/90

BRAKE CIRCUIT

The brake circuit is an all-hydraulic-actuated mineral oilsystem, normally operating at 2750 psi (19.25 MPa)pressure. The manual apply system is controlled by theoperator through the Service Brake Treadle Valve (5,Figure 2-1). The operator can modulate applied pres-sure to the front and rear brakes.

The separate Retarder Treadle Valve (7, Figure 2-1),controls the rear brakes only. This pressure is alsomodulated by the operator.

Two separate circuits; one from the front (right) braketreadle valve/retarder circuit, and one from the rear(left) brake treadle valve circuit, provide a means ofapplying the rear brakes in the event pressure is re-duced or lost in one of the circuits.

The system also features an automatic emergencyapply. If the system pressure decreases to 1650 psi(11.6 MPa) or lower, all four wheel brakes will beapplied automatically. Refer to Hydraulic Schematic,Section "R" for details of circuit operation.

CIRCUIT OPERATION

Charging

When the engine is started with the brake circuit com-pletely bled down, oil from the steering/brake pump(11, Figure 2-1) enters the Oil Manifold (1) and then toeach of two brake circuit accumulators (4). From theaccumulators the oil enters the Low-Pressure BrakeDetection Module (2) and all of its components. Fromthere, the oil enters the brake manifold (6) and itscomponents. The oil then enters the service braketreadle valve (5) and the retarder treadle valve (7).

As brake circuit pressure continues to increase, thesignal from the low pressure sensing shuttle valvereleases the emergency apply valve, blocking theemergency apply pilot signal to the pilot piston of theservice treadle valves, releasing the brakes. When sys-tem pressure reaches approximately 2000 psi (14MPa), the brake pressure warning switch opens, turn-ing off the instrument panel warning light.

Anytime the emergency apply valve is activated, thebrake pedal will move freely through its normal travelwith little or no effort. If the emergency apply valvedeactivates while the pedal is depressed a slight "kick"of the pedal will be felt.

FIGURE 2-1. BRAKE CIRCUIT

1. Hydraulic Oil Manifold 8. Service Brake/Retarder Shuttle Valve2. Low-Pressure Brake Detection Module 9. Wet Disc Brakes3. Accumulator Discharge Valves 10. Stop Light Manifold4. Accumulators (Front and Rear Brakes) 11. Steering/Brake Hydraulic Pump5. Service Brake Treadle Valve 12. Front Brake Calipers6. Brake Manifold 13. Rear Brake Shuttle Valves7. Retarder Treadle Valve (Rear Brakes Only) 14. Tee

J02008 8/90 Brake Circuit J2-1

Manual Application

With the system fully charged, apply pressure from theService Brake Treadle Valve to the brakes can bemodulated from 0 -- 1350 ± 100 psi (0 -- 9.45 ± 0.7 MPa)by depressing the brake pedal. The Retarder TreadleValve can also be modulated from 0 -- 1150 ± 100 psi(0 -- 7.9 ± 0.7 MPa) by depressing the retarder pedal.

HYDRAULIC OIL MANIFOLD

The hydraulic oil manifold (1, Figure 2-1) is used as anoil distribution center for charging the steering andboth brake accumulators. Each of three outlet portshas a check valve that allows oil to flow only to theaccumulator it supplies.

BRAKE ACCUMULATORSThere are two brake accumulators (4, Figure 2-1) in thebrake circuit to supply pressure for emergency opera-tion and during normal application (an additional in-board mounted large accumulator is used for thesteering circuit).

The accumulators are floating piston type with nitrogengas on the top side of piston. The nitrogen gas end ofeach accumulator contains a precharge pressureswitch and charging valve. The outlet port directs oil tothe low-pressure brake detection module (2), and thebrake manifold (6). The accumulators are located onthe back of the right front deck support. The smalleroutboard accumulator supplies pressure to the frontbrakes and also supplies an alternate apply line to therear brakes. The retarder circuit is also supplied fromthis accumulator. The larger (middle) accumulator sup-plies pressure to the rear brakes only. Refer to Section"R", Schematics.

ACCUMULATOR PRECHARGE

When the key switch is first turned on before startingthe engine, the accumulator nitrogen precharge warn-ing light on instrument panel should be "Off". If the lightis "On", the nitrogen charge on both accumulatorsshould be checked; correct precharge is 1050 psi (7.3MPa).

LOW-PRESSURE BRAKE DETECTIONMODULEThe low-pressure brake detection module (2, Figure2-1) is located under the accumulators on the right sideof the truck between the accumulators and the brakemanifold in the brake circuit. Figure 2-2 outlines theinternal circuitry and components.

Low-Pressure Sensing Shuttle Valve

The Low-Pressure Sensing Shuttle Valve (1, Figure 2-2)is a replaceable cartridge spool-type valve that sensespressure from each accumulator. The lower of the twoaccumulator pressures will be directed to the pilot endof the emergency apply valve (5) and brake pressurewarning switch (7). When accumulator pressures areequal, the shuttle is balanced, supplying oil to thecircuits mentioned above.

Brake Accumulator Pressure Checks

Two quick disconnect pressure check points (2 & 6,Figure 2-2) are provided for testing brake accumulatorpressures. Refer to "Brake Circuit Checkout", this sec-tion, for testing procedures.

FIGURE 2-2. LOW-PRESSURE BRAKE DETECTIONMODULE

1. Low-Pressure Sensing Shuttle Valve2. Front Brake Accumulator Pressure Check3. Accumulator Shuttle Valve4. Brake Accumulator Discharge Valves (Manual Bleeddown Valves)5. Emergency Brake Apply Valve - 1650 psi (11.4 MPa)6. Rear Brake Accumulator Pressure Check7. Brake Warning Pressure Switch - 2000 psi (13.8 MPa)

J2-2 Brake Circuit J02008 8/90

Accumulator Shuttle Valve

The accumulator shuttle (3, Figure 2-2) valve is a re-placeable cartridge ball type valve that senses pres-sure from each accumulator. The higher of the twopressures is directed to the supply port of the emer-gency apply valve.

Accumulator Discharge Valves(Manual Bleeddown Valves)

Two accumulator discharge valves (4, Figure 2-2) arelocated on top of the low-pressure detection moduleand are used for draining the brake accumulator(s).The right valve controls the front accumulator; the leftvalve controls the rear accumulator. Turning the valvehandles counterclockwise will allow stored accumula-tor oil pressure to return to tank. Turning the valvesclockwise will close the drains and allow the accumu-lators to charge when the engine is started.

Emergency Apply Valve

The emergency apply valve (5, Figure 2-2) is a replace-able cartridge, spring operated, normally open (N.O.)spool type directional valve. When the pilot pressurefrom the low pressure sensing shuttle valve (1) is higherthan the spring pressure of the emergency apply valve,the valve will be held in the normal operating position(pilot port to brake manifold is blocked).

When the pilot pressure on the spool of the emergencyvalve (5) decreases to approximately 1650 psi (11.5MPa) the spring moves the spool to the open positiondirecting accumulator pressure to the pilot ports of theservice brake treadle valves applying the brakes at allwheels.

Brake Pressure Warning Switch

The brake pressure warning switch (7, Figure 2-2) is anormally closed, double pole, single throw switch lo-cated in the pilot circuit between the low pressuresensing shuttle valve (1) and emergency apply valve(5). If emergency apply pilot pressure decreases to2000 psi (14 MPa) or below, the switch closes, turningon the brake pressure warning light and alarm on theinstrument panel.

BRAKE MANIFOLD

The brake manifold valve (6, Figure 2-1) is mounted tothe service brake treadle valve (5, Figure 2-1). Figure2-3 outlines the internal circuitry and components.

Refer to "Brake Circuit Component Service", this sec-tion, for more information.

Brake Lock Shuttle Valve

The Brake Lock Shuttle Valve (5, Figure 2-3) is locatedbetween the brake lock solenoid (6) and the emer-gency apply valve port (1) from the low-pressure brakedetection module.

• When the brake lock solenoid is energized, accu-mulator oil pressure will shift the shuttle ball toblock the pilot port to the right (front) brake valve.The pilot port to the left brake valve will be openand allow the oil pressure to apply the rear brakesonly.

• When the emergency apply valve is energized,accumulator oil pressure will shift the shuttle ballto block the brake lock pilot port and allow bothpilot ports of the service brake valves to be opento the oil pressure to apply all wheel brakes.

FIGURE 2-3. BRAKE MANIFOLD

1. Emergency Apply Valve Port2. Return to Tank3. Steering Bleeddown Solenoid Valve4. Steering Accumulator Pressure Check5. Brake Lock Shuttle Valve6. Brake Lock Solenoid Valve7. Brake Manifold Shuttle Valve


Brake Lock Solenoid Valve

The brake lock valve (6, Figure 2-3) is a replaceablecartridge, solenoid operated, normally closed (N.C.)directional spool valve. The valve receives a supply ofoil from the accumulator shuttle valve. The solenoid isenergized by the instrument panel mounted brake lockswitch. When energized, the solenoid moves the spool,directing oil to the left pilot through a shuttle valve (5)which then applies the rear brakes. When the solenoidis not energized, the rear brake pilot port is open totank, releasing the rear brakes.

Brake Manifold Shuttle Valve

The brake manifold shuttle valve (7, Figure 2-3) islocated between the two accumulator circuits. It willsense the higher of the two accumulator pressures,allowing oil to pass to the Brake Lock Solenoid Valve.This will act as a pilot when Brake Lock is applied,allowing oil to close shuttle valve (5) in the emergencyapply circuit to the brake treadle valve pilot.

Steering Bleeddown Solenoid Valve

The Steering Bleeddown Solenoid Valve is a replace-able assembly. Refer to "Steering Bleeddown SolenoidValve and Low Steering Pressure Switch", Section "L"for more information.

Steering Accumulator Pressure Check

A quick-disconnect (4, Figure 2-3) is provided forchecking steering accumulator pressure. Refer to"Steering Circuit Test Procedure", Section "L".

SERVICE BRAKE TREADLE VALVEThe Service Brake Treadle Valve (5, Figure 2-1) con-tains two valves for brake application. A single pedaloperates both valves for manual brake application. Theleft valve operates rear brakes only; the right operatesthe front brakes and also supplies an alternate applyline to the rear brakes. Each valve is a pressure modu-lating directional valve made up of two sections; anapply section and a modulating section.

The apply section is either pilot or manually operated.

The modulating section will deliver oil from accumula-tor circuits to brake circuits. When a manual applica-tion is made, the delivery pressure will be modulatedby pedal travel. The delivery pressure will be main-tained as long as the pedal is held at that position.Maximum apply pressure is delivered when the pedalis completely depressed.

Pilot application of treadle valves is available from twosources; the brake lock valve and the emergency applyvalve.

• When the brake lock valve is activated, a pilotsignal enters the pilot section of the left treadlevalve. The pilot piston applies only the rear brakesto maximum brake apply pressure.

• When approximately 1650 psi (11.4 MPa) or lessis sensed by the emergency apply valve, a pilotsignal enters the pilot section of both braketreadle valves and opens both accumulator cir-cuits to supply oil to apply all wheel brakes ataccumulator circuit pressure. The service brake treadle pedal is non-respon-sive when this occurs.

RETARDER TREADLE VALVEThe retarder treadle valve (7, Figure 2-1) is located tothe left of the service brake treadle valve and appliesthe rear brakes only. It is a manually operated pressuremodulating directional valve which delivers oil from thefront brake accumulator circuit to the rear brakes.When an application is made, the delivery pressure willbe modulated by pedal travel. This delivery pressurewill be maintained as long as the pedal is held at thatposition. Maximum apply pressure is 1150 psi (8.05MPa) when the pedal is completely depressed.


SERVICE BRAKE/RETARDER SHUTTLE VALVE

The Service Brake/Retarder Shuttle Valve (8, Figure2-1), is a two way valve mounted under the cab on across member near the brake and retarder treadlevalves. It is located between the service brake treadlevalve and the retarder treadle valve circuit. The purposeof the shuttle valve is to separate the oil flow from eitherthe service brake treadle valve or the retarder treadlevalve from flowing into the other valve.

When the service brake treadle valve is applied, hy-draulic pressure from the small accumulator, throughthe right side brake controller valve will cause theshuttle valve to shift, blocking the flow of oil to theretarder treadle valve, but allowing oil to apply the frontand rear brakes.

When the retarder valve is applied, the shuttle valve willshift to the other side, preventing oil from entering theservice brake treadle valve, but will allow oil from thesame small accumulator circuit to apply the rear brakesonly.

STOP LIGHT MANIFOLD AND TEEA manifold (10, Figure 2-1) is mounted on the final driveanchor structure which contains the stop light pressureswitch. It receives brake apply pressure from the front(right) brake treadle valve/retarder circuit (small brakeaccumulator) and activates the rear stop lights. It alsodistributes the apply pressure to one port of each rearbrake shuttle valve.

A tee (14, Figure 2-1) is mounted above the manifoldand receives brake apply pressure from the rear (left)brake treadle valve and distributes apply pressure tothe other port of each rear brake shuttle valve.

REAR BRAKE SHUTTLE VALVES

A Shuttle Valve (13, Figure 2-1) is mounted at each rearbrake assembly. These shuttle valves normally receivebrake apply pressures from two separate circuits asdescribed above; one from the front (right) braketreadle valve/retarder circuit through the stop lightmanifold, and one from the rear (left) brake treadlevalve circuit and through the tee. Having two separatecircuits provides a means of applying the rear brakesin the event pressure is reduced or lost in one of thecircuits. The shuttle valves will move and close off thelower pressure side and the rear brakes will be appliedthrough the higher pressure line.

WET DISC BRAKE ASSEMBLYA Wet Disc Brake Assembly (9, Figure 2-1) is mountedon both sides of the differential on the final drive hous-ing and inboard from the wheel hub and planetarydrive. The assembly contains a shuttle valve assembly,a splined housing, two damper discs, ten separatorplates, eleven friction discs, a spacer, a piston assem-bly, and a splined rotating hub.

The housing is internally splined to retain the steeldamper and separator discs. The separator discs arealternately placed between the friction faced discswhich are splined to the rotating hub. The inboard sideof the assembly contains the piston assembly which isactivated by hydraulic pressure from either the servicebrake treadle valve or the retarder treadle valve. Ashydraulic pressure is applied, the piston moves andcompresses the rotating friction faced discs against thestationary steel discs. The friction forces generatedresist the rotation of the wheels. As hydraulic pressureincreases, friction forces are increased and wheel ro-tation is slowed until maximum force is reached andthe wheel is stopped.

The complete brake disc pack is cooled by hydraulicoil. The cooling oil circuit is a low-pressure circuit whichis completely separate from the high-pressure pistonapply circuit. The cooling oil flows from the pump,through two 12 micron (absolute) filters, through a heatexchanger, to the brake assembly housing (from theoutside of the housing inward to the rotating hub formaximum cooling) and then to the hydraulic tank.

Dynamic retarding is also provided by the wet discbrakes. The dynamic retarding is used to slow the truckduring normal truck operation or to control speedcoming down a grade. When the operator’s retarderpedal is depresed, front wheel brakes are not used;only the rear wet disc brakes are applied.


NOTES


BRAKE CIRCUIT COMPONENT SERVICE

Before removing any brake lines or brake circuitcomponents, be sure brake accumulators are bleddown. To bleeddown accumulators:



•• Bleed down brake accumulators by turn-ing Accumulator Discharge Valve handlescounterclockwise to open. Wait at least 90seconds to let accumulators bleed down.When brake accumulators are completelybled down, close accumulator dischargevalves by turning handles clockwise.Do not leave open.

LOW PRESSURE BRAKE DETECTIONMODULEThe low-pressure brake detection module ( Figure 3-1)is a serviceable component and is mounted under theaccumulators on the right side of the truck. Refer to"Brake Circuit Checkout", this section, for testing andtroubleshooting this valve and its internal components.All components are individually serviceable withoutremoving the complete module from the truck.

Low-Pressure Sensing Shuttle ValveThe Low-Pressure Sensing Shuttle Valve (7, Figure 3-1)is replaceable as a cartridge assembly.

Accumulator Shuttle ValveThe accumulator shuttle (6, Figure 3-1) valve is replace-able as a cartridge assembly.

Accumulator Discharge Valves (BleeddownValves)The Accumulator Discharge Valves (Manual Bleed-down Valves) are replaceable as a cartridge assem-blies.

Emergency Apply ValveThe emergency apply valve (2, Figure 3-1) is replace-able as a cartridge assembly.

Brake Pressure Warning SwitchThe brake pressure warning switch (11, Figure 3-1) is

a normally closed, double pole, single throw switch andis replaceable as an assembly.

BRAKE MANIFOLD

The brake manifold is mounted to the service braketreadle valves under the cab of the truck. It contains thefollowing components which are individually service-able without removing the complete manifold from thetruck:

•• Steering Bleeddown Solenoid Valve•• Steering Accumulator Pressure Check•• Brake Lock Shuttle Valve•• Brake Lock Solenoid Valve•• Brake Manifold Shuttle Valve

FIGURE 3-1. LOW-PRESSURE BRAKE DETECTIONMODULE

1. Rear Accumulator Discharge Valve (Manual Bleeddown Valve) 2. Emergency Brake Apply Valve - 1650 psi (11.4 MPa) 3. Front Accumulator Discharge Valve (Manual Bleeddown Valve) 4. From Front Brake Accumulator 5. Mounting Capscrew 6. Accumulator Shuttle Valve 7. Low-Pressure Sensing Shuttle Valve 8. Front Brake Accumulator Pressure Check 9. Return to Tank10. Rear Brake Accumulator Pressure Check11. Brake Warning Pressure Switch - 2000 psi (13.8 MPa)12. From Rear Brake Accumulator 13. Manifold Housing

J03011 8/90 Brake Circuit Component Service J3-1

Refer to "Service Brake Treadle Valve" for removal orinstallation.

BRAKE ACCUMULATOR REPAIR

Refer to "Accumulator Repair", Section "L".

SERVICE BRAKE TREADLE VALVEThe Service Brake Treadle Valve Assembly (Figure 3-2)consists of a pedal assembly and two modulating, pilotapplied valves to apply the front and rear brakes of thetruck. The right valve (as assembly is mounted incab) controls the front and rear brakes and the leftvalve controls the rear brakes only. It receives oil sup-ply from the two brake accumulators, allowing thepressure to be modulated from 0 - 1350 psi (0 - 9.3MPa).

The bushing mounted pedal is attached to a base usingtwo threaded studs, which allows the pedal to movewhen depressed by the operator for brake application.

Two trunnion mounted rollers are centered over thetwo piston apply rods. When the pedal is depressed forbrake application, the piston apply rods push the pis-tons in the valve body down, allowing pressurized oilto pass to the front and rear brake assemblies.

Removal

Before removing any brake lines or brake circuitcomponents, be sure brake accumulators are bleddown. To bleeddown accumulators:



FIGURE 3-2. SERVICE BRAKE TREADLE VALVE(As Viewed From Front Of Truck)

1. Pedal 8. Rear Brake Apply Port 2. Roller 9. Capscrews (eight) 3. Snap Ring 10. Plug (two) 4. Threaded Stud 11. Front Brake Apply Port 5. Push Rod Assembly 12. Capscrews (four) 6. Valve Body 13. Pedal Stop 7. Brake Manifold 14. Pin

J3-2 Brake Circuit Component Service J03011 8/90

1. After draining accumulators, indentify and tag allhose and wire connections to brake manifold andservice brake treadle valve assembly for correctinstallation during assembly.

2. Disconnect all hoses and wires from assembly.Cap and plug all hoses and ports to prevent entryof contamination.

3. Support treadle valve assembly. Remove all cap-screws, nuts and washers used to mount treadlevalve assembly to the cab deck. Lower valve andbrake treadle valve as an assembly. Move assem-bly to a clean work area.

Installation

Brake pedal must be properly adjusted and deliv-ery pressure must be checked before placing truckin service. Refer to "Adjustment for Maximum De-livery Pressure" procedure.

1. Position service brake treadle valve assembly ontocab deck. Install capscrews, washers and nutssecuring valve assembly to cab deck. Tightencapscrews to standard torque.

2. Connect wires to solenoids as previously tagged.

3. Uncap and connect hoses to all ports. Tightensecurely to prevent high pressure leakage.

4. Refer to steps 14 and 15, "Brake Circuit CheckoutProcedure", this section.

5. Start engine and allow system to fully charge.Bleed both front and rear brakes. Refer to "BrakeBleeding" procedures, this section.

6. Check brake circuit apply pressures. Refer tosteps 23 -- 27, "Brake Circuit Checkout Proce-dure", this section.

DISASSEMBLY OF TREADLE VALVE ASSEMBLY

Removal of Brake Manifold

1. Before any disassembly and with Treadle ValveAssembly positioned as mounted in cab (pedaltoe pointing up and away), mark both valves andtheir positions on the treadle base plate. Markvalves as Right and Left.

2. Remove the eight capscrews (9, Figure 3-2)mounting treadle valve assembly (6) to brakemanifold (7). Place manifold in a clean work area.

FIGURE 3-3. REMOVING TREADLE ASSEMBLY

1. Capscrews and Washers2. Brake Manifold 3. O-Rings


FIGURE 3-4 . VALVE DISASSEMBLY

1. Boot 3. Pushrod2. Spring

FIGURE 3-5. VALVE DISASSEMBLY

1. Pilot Housing 3. Capscrews2. Modulating Housing 4. O-Ring


1. Pilot Piston 3. O-Rings2. Pilot Housing 4. Back-Up Rings


1. Apply Plunger 4. Modulation Housing2. O-Ring 5. Shims3. Spring


1. Snap Ring 4. Regulating Piston2. Spring Retainer 5. Sleeve3. Snap Ring 6. Spring


NOTE: O-rings (3, Figure 3-3) are placed between thebrake mainfold and treadle valve bodies. Remove anddiscard.

3. Remove threaded studs (4) and pedal (1). Inspectfor worn or damaged parts, particularly pedalbushings.

4. Remove four capscrews (12) and separate valvebodies from pedal assembly.

5. Brake valve(s) can now be serviced.

Brake Valve Disassembly

During servicing, the right and left brake valves shouldbe serviced separately and their components shouldnot be interchanged.

NOTE: During disassembly, do not scratch or marhousing or O-ring grooves.

1. Remove boot (1, Figure 3-4) pushrod (3) andspring (2).

2. Match mark pilot housing (1, Figure 3-5) andmodulation housing (2).

3. Remove capscrews (3) connecting the pilot hous-ing to modulating housing and separate the hous-ings.

4. Push pilot piston (1, Figure 3-6) from pilot hous-ing(2).

5. Remove O-rings (3) and backup rings (4) from pilothousing.

6. Remove apply plunger (1, Figure 3-7) O-ring (2)and spring (3) from the modulation housing (4).Observe shims (5) between spring and plungerand maintain this arrangement.

7. Depress spring retainer (2, Figure 3-8), removesnap ring (1), remove spring retainer.

8. Remove snap ring (3), regulating piston (4), sleeve(5) and spring (6).

9. Remove plug (1, Figure 3-9), guide (4), washer (6)and spring (3).

10. Pull out cage spacer (5) and ball assembly (9).

11. Remove all seals, O-rings and backup rings fromall pieces and discard.

ASSEMBLY OF TREADLE VALVE ASSEMBLY

Brake Valve Assembly

If repair of valve requires replacement of internalcomponents other than seals, test equipment willbe required for proper adjustment of maximumdelivery pressure.

NOTE: In following assembly, do not scratch or marhousing or O-ring grooves.

1. Clean and inspect all parts for wear; replace anydamaged parts. Use all new O-rings and backuprings. Lubricate all parts with clean C-3 hydraulicoil.

2. Install O-ring (2, Figure 3-10) on ball assemblyguide (1). Install ball assembly into housing.


1. Plug 6. Washer2. O-Ring 7. Seal3. Spring 8. Backup Ring4. Guide 9. Ball Assembly5. Cage Spacer


3. Install backup ring (4) on regulating piston towardroll pin (7). Install seal (3) with lip pointing awayfrom roll pin.

4. Install regulating piston (6) inside of regulatingpiston sleeve (5).

5. Place backup ring (8) and O-ring (9) on regulatingpiston sleeve. Backup ring toward shoulder ofsleeve. Install spring (10) and regulating pistonassembly in housing. Retain assembly by install-ing snap ring (1, Figure 3-11).

6. Install backup ring (8, Figure 3-9) toward head ofplug (1). Install seal (7) with lip pointing away fromhead of plug.

7. Place O-ring (2, Figure 3-9) on O.D. of plug (1).

8. Place washer, (6) spring (3) and guide (4) in plug(1).

9. Insert cage (5) into housing. Install plug assemblyin housing.

10. Place washer (2, Figure 3-11) on regulating piston,depress against spring, install snap ring (3).

11. Install O-ring (7) in housing (8).

FIGURE 3-10. VALVE ASSEMBLY

1. Ball Assembly Guide 6. Regulating Piston2. O-Ring 7. Roll Pin3. Seal 8. Backup Ring4. Backup Ring 9. O-Ring5. Reg. Piston Sleeve 10. Spring


1. Snap Ring 5. Shims2. Washer 6. Apply Plunger3. Snap Ring 7. O-Ring4. Spring 8. Housing


1. Pilot Piston 3. O-Rings2. Pilot Housing 4. Back-Up Rings


If no valve components are replaced other thanseals, use same shim pack that came out of applyplunger. If springs or components were replaced,refer to "Adjustment for Maximum Delivery Pres-sure" procedure to determine a new shim pack.

12. Place spring (4) shims (5) and apply plunger (6) inhousing (8).

13. Install backup rings (4, Figure 3-12) and O-rings(3) in bore of pilot housing (2) and on pilot piston(1) as shown.

14. Install pilot piston (1) in housing.

15. Install O-rings (4, Figure 3-13) in pilot housing.Align match marks so pilot port from modulatinghousing (2) matches pilot port of pilot housing (1).

16. Install the capscrews through pilot housing intomodulation housing. Tighten capscrews to 32-37ft. lbs. (43.4-50.2 N.m) torque.

17. Install push rod (3, Figure 3-14), spring (2) andrubber boot (1).

Installation of Brake Manifold

1. Install both brake valves onto treadle assembly.Install capscrews and washers (12, Figure 3-2).Tighten capscrews to 35-40 ft. lbs. (47.5-54.2N.m) torque.

2. Install brake pedal (1), if removed. Install threadedstuds (4). Tighten capscrews to 30-50 ft. lbs.(40.7- 67.8 N.m) torque. Do not over tighten.

3. Brake pedal should travel freely and must beproperly adjusted. Refer to "Brake Pedal Adjust-ment" procedure, this section.

4. Install new O-rings (3, Figure 3-3) between brakevalves and brake manifold (2).

5. Install the eight capscrews (9, Figure 3-2) securingbrake manifold to brake valves. Tighten cap-screws to standard torque.

ADJUSTMENT FOR MAXIMUMDELIVERY PRESSUREIf any valve components other than seals are re-placed, a new shim pack must be determined.

NOTE: A 2250-2400 psi (15.7-16.8 MPa) regulated hy-draulic pressure source is required for this procedure.


1. Pilot Housing 3. Capscrews2. Modulating Housing 4. O-Ring

FIGURE 3-14 . VALVE DISASSEMBLY

1. Boot 3. Pushrod2. Spring


1. Install original shim pack (2, Figure 3-15) betweenspring (4) and plunger (3).

2. Bolt an adapter block (5) and O-rings (7) to modu-lation section of valve. Refer to Section "M" foradapter block.

3. Attach pressure source to supply port (8) and areturn line to return port (6).

4. Using a C-clamp, vise or other means, apply valveso that plunger (3) bottoms on valve section hous-ing.

5. Install a 0-3000 psi (0-21 MPa) pressure gauge indelivery port (1).

6. Direct supply pressure to brake valve. Observepressure in delivery port. Delivery port pressureshould be 1300 -- 1400 psi (9.1 -- 9.8 MPa) for eitherright or left valve. Pressures for both valves mustbe within 100 psi (0.7 MPa) of each other.

7. If delivery pressure is below these ranges, addshims. If delivery pressure is above these ranges,remove shims. Each 0.005 in. (0.127 mm) shim willchange the pressure approximately 100 psi (0.7MPa).

FIGURE 3-15. VALVE PRESSURE ADJUSTMENT

1. Delivery Port 5. Adapter Block2. Shim Pack 6. Return Port3. Plunger 7. O-Ring4. Spring 8. Supply Port


1. Plug 6. Washer2. O-Ring 7. Seal3. Spring 8. Backup Ring4. Guide 9. Ball Assembly5. Cage Spacer


BRAKE PEDAL ADJUSTMENTBrake pedal must be properly adjusted and deliv-ery pressure must be checked before placing truckin service.

1. Remove plug (1, Figure 3-16), spring (3) and guide(4) from both valves. Do not allow parts to becomeintermixed between valves.

NOTE: Pedal free travel must be set if maximum deliv-ery pressure has been adjusted. Approximately 0.094in. (2.4 mm) must be available before piston contactsball assembly with pedal in non-apply position. Thisdistance can be determined by measuring the dis-tance the apply stem moves before the piston contactsthe ball assembly. By removing apply line, the freetravel can be observed and measured through thebrake apply port.

2. Hold the ball (1, Figure 3-17) against the seat (2)of one valve.

3. Depress pedal until internal contact is felt againstball.

4. Through the open brake apply port, measure thedistance the apply stem (3) travels. It should travel0.094 in. (2.4 mm) before contact is felt.

5. To make apply stem adjustment, unlock locknuton stop screw located under heel of brake pedal.Turning the stop screw in will increase the freeplay; turning the stop screw out will decrease thefree play.

6. Repeat Steps 1 through 5 for other valve.

7. Install the plugs, springs, and guides into theirrespective valves.

8. Hold pedal in fully apply position and maintainpedal position. Observe both plungers throughbrake apply ports.

NOTE: When pedal is applied, both plungers mustbottom out together to be sure that full brake pressurewill be achieved.

FIGURE 3-17. BRAKE PEDAL ADJUSTMENT

1. Ball 3. Apply Stem2. Seat


SERVICE BRAKE TREADLE PEDAL

Pedal Disassembly

NOTE: If any components in the service brake treadlepedal are replaced. maximum delivery pressureshould be checked and adjusted. Refer to "ADJUSTMENT FOR MAXIMUM DELIVERYPRESSURE", this section.

1. Separate the pedal (9, Figure 3-18) and base (1)by removing both studs (17) from base.

Thoroughly inspect pedal assembly for worn ordamaged parts. Pay particular attention to thebushings (8). If further disassembly is necessary,continue with pedal disassembly procedures.

2. Loosen the set screw (6), but do not remove.Remove shoulder bolt (7). Trunnion assembly(11) and washers (10) can then be removed.

3. Remove the retaining rings (14) and rollers (13)from pin (12). Remove pin (12) from trunnion (11).

4. Use an arbor press to replace bushings (8) withnew bushings.

5. It is not necessary to loosen or remove cap screw(15) or jam nut (16).

6. Remove the push rod (5), and boots, (4) from mainassembly.

Pedal Assembly

NOTE: During assembly, coat the following parts witha clean multi-purpose grease; push rods (5, Figure3-18), bushing (8), shoulder bolt (7), washers (10), andpin (12).

1. Install new boots (4), push rod (5), in the valveassembly.

2. Insert pin (12) into the trunnion (11). Attach rollers(13) and the retaining rings (14) to both ends ofpin (12).

3. Attach trunnion assembly (11) and washers (10)to pedal (9) using shoulder bolt (7).

NOTE: Shoulder bolt (7) must not be over tightened.Trunnion (11) must be free to move.

4. Tighten set screw (6) locking the shoulder bolt inplace.

5. Use an arbor press to replace bushings (8) withnew bushings.

6. Apply a medium strength Loctite to threads ofstuds (17).

7. Align pedal (9) between ears of base (1) and installstuds (17). Tighten capscrews to 30-50 ft.lbs.(40.7-68 N.m) torque.

FIGURE 3-18. SERVICE BRAKE TREADLE PEDAL ASSEMBLY

1. Base 10. Washer (Two)2. Washer (Four) 11. Trunnion3. Capscrew (Four) 12. Pin4. Rubber Boot (Two) 13. Rollers (Two)5. Push Rod (Two) 14. Retaining Rings (Two)6. Set Screw 15. Capscrew7. Shoulder Bolt 16. Jam Nut8. Bushing (Two) 17. Studs (Two)9. Pedal


RETARDER TREADLE VALVE The retarder treadle valve (Figure 3-19) is a singlemodulating hydraulic valve used to apply rear brakesonly. When the pedal is depressed, the operator canmodulate applied pressure from 0 -- 1150 psi (0 --8.05MPa). Oil from the small brake accumulator will shiftthe service brake treadle valve/retarder shuttle valve(blocking off passage of oil back to the service braketreadle valve) and apply the rear brakes only.

Before removing any brake lines or brake circuitcomponents be sure brake accumulators are bleddown. To bleeddown accumulators:

•• Turn key switch "OFF" and shut down en-gine and wait at least 90 seconds to bleeddown steering accumulator. Rotate steer-ing wheel back and forth; no movementshould occur.


Removal

1. Be certain accumulators have been bleddown.

2. Tag all hydraulic lines and their ports (35, 36, 37,Figure 3-19).

3. Remove and cap hydraulic lines to prevent dirtentry.

4. Support the valve from below cab, and removecapscrews (30) from pedal mounting plate.

5. Carefully remove valve from pedal assembly.

NOTE: Maintain the shim stack as found and removefrom top of apply spring.

6. Shim stack can be reused, if only O-rings andbackup rings are being replaced.

Installation

1. Support valve body and align holes with pedalassembly base. Valve ports (35, 36, 37, Figure3-19) will be facing towards the rear of truck.

2. Place capscrews and washers (30) into valve bodyand tighten to 35-40 ft.lbs. (47.5-54.2 N.m)torque.

3. Uncap hydraulic lines and connect to properports. Tighten securely to prevent leakage.

4. Bleed rear brakes. Refer to "Rear Brake BleedingProcedure", this section.

5. Refer to Step 10. in "Check-out Procedure" forretarder apply pressure setting.

Disassembly

1. Remove ring (1, Figure 3-20) and boot (2) fromhousing (16).

2. Remove piston (3), shim or shims (4) and spring(5) from housing bore. Note the number of shimsbeing removed from housing.

3. Remove O-ring (6) from housing bore.

NOTE: Do not scratch or mar housing bore.

4. Remove retaining ring (7), retainer (8), and retain-ing ring (9) from housing bore.

5. Remove the piston and sleeve assembly (10 &14)from housing bore. Separate piston (14) fromsleeve (10).

6. Remove O-ring (12) and the backup ring (11) fromsleeve (10).

7. Remove spring (15) from the piston (14).

8. Remove cup (13) from the piston (14).

A check ball is located inside the piston (14). Makesure ball is clean and moving freely.

9. Remove plug (26) from the housing (16).

10. Remove O-ring (25), cup (23) and back-up ring(24) from the plug (26).

11. Remove washer (22), spacer (21), spring (20) andguide (19) from the housing bore.

12. Remove valve & ball assembly (18) from the hous-ing bore.

13. Remove O-ring (17) from the valve & ball assembly(18).


FIGURE 3-19. RETARDER TREADLE VALVE

1. Shims 2. O-Ring 3. O-Ring 4. Retaining Ring 5. Piston 6. Sleeve 7. Backup Ring 8. O-Ring 9. Spring10. O-Ring11. Sleeve12. Spring13. Cup14. O-Ring15. Plug16. Backup Ring17. Housing18. Washer19. Guide20. Ball21. Seat22. Guide23. Stem24. Cup25. Pin26. Ball27. Retainer Ring28. Retainer29. Spring30. Capscrew and Washer31. Apply Plunger32. Pin and Retainer Ring33. Pedal34. Stopscrew and Locknut35. Drain Port36. Brake Apply Port37. Accumulator Port


Assembly

1. Install O-ring (17, Figure 3-20) on the valve & ballassembly (18) and insert into the housing bore.Note the direction of valve & ball assembly.

2. Install spacer (21)into the housing bore.

3. Install O-ring (25) on plug (26).

4. Insert back-up ring (24) and cup (23) inside end ofplug (26). Note the order of back-up ring and cup.

5. Install guide (19), spring (20) and washer (22) inplug (26). Place plug in the housing bore.

6. Install cup (13) on piston (14) and insert into sleeve(10). Note direction of piston and sleeve.

7. Install back-up ring (11) and O-ring (12) on sleeve(10).

8. Install spring (15) on the piston (14).

9. Install piston and sleeve assembly (10 & 14) intohousing bore. Note the direction of assembly.

10. Install retaining ring (9),retainer (8), and retainingring (7) in the housing bore.

NOTE: Do not mar or scratch housing bore.

11. Install O-ring (6) into housing bore.

12. Install spring (5), shim or shims (4) and piston (3)in housing bore.

For proper brake pressure setting, install the samenumber of shims that were removed during disas-sembly.

13. Install boot (2) and ring (1) into housing (16).

FIGURE 3-20. RETARDER TREADLE VALVE

1. Ring 14. Piston 2. Boot 15. Spring 3 . Piston 16. Housing 4. Shims (as required) 17. O-Ring 5. Spring 18. Valve & Ball Assembly 6. O-Ring 19. Guide 7. Retaining Ring 20. Spring 8. Retainer 21. Spacer 9. Retaining Ring 22. Washer10 . Sleeve 23. Cup11. Back-up Ring 24. Backup Ring12. O-Ring 25. O-Ring13. Cup 26. Plug


Retarder Treadle Pedal Disassembly

1. Separate the pedal (6, Figure 3-21) and base (11)by removing one E-ring (4) from pin (5) and slidingthe pin from base.

2. Loosen the set screw (2) enough to slide pin (1)from the pedal (6). Do not drop the roller (3) whileremoving pin.

3. It is not necessary to loosen or remove cap screw(9) or locknut (10) from base.

Retarder Treadle Pedal Assembly

NOTE: Lightly coat pins (1 & 5, Figure 3-21) and roller(3) with a clean multi-purpose grease.

1. Align the roller (3) between ears of the pedal (6)and insert pin (1). Note direction of the pin.Grooved end of pin should line up with set screw(2).

2. Tighten set screw (2) so it holds pin (1) in place.

3. Align pedal (6) between the ears of base (11) andinsert pin (5). Install E-ring (4).

4. Assemble pedal assembly and valve assemblyusing cap screws (7) and washers (8). Tightencapscrews to 35-40 ft.lbs. (47.5-54.2 N.m)torque.

FIGURE 3-21. RETARDER TREADLE PEDAL

1. Pin 7. Capscrews2. Set screw 8. Washers3. Roller 9. Capscrew4. E-ring 10. Locknut 5. Pin 11. Base6. Pedal


BRAKE CIRCUIT CHECKOUT PROCEDURE

The brake circuit hydraulic pressure is supplied fromthe steering pump and brake accumulators. Somebrake system problems, such as spongy brakes, slowbrake release, or abnormal operation of the instrumentpanel mounted "Low Brake Pressure" warning light cansometimes be traced to internal leakage of brake com-ponents. If internal leakage is suspected, refer to BrakeCircuit Component Leakage Test.

NOTE: If internal leakage within the steering circuit isexcessive, this also may contribute to problems withinthe brake circuit. Be certain that steering circuit leak-age is not excessive before troubleshooting brakecircuit. For Steering Circuit Test Procedure, refer toSection "L", Hydraulic System.

The steering circuit can be isolated from the brakecircuit by removing the brake supply line from thedistribution manifold to the brake accumulators (seeWARNING). Plug the brake supply lines and cap theport in the distribution manifold.

Hydraulic fluid escaping under pressure can havesufficient force to enter a person’s body by pene-trating the skin and cause serious injury, and pos-sibly death, if proper medical treatment by aphysician familiar with this type of injury is notreceived immediately.

Before disconnecting pressure lines, replacingcomponents in the hydraulic circuits, or installingtest gauges, ALWAYS bleed down hydraulic steer-ing and brake accumulators.

The steering accumulator can be bled down with en-gine shut down, turning key switch "Off", and waiting90 seconds. Confirm the steering pressure is releasedby turning the steering wheel - No front wheel move-ment should occur. Open both bleeddown valves onlow pressure brake detection module to bleed downbrake accumulators.

Before disabling brake circuit, be sure truck wheels areblocked to prevent possible rollaway.

Included as the last page of this Checkout Procedureis a Data Sheet to record the information observedduring the hydraulic brake system checkout proce-dure. The data sheet is designed to be removed, cop-ied, and used during the checkout procedure.

* Steps indicated in this manner should be Recorded on the Data Sheet for reference.

The following equipment will be necessary to properlycheck out the hydraulic brake circuit.

a. Hydraulic schematic, refer to Section "R".

b. Calibrated pressure gauges:

Three 0-5000 psi (0-35 mPa) range.

One 0-2000 psi (0-14 mPa) range.

c. One female quick disconnect and hose longenough to reach from rear brake housing to aclean container.

d. Accumulator charging kit with gauges and drynitrogen.

Circuit "Tracking"

In any hydraulic circuit, it is important that hydrauliclines be connected to the correct ports, connectionsand fittings are free of leaks, valves operate correctly,and in some cases, in a given sequence. The checkingof these points, along with flow, direction, and timingof events in a circuit is referenced as "tracking".

J04008 1/93 Brake Circuit Checkout J4-1

INITIAL SYSTEM SET-UPPrior to checking the brake system, the hydraulic sys-tem must have proper accumulator nitrogen prechargepressure and hydraulic oil must be at normal operatingtemperature. Refer to Section "L" this manual for steer-ing system operation procedures and specifications.Also prior to checking the brake system make sure theparking brake is properly adjusted. Refer to parkingbrake adjustment this section.

With the steering system functioning properly and theparking brake adjusted, proceed as follows:

1. Turn engine and key switch "Off". Wait 90 secondsfor the steering accumulator to bleed down.

2. Open both brake accumulator bleed down valves.Verify nitrogen precharge in each accumulator.Accumulator precharge should be 1050 psi (7.35mPa). Charge accumulators if necessary.

* Record on data sheet.

NOTE: Always allow nitrogen gas temperature to ap-proach ambient temperatures before completing pre-charge procedure. For best results, chargeaccumulator in the ambient temperature conditions inwhich the truck will be operating.

3. Close both accumulator bleeddown valves.

Brake Valve Leakage

4. Install a 5000 psi (35 mPa) gauge onto the righthand quick disconnect on the low pressure brakedetection module.

5. Connect a 5000 psi (35 mPa) gauge to the left handquick disconnect on the low pressure brake de-tection module.

6. Install a 5000 psi (35 mPa) gauge to the quickdisconnect on the left (rear) brake valve of theservice brake treadle.

7. Install a 2000 psi (35 mPa) gauge to the quickdisconnect on the right (front) brake valve of theservice brake treadle.

NOTE: The 5000 psi (35 mPa) gauges attached in steps4 and 5 are measuring front and rear brake accumula-tor pressures.

7. Set park brake.

8. Release brake lock.

9. Start engine and allow accumulators to charge tofull system pressure.


* Record brake accumulator pressure readings ondata sheet.

11. Do not operate any controls for 10 minutes. Recordbrake accumulator pressure again. Maximumpressure drop in 10 minutes should not exceed450 psi (3.1 mPa).

* Record pressure readings on data sheet.

Emergency Brakes

12. At this point, slowly bleed-off pressure from thefront brake accumulator, using the right hand man-ual bleeddown valve. As front accumulator pres-sure reaches 2000 ± 50 psi (14 ± 0.3 mPa), the lowbrake warning light should illuminate and buzzershould sound.

* Record pressure reading on data sheet.

13. Continue slowly bleeding-off pressure from thefront brake accumulator. As front brake accumu-lator reaches 1650 ± 50 psi (11.6 ± 0.3 mPa), theemergency apply valve should activate.

14. Front and rear brakes should be fully appliedholding a steady 1275 to 1425 psi (8.8 to 9.8 mPa).


NOTE: The brakes can only be released by bleedingoff the brake accumulators or establishing a safe work-ing pressure in each brake accumulator circuit.

15. Start engine and charge the system.

16. Shut down engine and repeat steps 12 throught 14bleeding-off the rear brake accumulator using theleft hand manual bleeddown valve. When theemergency trigger pressure is reached, the frontbrakes will be fully applied, holding a steady pres-sure of 1275 to 1425 psi (8.8 to 9.8 mPa).


Brake Lock


18. Cycle brake lock several times to assure crisp shiftof solenoid valve and release of pressure.

J4-2 Brake Circuit Checkout J04008 1/93

19. Apply brake lock and read brake pressures. Frontpressure should be zero, and rear brake pressureshould be 1275 to 1425 psi (8.8 to 9.8 mPa) withbrake lock status light illuminated.

20. Turn off brake lock switch and rear brakes shouldrelease with pressure reducing to 0 psi (0 mPa).


BRAKE SYSTEM - FUNCTIONALService Brakes

NOTE: Unless otherwise instructed, perform the fol-lowing checks with the engine running at half throttle,park brake applied, and brake lock released.

21. Very slowly depress the service brake pedal andcheck circuit tracking. The gauges installed insteps 6 and 7 should begin to rise simultaneously.

22. With the service brake treadle fully applied, brakeapply pressure to both front and rear brakesshould be 1275 to 1425 psi (8.8 to 9.8 mPa).Release service brakes and the gauge readingsshould return to 0 psi (0 mPa).


NOTE: Brake pedal "feel" should be smooth with noabnormal noise or mechanical roughness.

23. Slowly depress brake pedal and check to see thatstop lights come on at 100 ± 5 psi (0.7 ± 0.03 mPa).

* Record pressure on data sheet.

24. Quickly and completely depress the brake pedaland check to see that front and rear brake pres-sures read pressure obtained in step 22 withinapproximately one second and maintain that pres-sure fora minimum of 20 seconds. Release pedaland make sure that each circuit’s pressure is zero.

* Record gauge readings on data sheet.

25. Check to see that all front pads are not tight againstdisc. Pads should be loose and moveable by hand.

26. Check brake pedal free play. Refer to "Brake PedalAdjustment", Brake Circuit Component Service,this section.

Retarder

27. Shut down engine and open both brake accumu-lator bleeddown valves and allow both accumula-tors to bleed down. Close both bleeddown valvesafter pressure in accumulators has been reducedto zero.

28. Remove both 5000 psi (35 mPa) gauges from thelow pressure brake detection module.

29. Install one 5000 psi (35 mPa) gauge onto pressuretap provided on retarder treadle valve.

30. Install one 5000 psi (35 mPa) gauge in the parkbrake circuit at the auxiliary manifold.


32. With engine running at half throttle very slowlydepress the retarder treadle valve and check cir-cuit tracking.

33. Retarder pedal fully depressed brake apply pres-sure to rear brakes should be 1100 to 1200 psi (7.7to 8.4 mPa).


NOTE: The pressure gauges on the service braketreadle valves should remain at 0. If not one of the threeshuttle valves in the circuit may not be functioningproperly.

34. Release the brakes and the brake apply pressurein the retarder circuit should return to 0 psi (0 mPa).


Park Brake

35. With engine running and park brake switch in the"off" position, the park brake should be releasedand the warning light off. Read the pressure on the5000 psi (35 mPa) gauge which was installed withstep 30. Park brake pressure should be 2750 ± 50psi (9.1 ± 0.4 mPa).

* Record pressure on data sheet.

36. Check park brake to make sure there is a gapbetween park brake lining and drum.

* Record gap measurement on data sheet.

NOTE: If park brake is not released, refer to "ParkingBrake Adjustment", this section, and repeat steps 35and 36.


37. Shut down engine and turn off key switch with thepark brake switch in the "OFF" position. The Steer-ing bleeddown circuit is activated, discharging thesteering accumulator and the pump outlet pres-sure which automatically will apply the park brake.

38. Start the engine with the park brake in the "ON"position. The park brake will remain "ON" alongwith the indicator as pressure builds.

39. At low idle, apply the service brakes and slowly shiftthe transmission into forward and/or reversegears. With the park brake switch in the "ON"position forward and/or reverse will be inhibited.

40. Turn the park brake switch "OFF" and forwardand/or reverse gears should function after shiftingthrough neutral.

41. Shut down engine and open both brake accumu-lator bleeddown valves.

42. Remove all pressure gauges from system.

43. Install a 5000 psi (35 mPa) gauge in the quickdisconnects on both rear brake housings.

44. Close both brake accumulator bleeddown valves,start engine and charge system.

45. Apply service brake treadle valve and observepressure at full apply.

46. Apply retarder brake treadle valve and observepressure at full apply.

47. If pressures observed in steps 45 and 46 corre-spond to pressure previously recorded, then op-eration of circuit shuttle valves is correct.

NOTE: Defective shuttle valves may affect circuit track-ing and pressures. Isolating individual valves will aidin locating a malfunction in that particular circuit.

48. If any readings specified in the preceeding proce-dure were not within specifications, the reason(s)for the incorrect pressure(s) must be identified,corrected and checkout again verified. All read-ings must be correct and proper circuit operationpresent before releasing truck for production.

49. Shut down truck and open manual bleeddownvalves on both brake accumulators.

50. Remove all pressure gauges and fittings whichwere installed for brake checkout procedures.


BRAKE CIRCUIT AND SERVICE BRAKE TREADLE VALVE TROUBLESHOOTING

POSSIBLE CAUSES SUGGESTED CORRECTIVE ACTION

TROUBLE: The Service Brakes are Locked

Connections to tank and pressure ports reversed.

Tank line is plugged or restricted.

Brake Lock Valve defective.

Emergency Apply Valve defective.

Correct the plumbing.

Remove restriction.

Replace solenoid valve

Replace valve.

TROUBLE: Both Brake Circuits are Dragging

Tank line has back pressure.

Pedal return stop out of adjustment, residual pressure.

Service Brake Treadle Valve pilot port pressurized.

Insure tank line has no back pressure.

Adjust pedal return stop.

Verify proper operation of emergency apply valve.

TROUBLE: One Brake Circuit is Dragging

There is an obstruction in the dual control treadlesubassembly.

Service Brake Treadle Valve is out of balance.

Actuator piston defective.

Service Brake Treadle Valve is defective.

Remove obstruction.

Adjust balance according to instructions.

Replace actuator piston.

Repair or replace Service Brake Treadle Valve.

TROUBLE: The Brakes are Not Going to Full Pressure

Pedal stop out of adjustment.

Internal malfunction of modulating section of ServiceBrake Treadle Valve.

The supply pressure is low.

Improper shimming inside Service Brake TreadleValve.

Shuttle valve(s) in retarder/rear brake circuit defective.

Adjust pedal stop.

Remove, disassemble, clean, and reassemble ServiceBrake Treadle Valve.

Check pump system and accumulators.

Reshim Service Brake Treadle Valve according to instructions.

Obstruction in shuttle valve. Isolate shuttle valves todetermine defective valve. Disassemble and clean orreplace valve.



TROUBLE: A Low Brake Pressure Warning Occurs When the Brakes are Not Applied

Short in electrical system.

Brake accumulators bleed down.

Low pressure sensing shuttle valve defective.

Check wiring.

Valve Open.

Replace valve.

TROUBLE: A Low Brake Pressure Warning Occurs When Brakes are Applied

There is a leak or other malfunction in one brake circuit.



Inspect brake system.

Replace valve.


TROUBLE: Low Retarder Brake Pressure

Retarder pedal stop out of adjustment.

Internal malfunction of modulating section of retardervalve.

Supply pressure low.

Improper shimming inside retarder valve.


Adjust pedal stop.

Remove, disassemble, clean and reassemble retardercontrol valve.

Check pump system and accumulators.

Reshim retarder valve according to instructions.


TROUBLE: Indication of Excessive Brake Temperature (Warning Light On or Gauge Reading High)

Brakes dragging.

Low oil level in hydraulic tank.

High oil level in hydraulic tank.

Restriction in heat exchanger.

Truck being operated in improper transmission range.

See Trouble/Cause/Action previous page.

Fill hydraulic tank to proper level.

Drain hydraulic tank to proper level.

Repair or replace heat exchanger.

Refer to Grade/Speed Chart and select proper trans-mission operating range.

TROUBLE: Low Pressure Warning Light Not Operating Properly

The bulb is burned out.

The circuit is open.

Pressure switch defective.


Replace the bulb.

Check the wiring.

Replace the pressure switch.

Replace valve.



TROUBLE: Low Pressure Warning Light is On Even Though System Pressure is Proper

Short in electrical system.

Pressure switch is defective.

Check wiring.

Replace pressure switch.

TROUBLE: Low Pressure Warning Light Comes On and Pressure is Low

Accumulator Bleeddown valves open.

Charging circuit is malfunctioning.

Restriction in hydraulic filter(s)/heat exchanger.

The pump is worn.

Close Valves.

Check charging circuit.

Repair or replace hydraulic filter(s)/heat exchanger.

Rebuild or replace pump.

TROUBLE: A Brake Accumulator Bleeds Off Quickly When Supply Pressure is Cut Off

Accumulator bleeddown valve is open.

Accumulator precharge is low.

Leak in one circuit, external or internal.

Malfunction in Service Brake Treadle Valve .

Accumulator check valves leaking.

Check plumbing.

Close valve, check precharge.

Check plumbing; circuit leakage.

Remove, disassemble, clean, reassemble; or replace.

Replace check valve.

TROUBLE: A "Squeal" is Heard When Retarder or Service Brake Treadle Valve is Operated

Rapid operation of controller.

Service Brake Treadle Valve assembly is damaged.

Hydraulic oil is too hot.

Normal.

Replace the Service Brake Treadle Valve assembly.

Check hydraulic system cooling.

TROUBLE: The Output Pressure At Controller is Correct but Brakes are Not Applying

Shuttle valve(s) in Retarder/Brake Circuit defective.

Brake lines are blocked or improperly connected.


Check plumbing.

TROUBLE: The Brake Pressures Drift Excessively While Pedal is Held Steady

Contamination in Service Brake Treadle Valve.

Damage in Service Brake Treadle Valve assembly.

Will require disassembly and cleaning.

Replace Service Brake Treadle Valve assembly.



TROUBLE: Oil is Leaking Around the Pedal Base

Defective seal on the top of treadle valve. Replace the seal.

TROUBLE: Oil is Leaking Between the Service Brake Treadle Valve Body Sections

Service Brake Treadle Valve pilot and modulating sections not bolted tightly together.

Defective O-ring(s) between valve sections and brakemanifold.

Remove mounting plate from valve body and tightencapscrews joining pilot and modulating sections to-gether.

Replace the O-ring(s).

TROUBLE: The Pump Cycles Too Often Or Low Pressure Warning Comes On At Low Engine RPM

Leak in hydraulic system.

Accumulators precharge too high or too low.

Service Brake Treadle Valve plumbed incorrectly.

Internal leakage in Service Brake Treadle Valve assembly.

Pump is worn.

Check hydraulic system for leaks.

Check accumulator precharge.

Correct plumbing.

Replace Service Brake Treadle Valve assembly.

Rebuild or replace pump.

TROUBLE: The Parking Brake is Locked

Parking brake solenoid is de-energized.

Parking brake solenoid coil defective.

Parking brake solenoid valve defective.

Park brake linkage improperly adjusted.

Check power to solenoid.

Replace coil.

Replace solenoid valve.

Adjust park brake linkage according to instructions inservice manual.


HAULPAK® CHECK-OUT PROCEDUREHYDRAULIC BRAKE SYSTEM DATA SHEET

MACHINE MODEL UNIT NUMBER SERIAL NUMBER

I. INITIAL SYSTEM SET-UP

Operate Hydraulic System to obtain normal operating temperature. Refer to Check-out Procedures.

STEP 2 Brake Accumulators charged to 1050 psi (7.3 mPa).

II. SERVICE BRAKE SYSTEM CHECK-OUT

Refer to appropriate Service Manual procedures and Bleed brakes.

Brake Valve Leakage

STEP 10 Front brake accumulator pressure.

Rear brake accumulator pressure.

STEP 11 Front brake accumulator pressure after 10 minutes.

Rear brake accumulator pressure after 10 minutes.

STEP 12 Front accumulatorpressure for warning light.

STEP 14 Front accumulatorpressure for emergency apply.

Front brakes- apply pressure.

Rear brakes- apply pressure.

STEP 16 Rear accumulatorpressure for warning light.

Rear accumulatorpressure for emergency apply.

Front brakes- apply pressure.

Brake Lock

STEP 19 Brake lock applied- front brake circuit.

Brake lock applied- rear brake circuit.

Brake lock off- front brake circuit.

Brake lock off- rear brake circuit.


HAULPAK® CHECK-OUT PROCEDUREHYDRAULIC BRAKE SYSTEM DATA SHEET

(Continued)

Service Brakes

STEP 22 Front brake circuit- full apply.

Rear brake circuit- full apply.

Front brake circuit- pedal released.

Rear brake circuit- pedal released.

STEP 23 Pressure at which stop lights come on.

STEP 24 Front brake pressure within one second.

Rear brake pressure within one second.

Retarder

STEP 33 Retarder circuit- full apply.

Retarder circuit- pedal released.

Park Brake

STEP 35 Park brake circuit- released.

Park brake indicator light off- released.

STEP 36 Gap between park brake lining and drum.

Name of Mechanic or Inspector Doing Check-Out


FRONT WHEEL SPEED DISC BRAKESThe front brakes consist of two brake calipers perwheel. Each caliper has two lining assemblies. Thereare no adjusters in the caliper piston assemblies. Eachbrake caliper has three bleeders. The brake caliperswith the linings, weigh approximately 140 lbs. (63.6 kg).




Lining Replacement On Truck

1. Remove tires. Refer to "Tire Removal", Section "G".

2. Inspect brake linings (1, Figure 5-1) for wear.Linings must be replaced when worn to minimumof 0.100 in. (2.5 mm) from back plate.

3. Observe brake disc wear. Refer to Figure 5-2 formaximum disc wear. To replace brake disc, referto Section "G", Front Wheel Hub Removal.

4. Remove lining retainer capscrews (1, Figure 5-3)and retainer (2) on each side of disc.

5. Pry against linings to force pistons back into cali-per.

6. Remove linings from caliper.

7. After linings have been removed, check wiperseals, they should be soft and pliable. If hard ortorn, caliper must be removed for rebuild.

8. Install new linings.

9. Install retainer (2), apply Loctite 271 to retainercapscrews (1). Tighten capscrews to 170 ft.lbs.(230 N.m) torque.

10. Check that linings move freely between retainers.

11. Install tires. Refer to Section "G" for tire installation.

Before placing truck in production, linings must beburnished. Refer to "Service Brake Burnishing"Procedure.

FIGURE 5-1. DISC BRAKE LININGS

FIGURE 5-2.DISC WEAR SPECIFICATIONS

FIGURE 5-3. BRAKE CALIPER ASSEMBLY

1. Capscrew 3. Bleeder Valve2. Lining Retainer

J05008 8/90 Front Disc Brakes J5-1

BRAKE CALIPER REPAIR

Removal





1. Clean brake caliper and spindle area thoroughlybefore tire removal.

2. Remove tires. Refer to Section "G" for Tire RemovalProcedure.

3. Be sure brake accumulators are bled down. Dis-connect brake line to caliper and plug line toprevent contamination.

4. Remove lining retainer capscrews (1, Figure 5-4)and retainers (2). Remove linings (4).

5. Install a lift eye bolt into retainer capscrew hole.

6. Brake calipers weigh approximately 140 lbs.(63.6 kg). Attach lifting device to eye bolt whichwas previously placed in retainer capscrew hole.Take up slack.

7. Remove caliper mounting capscrews (5).

8. Lift caliper away from disc and take to work bench.

Installation

1. Install caliper without lining onto mounting struc-ture. Tighten mount capscrews (5, Figure 5-4) to1050 ft.lbs. (1424 N.m) torque. Remove eye bolt.

2. Pry pistons back completely into caliper housing.Do not damage dust covers.

3. Install lining assemblies (4) retainers (2) and applyLoctite 271 to retainer capscrews (1). Tighten to170 ft.lbs. (230 N.m) torque.

4. Check that linings move freely in retainers andcaliper assembly.

5. Connect brake lines to brake caliper.

6. Bleed brakes, refer to "Front Brake Bleeding Pro-cedure", this section.

7. Install tires. Refer to "Tire Removal", Section "G".

8. If new linings replaced the old linings, the newlinings must be burnished before placing truckback into service. See "Brake Burnishing Proce-dure" in this section.

Piston And Seal Removal

1. Brake calipers must be removed for Piston andSeal Removal. See "Brake Caliper Repair" for re-moval procedure.

2. Remove cylinder heads (1, Figure 5-5) and pistons(2).

3. Remove O-rings (3), from cylinder heads (1).

4. Remove all wipers (4), O-rings (5) and back uprings (6) from each piston bore of caliper anddiscard.

FIGURE 5-4.BRAKE CALIPER INSTALLATION

1. Capscrew 4. Lining2. Lining Retainer 5. Capscrew3. Bleeder Valve

J5-2 Front Disc Brakes J05008 8/90

Piston and Seal Installation

1. Clean all parts thoroughly and inspect for service-ability.

2. Polish any minor scratches from pistons and cali-per bores.

3. Using new O-rings, backup rings and wipers,lightly coat all parts with clean C-3 hydraulic oil.

4. Install O-rings (5, Figure 5-5), backup rings (6) andwipers (4) into each bore of caliper. Install backuprings toward lining side of seal grooves.

5. Lightly coat pistons (2) with clean C-3 hydraulic oiland install from lining side of bores.

6. Install O-rings (3) on cylinder heads.

7. Install cylinder heads (1) and tighten to 75 ft.lbs.(101 N.m) torque.

8. Install bleeder valves (7), if removed.

BRAKE CALIPER BENCH TESTThe purpose of this test is to be certain that overhaulof the calipers was performed satisfactorily. Any leak-age found during this test must be corrected beforeinstalling on truck.

A hydraulic supply with sufficient volume and pressurecapacity to extend piston assemblies will be necessary.A gauge of 0-2000 psi (0-14MPa) should be placed inthe output line of the hydraulic source.

Fabricate a block to simulate brake disc. Use liningbacking plate as a template. Thickness of test blockshould be 0.625 in. (18.8 mm) thick.

1. Secure brake caliper assembly in vise or otherholding fixture.

2. Install new linings and brake disc block.

Be sure test block is securely retained in caliperhead before applying pressure.

3. Attach hydraulic source to inlet port of caliperassembly.

Oil used in the hydraulic source must be of thesame type as used in the Brake Circuit on theHAULPAK® truck.

4. Bleed air from caliper assembly.

During testing or bleeding procedure, DO NOTallow oil to come into contact with brake linings.

5. Gradually increase hydraulic pressure to 1200 psi(8.4 MPa), observing piston assembly for leakage.

6. Reduce pressure to 0 psi (0 MPa).

7. Repeat Step 5 and 6 three times. If no leakage hasbeen observed, reduce pressure to 0 psi (0 MPa)and disconnect hydraulic source and remove testblock.

FIGURE 5-5. BRAKE CALIPER ASSEMBLY

1. Cylinder Heads 5. O-Rings2. Pistons 6. Backup Rings3. O-Rings 7. Bleeder Valve4. Wipers


8. Use adequate force to pry each piston fully intocaliper housing. Do not damage O-rings, wipers,or backup rings.

9. Install brake calipers on truck. Refer to "Installa-tion" instructions.

FRONT BRAKE BLEEDING PROCEDURE

Hydraulic fluid escaping under pressure can havesufficient force to enter a person’s body by pene-trating the skin and cause serious injury and pos-sibly death if proper medical treatment by aphysician familiar with this injury is not receivedimmediately.

Eye protection such as goggles or a face shieldshould be used while performing the followingprocedures.

1. Start engine and allow brake accumulators tocharge. After accumulators have charged, oper-ate engine at 1000 RPM.

2. Install a hose to top bleeder valve of caliper to drainhydraulic oil into a container.

3. Depress service brake pedal and hold down.

Open bleeder only one turn maximum to preventhose from blowing off bleeder valve and oil spillingonto ground. DO NOT allow oil to come into con-tact with brake linings.

4. Open bleeder valve for one minute or until a clear,steady air-free flow of oil comes from bleederhose.

5. After air-free oil is observed, close bleeder andrelease treadle valve. Remove hose.

6. Repeat above procedure for each caliper.

7. After all calipers are bled, make three completebrake applications by depressing treadle valvedown completely. Be certain the brake lining doesnot bind, and that it works properly. Check forleakage after three applications have been made.

FRONT SERVICE BRAKE BURNISHING PROCEDURE

During normal truck operation, the rear wet disc brakesprovide 70% of the braking effort. Therefore, to burnishthe front brakes, it will be necessary to TEMPORARILYdisconnect the rear wet disc brakes from the ServiceBrake Treadle Valve. The Retarder pedal will still be operative.

Braking effort is seriously reduced without the rearwet disc brakes. Prior to disconnecting rearbrakes, be certain truck body is unloaded and alevel area free of obstacles and other equipment isselected to operate truck while burnishing frontbrakes. Serious injury to personnel and propertydamage may result if these precautions are notfollowed.

1. Park truck in a level area, block wheels and applyparking brake.




2. Bleed down accumulators and disconnect the rearbrake apply line at the left service brake treadlevalve. Refer to Brake Circuit Component Service,this Section, for location of brake apply port.

3. Install an O-ring plug in the left brake apply portof the service brake treadle valve and cap "tee"connection on right service brake treadle valvegoing to the Service Brake/Retarder Shuttle valve.Tighten all caps, plugs and brake lines securely toprevent high pressure leakage.


4. Remove wheel blocks and start engine. Be certaintruck body is unloaded and a level area free ofobstacles and other equipment is selected to op-erate truck while burnishing front brakes. Do notexceed 15 mph (24 kph).

5. Drive truck while applying brakes until disc surfacereaches temperature of 450o - 550oF (232o - 287o).Measure front brake disc temperatures with ahand held pyrometer.

NOTE: During the burnishing procedure, the retarderpedal may be used to apply the rear brakes if safety orother circumstances require quick stoppage of truck.

6. Let discs cool to 200oF (93oC).

7. Repeat Steps 4, 5, and 6 three times to completeburnishing procedure.

8. Repeat Step 1 and bleeddown accumulators.

9. Remove O-ring plug (installed at step 3.) in brakeapply port of left service brake treadle valve andremove cap from "tee" connection on right servicebrake treadle valve. Connect rear brake apply lineto the left service brake treadle valve. Connectbrake apply line going from "tee" on right servicebrake treadle valve to the Service Brake/RetarderShuttle valve. Tighten all brake lines securely toprevent high pressure leakage.

10. Refer to Rear Brake Bleeding Procedures, thisSection, and bleed rear brakes to clear any airtrapped during brake line removal/installation.

11. Be sure ALL steps outlined above have beencompleted before releasing truck for operation.


NOTES


REAR WET DISC BRAKE ASSEMBLYA Wet Disc Brake Assembly is mounted on both sidesof the differential on the final drive housing and inboardfrom the wheel hub and planetary drive. This assemblycontains a splined housing, two damper discs, tenseparator plates, eleven friction discs, a spacer, apiston assembly, and a splined rotating hub.

The housing is internally splined to retain the steeldamper and separator discs. The separator discs arealternately placed between the friction faced discswhich are splined to the rotating hub. The inboard sideof the assembly contains the piston assembly which isactivated by hydraulic pressure from either the servicebrake treadle valve or the retarder treadle valve. Ashydraulic pressure is applied, the piston moves andcompresses the rotating friction faced discs against thestationary steel discs. The friction forces generatedresist the rotation of the wheels. As hydraulic pressureincreases, friction forces are increased and wheel ro-tation is slowed until maximum force is reached andthe wheel is stopped.

The complete brake disc pack is cooled by hydraulicoil. The cooling oil circuit is a low-pressure circuit whichis completely separate from the high-pressure pistonapply circuit. The cooling oil flows from the pump,through two 12 micron (absolute) filters, through a heatexchanger, to the brake assembly housing (from theoutside of the housing inward to the rotating hub formaximum cooling) and then to the hydraulic tank.

Dynamic retarding is also provided by the wet discbrakes. When the operator’s retarder pedal is depre-sed, front wheel brakes are not used; only the rear wetdisc brakes are applied. The dynamic retarding is usedto slow the truck during normal truck operation or tocontrol speed coming down a grade.

WET DISC BRAKE ASSEMBLY

Removal





1. Remove rear wheels and tires, planetary drive, andwheel hubs. Refer to Section "G", Drive Axle, Spin-dles and Wheels.

WET DISC BRAKE ASSEMBLY

J06008 9/90 Rear Wet Disc Brake Assembly J6-1

2. Install retaining brackets and capscrews (1, Figure6-1), if not previously installed. Refer to SpecialTools, Section "M" for bracket description. Re-move seal carrier (11, Figure 6-1) and floating ringseal (12), if not previously removed after wheelhub removal.

3. To prevent hydraulic oil from siphoning from tank,loosen the plug above the return tube in the topcover of the hydraulic tank. Refer to HydraulicTank, Section "L". Remove one of two drain plugs(2) to drain excess oil into container.

4. Punch-mark final drive housing and brake assem-bly housing to aid in proper positioning duringassembly.

5. Remove capscrews holding lower cooling-oil line(inlet), upper cooling-oil line (outlet) and rearbrake shuttle valve to brake housing. Cap/plug allopen lines and ports to prevent contamination.

Brake Assembly weighs approximately 1200 lbs.(545 kg.). Use adequate lifting devices.

6. Install lifting device and take up slack. Removecapscrews (6) and carefully slide brake assemblyoff of final drive housing.

7. Move assembly to a clean, dry working area. Placeon wooden blocks for disassembly/storage.

Installation

1. Inspect and clean brake mounting surface (4,Figure 6-1), particularly around O-ring (5) sealingsurface. If O-ring sealing surface is nicked orscratched, repair area before installing brake as-sembly.

2. Install O-ring (5) into brake assembly.

3. Attach lifting device (see WARNING above) andlift assembly into position. Slide onto final drivemounting surface, taking care not to damageO-ring.

4. Position housing assembly so match-marks lineup and hydraulic ports are in correct position.Install capscrews (6). Tighten capscrews tostandard torque.

5. Remove caps and plugs from lines and ports andinstall new O-rings on fittings. Connect lower cool-ing-oil line (inlet), upper cooling-oil line (outlet)and rear brake shuttle valve to brake housing.Tighten capscrews to standard torque.Tightenplug above the return tube in the top cover of thehydraulic tank.

6. Inspect floating ring seal (12). Replace if nicked orscratched . Refer to "Floating Ring Seal Assembly/Installation", this Section.

FIGURE 6-1. WET DISC BRAKE ASSEMBLY

1. Retaining Bracket & 6. Capscrew Capscrews 7. Floating Ring Seal2. Drain Plug 8. O-Ring3. Cooling Oil Port 9. Pin 4. Axle Housing Mount 10. O-Ring Surface 11. Seal Carrier5. O-Ring 12. Floating Ring Seal

J6-2 Rear Wet Disc Brake Assembly J06008 9/90

7. Install O-ring (10) and pin (9) into seal carrier (11).Slide carrier onto housing. Pin must engage intoslot of case structure. To determine correct pinengagement, measure distance from face of sealstructure to face of housing (Figure 6-2). Dimen-sion should be 16.06 ± 0.06 in. (40.79 ± 0.15 cm).

8. Refer to Section "G", for installation of Wheel Hub,Planetary Drive, Wheels and Tires.

NOTE: If new seal rings were installed in oil brakehousing, truck speed must not exceed 25 MPH (40KPH) during the first 4 hours of operation. See "Break-In Procedure" CAUTION decal in cab.

Wet Disc Brake Disassembly

1. Disassemble rear brake assembly in a clean anddry work area. Match mark all components.

2. Place assembly (Figure 6-3), piston (1) side up andhub (8) down on wooden blocking.

FIGURE 6-3. WET DISC BRAKE ASSEMBLY

1. Piston Assembly 5. Damper 9. Floating Ring Seal Assembly2. Brake Housing 6. Retaining Bracket & Capscrews 10. Spacer3. Damper 7. O-Ring Seal Bore 11. Capscrews 4. Disc Pack 8. Rotating Hub

FIGURE 6-2. SEAL CARRIER DIMENSION


3. Remove capscrews (11, Figure 6-3) and install twothreaded eyebolts (1, Figure 6-4) for lifting.

4. Attach lifting device and lift piston assembly (2)out. Set off to one side on wood blocks or work-bench.

5. Remove disc pack (1, Figure 6-5) and spacer (2).Note the order of pack assembly. Place pack offto one side for cleaning and further inspection.

FIGURE 6-5. DISC PACK REMOVAL/INSTALLATION

1. Disc Pack 3. Housing 5. Retaining Brackets and Capscrews2. Spacer 4. Rotating Hub

FIGURE 6-4. PISTON REMOVAL/INSTALLATION

1. Eyebolt 4. Retaining Bracket & Capscrews 7. Disc Pack2. Piston Assembly 5. O-Ring Seal Bore 8. O-Ring3. Brake Housing 6. Rotating Hub 9. Capscrews


6. Lift brake housing and invert housing so hub (2,Figure 6-6) is facing up. Remove capscrews (7)holding the three retaining brackets (6).

7. Attach lifting device to hub and lift hub and ringseal (3) away from brake housing (5). Be carefulnot to damage ring seal (4).

8. Inspect seals (3 & 4). Clean mounting areas andseals thoroughly. If any damage is found, sealassembly must be replaced. Install new sealsaccording to "Floating Ring Seal Installation", thissection.

FIGURE 6-6. HUB AND BRAKE HOUSING ASSEMBLY

1. O-Ring Bore 4. Floating Ring Seal 6. Retaining Bracket 2. Rotating Hub 5. Brake Housing 7. Capscrews3. Floating Ring Seal


Brake Piston Disassembly

1. Position piston with hydraulic ports (6, Figure 6-7)down, onto a wooden or padded work area.

2. Remove eight capscrews(1), springs (3) andspring guides (2). Separate piston (4) from pistonhousing.

3. Remove seal rings and O-rings (8 & 9) and discard.

Brake Piston Inspection

The work area must be clean! All parts must becarefully handled so that no damage occurs topolished sealing surfaces.

1. Check housing bore (5, Figure 6-7) to be sure thatno nicks or scratches are present. If nicks orscratches cannot be removed by polishing, re-place piston housing.

NOTE: Inboard and outboard O-ring grooves are dif-ferent diameters.

2. Inspect piston seal ring grooves for any nicks orscratches. If nicks or scratches cannot be re-moved by polishing, replace piston.

3. Check piston return springs for wear as follows:

Wire Size: 0.177 ± 0.001 in. (4.50 ± 0.025 mm)Coil I.D.: 0.646 ± 0.020 in. (16.40 ± 0.508 mm)Coil O.D.: 1.00 ± 0.020 in. (25.40 ± 0.508 mm)Total Number of Coils: 9.93Free Length: 2.825 in. ± 0.283 in. (71.75 ± 7.20 mm)Working Length Under Load:2.380 in. (60.45 mm) @ 142 ± 14 lbs. (64.5 ± 6 kg)1.758 in. (44.7 mm) @ 340 ± 34 lbs. (154 ± 15 kg)

Replace springs if they do not meet specifications.Weak springs may not allow complete return ofthe piston, causing rapid wear of the brake discsand overheating of hydraulic oil.

Brake Piston Assembly

1. Install O-rings (8 & 9, Figure 6-7) into grooves ofpiston (4), then insert seal rings (see detail # 9).Using fingers or a smooth, rounded object, workseal assembly into piston grooves. Do not nick orscratch seal ring.

2. Lubricate piston and O-ring/seal ring assemblywith clean C-3 hydraulic oil.

3. Lubricate housing bore (5) with clean C-3 hydrau-lic oil. Install two equally spaced 6.0 " long x 3/8"- 16NC guide studs in piston return spring holesto properly position piston.

FIGURE 6-7. PISTON ASSEMBLY

1. Capscrews with Washers 4. Piston 7. O-Ring2. Spring Guide 5. Piston Housing Bore 8. O-Ring/Seal Ring (see detail # 9)3. Spring 6. Apply Port 9. O-Ring/Seal Ring


4. Place piston carefully (O-ring side down) intopiston housing. Align holes of piston with guidestuds in the housing. Firmly tap piston into hous-ing (using nonmetallic mallet) until seated or bot-tomed out. Remove guide studs.

5. Assemble spring guides (2, Figure 6-7) intosprings (3). Apply LOCTITE to threads of 3/8-16NC capscrews with washers (1). Insert cap-screws/washers into spring assemblies and placeinto guide holes of piston and piston housing.Tighten capscrews to standard torque.

6. Pressure check piston assembly by attaching aclean, C-3 hydraulic oil supply to one apply port(6) and a pressure gauge to the other. Apply 100psi. (0.69MPa) of hydraulic pressure. Check forleaks and proper operation of piston before finalassembly.

Floating Ring Seal Assembly/Installation

Failures are usually caused by combinations of factorsrather than one single cause, but many failures haveone common denominator: -- ASSEMBLY ERROR!

Floating ring seals should ALWAYS be installed inMATCHED pairs: that is, two new rings OR two ringsthat have previously run together. NEVER assembleone new ring and one used ring; or two used rings thathave not previously run together. ALWAYS USE NEW TORIC RINGS!!

1. Inspect seal surfaces and mounting cavities forrough tool marks or nicks that may damage rub-ber seal rings. Hone smooth and clean, if required.Remove any oil, dust, protective coating or otherforeign matter from the metal seal rings, the toricrings, and both the housing and seal ring ramps.Use tri-chloroethane # 111 which is a non-petro-leum base, rapid drying solvent leaving no film.Allow surfaces to dry completely. Use clean, lint-free material such as "Micro-Wipes # 05310" forcleaning and wiping.

When using tri-chloroethane or any solvent, avoidprolonged skin contact. Use solvents only in wellvetilated areas and use approved respirators toavoid breathing fumes. Do not use near open flameor welding operations or other heated surfacesexceeding 900°F (482°C). Do not smoke aroundsolvents.

Both ramps must be dry. Use clean, lint-freecloths or lint-free paper towels for wiping.

NOTE: Oil from adjacent bearing installations or sealring face lubrication MUST NOT get on the ramp ortoric until after both seal rings are together in theirfinal assembled postion.

2. Install the rubber toric on the seal ring.

FIGURE 6- 8. FLOATING RING SEAL TERMINOLOGY

1. Seal Ring 6. Seal Ring Face2. Rubber Toric 7. Seal Ring Ramp3. Housing Retainer Lip 8. Seal Ring Retainer Lip4. Housing Ramp 9. Installation Tool5. Seal Ring Housing


Make sure it is STRAIGHT! Make sure the toricring is not twisted and that it is seated againstthe retaining lip of the seal ring ramp. Use the flashline as a reference guide to eliminate twist.Theflash line should be straight and uniform aroundthe toric.

NOTE: Handle seal carefully; nicks and scratcheson the seal ring face cause leaks.

3. Place installation tool onto seal ring with toric.Refer to Special Tools, Section "M" for installationtool. Lower the rings into a container of tri-chlo-roethane until all surfaces of toric ring are wet.

ALTERNATE PROCEDURE:After positioning the seal squarely over the retain-ing lip, thoroughly lubricate the ring by sprayingwith tri-chloroethane # 111.

DO NOT USE Stanosol or any other liquid thatleaves an oily film or does not evaporate quickly.

4. With all surfaces of toric ring wet, use installationtool to position seal ring and toric ring squarelyagainst the seal housing.

APPLY SUDDEN AND EVEN PRESSURE to pop(push) toric under housing retaining lip.

5. CHECK WITH SIGHT GAGE. Check variation inseal ring "assembled height" in four places, 90°apart. Height variation around the assembled ringshould not exceed 0.51 ± 0.05 in. (1.30 ± 0.01mm) for brake assembly floating seal or 0.45± 0.04 in. (1.14 ± 0.01 mm) for the wheel hub seal.

6. If small adjustments are necessary, DO NOTPUSH DIRECTLY ON THE SEAL RING. Makeany required adjustments with installation tool.

7. Toric can twist if it is dry on one spot or if there areburrs or fins on the housing retaining lip.

A bulging toric or cocked seal can contribute toeventual failure.

NOTE: Toric ring must not slip on ramps of either sealring or housing. To prevent slippage, -- WAIT -- at leasttwo minutes. Let all tri-chloroethane evaporate beforefurther assembly. Once correctly in place, the toric ringmust roll on the ramps only. If correct installation isnot obvious, repeat steps 3 through 6.

CORRECT ASSEMBLY


8. Wipe the polished metal seal surfaces with cleantri-chloroethane to remove any foreign material orfingerprints. No foreign particles of any kindshould be on the seal ring faces.

Something as small as a paper towel raveling willhold the seal faces apart and cause leakage.

9. Apply a thin film of clean oil on the seal faces. Usean lint-free applicator or a clean finger to distributethe oil evenly. Make sure no oil comes in contactwith the rubber toric rings or their mating surfaces.

Before assembling both seals & housing together-- WAIT -- at least two minutes. Let all tri-chlo-roethane evaporate. (Some may still be trappedbetween toric and housing ramp.)

10. Be certain both housings are in correct alignmentand are square and concentric. Move the partsslowly and carefully toward each other.

NOTE: Do not slam, bump or drop seals together. Highimpact can damage the seal face and cause leakage.

MAKE SURE SEALS ARE SQUARE

and CONCENTRIC.

INCORRECT ASSEMBLIES


•• A wet spot between housingand ramp can cause slidingand cock the seal.

•• Cocked seals cause unevenpresure on the seal face andmay cause seal to wobble.

•• Uneven pressure causesleakage or scoring.

•• Wobbling seals can cause dirtentry problems in the field.

Wet Spot Slippage

RESULTS OF INCORRECT ASSEMBLY

Points "A" & "B" Remain Stationary

ORIGINAL POSITION "AS ASSEMBLED"

Points "X" & "Y" Rotate 180°

This causes highpressure at "A""Y" and

possible galling.

Whereas at "B""X" there islow pressure andpossible leakage.

ROTATED 180° FROM "ORIGINAL POSITION"


Wet Disc Brake Assembly

1. Position hub (2, Figure 6-9) and brake housing (5)each with seal cavity (3 & 4) facing up. Clean sealcavities and inspect for any damage.

2. If no damage is found in seal cavity refer to"Floating Ring Seal Installation" procedure andinstall new seal halves (3 & 4).

3. After seals have been properly installed, attachlifting device to hub (2) and position over housing(5). Very carefully lower hub into housing. Do notdamage the seal or surfaces. Align the drilledholes in the hub with the three raised bracket padson housing.

4. Secure retaining brackets (6) to hub (2) and hous-ing (5) with capscrews (7). Tighten capscrews tostandard torque.

The three brackets are for TEMPORARY USE ONLYwhile assembling and installing the Wet Disc BrakeAssembly. They must be removed before finalwheel bearing adjustment takes place.

5. Invert the housing and hub assembly with the hubside facing down (4, Figure 6-10). Position the hubmounting surface on wood blocks.

FIGURE 6-9. HUB AND BRAKE HOUSING ASSEMBLY

1. O-Ring Bore 4. Floating Ring Seal 6. Retaining Bracket 2. Rotating Hub 5. Brake Housing 7. Capscrews3. Floating Ring Seal

FIGURE 6-10. DISC PACK REMOVAL/INSTALLATION

1. Disc Pack 4. Rotating Hub2. Spacer 5. Retaining Brackets3. Housing and Capscrews


6. Prior to assembling disc pack, wipe each plate witha lint-free cloth. Inspect and measure all dampers,separator plates, friction discs and spacer forwear or damage. If any damage is found or if apart does not meet specifications, replace part.

Plate Measurements are:

Quantity Description New Plate Thickness

2 Dampers 0.272 ± 0.020 in. (6.9 ± 0.5 mm)

10 Separator Plates

0.094 ± 0.004 in. (2.4 ± 0.1 mm)

11 Friction Discs

0.200 ± 0.005 in.(5.08 ± 0.13 mm)

1 Spacer 0.438 ± 0.005 in.(11.13 ± 0.13 mm)

7. Place spacer (2) into the brake housing (3). It isnot included in the disc pack measurement.

8. Assemble disc pack in a clean, dry area away frombrake housing. Using two wooden blocks of equalthickness and of suitable length to support thedisc pack during measurement, assemble theplates as follows:

1 -- Damper - Cork material facing down.(Unfaced steel side always faces friction disc.)

1 -- Friction disc (internal splines)1 -- Separator plate (external splines)

Continue to alternate friction discs and separatorplates until all eleven friction discs and ten sepa-rator plates are used; finish with:

1 -- Damper - Cork material facing up.(Unfaced steel side always faces friction disc.)

9. Disc pack must be compressed using a minimumof 50 lbs. (22.7 kg) of weight distributed evenlyover disc pack. Keep weight applied during meas-urement of disc pack thickness (step 10).

10. Using a 3" - 4" micrometer, take three measure-ments on the outside edge of disc stack, in equallyspaced locations. Record each measurement andaverage the three readings. The total disc packaverage thickness must be between 3.720 in.(94.50 mm) minimum and 3.819 in. (97.00 mm)maximum.

•• If average thickness is less than 3.720 in. (94.50mm.), an additional separator plate will be re-quired during assembly (see NOTE below).

•• If average thickness is greater than 3.819 in.(97.00 mm), check individual plates for correctquantity and thickness (step 6).

NOTE: If an extra separator plate is required, placeextra separator plate in the brake housing between thespacer and first damper.

11. When disc pack stacked dimension has beendetermined, place discs into brake housing in thesame order as stated in step 8 (spacer shouldhave been placed in housing previously). Be cer-tain that first damper has cork side facingspacer and last damper has cork side facingpiston; unfaced steel side always faces frictiondisc.


12. Attach lifting device to the assembled piston as-sembly (2, Figure 6-11) making sure new O-ring(8) is in place and lubricated with clean C-3 hy-draulic oil. Position piston assembly over housing(3) and align match marks. Lower piston assem-bly into housing.

13. Install capscrews (9) securing piston assembly tohousing. Tighten capscrews to standard torque.Refer to "Installation" procedure to install assem-bly on final drive.

REAR WET DISC BRAKE BLEEDING PROCEDURE

If hydraulic lines were removed from brake hous-ing, be certain suction plug on hydraulic tank hasbeen tightened. If plug is left loose and engine isstarted, hydraulic oil will leak from the plug.

1. Block wheels of truck.

2. A male quick-disconnect fitting is installed on theback of each wet disc brake housing adjacent tothe rear brake shuttle valve. Locate both fittingsand clean thoroughly.

3. Assemble an open-close valve with a drain hoseand a female quick-disconnect fitting on one end.

4. Attach hose/valve and quick-disconnect assemblyonto brake housing quick-disconnect fitting.

5. Start engine and allow accumulators to charge.Operate engine at 1000 rpm and apply brake lockvalve. Slowly open valve attached to rear brakeand drain oil into a clean container (5 gal. mini-mum) for one minute or until a clear, steady flowof oil is obtained.

6. Shut off engine and remove hose/valve and quick-disconnect assembly from brake assembly.

7. Repeat Steps 4 and 5 with other rear brake.

8. After bleeding procedure is completed, fill hydrau-lic tank if needed.

FIGURE 6-11. PISTON REMOVAL/INSTALLATION

1. Eyebolt 4. Retaining Bracket & Capscrews 7. Disc Pack2. Piston Assembly 5. O-Ring Seal Bore 8. O-Ring3. Brake Housing 6. Rotating Hub 9. Capscrews


REAR BRAKE DISC WEAR INDICATORRear brake disc wear should be checked every 1000hrs. using the wear indicator tool (Figure 6-12)mounted in one of the rear brake housings. On a newtruck, the wear indicator tool is located in the lower leftbrake housing near the cooling oil line.

1. Park truck on a level surface and apply park brake.Shut engine down and block rear wheels.

2. Thoroughly clean both rear brake assemblies,especially the area surrounding the lower coolingoil lines.

3. Place the transmission in neutral and start engine.Apply brake lock and keep parking brake applied.

4. Remove wear indicator cover (1, Figure 6-12).

5. Operate engine at 1000 RPM.

6. Push rod (2) in until it stops against brake piston.

7. Measure the distance from rod shoulder (2) tohousing face (3).

•• If rod shoulder (2) is even with the housing face(3) or below, disc pack is worn to maximum safewear limits. Brakes should be scheduled for re-build.

•• If rod shoulder (2) does not go to housing face(3), brake disc wear is still within allowable limits.

8. Pull rod (8) out until it stops against tool housing(6) and install protective cover (1).

9. Release brake lock. Shut engine down.

NOTE: Checking disc wear in both brake assembliesis recommended. Disc wear in one brake assemblymay be different from the other due to dissimilar op-eration of parts and/or haul profiles which requirerepeated braking/retarding while steering in one di-rection only.

Removal/Installation From One Brake To Another

The brake disc wear indicator tool is inserted in a portwhich is open to cooling oil. Removal of the brake discwear indicator will cause the loss of some of this oil.Advance planning will help to minimize oil loss.

1. Consider scheduling brake disc wear inspectionsalong with the recommended 1000 hr. change ofhydraulic oil and filters. Also consider obtainingan additional brake disc wear indicator tool forpermanent installation on truck. If both brake as-semblies are equipped with disc wear indicators,future checks will not require removal.

2. Perform steps 1 and 2, "REAR BRAKE DISC WEARINDICATOR".

3. To prevent hydraulic oil from siphoning from tank,loosen the plug above the return tube in the topcover of the hydraulic tank. Refer to HydraulicTank, Section "L".

4. Obtain a VM0315 (0.750 - 16 UNF-2B) O-ring plugand be prepared to insert in hole as indicator toolis removed. Position container to catch oil.

5. Remove the brake disc wear indicator tool, installO-ring plug in place of tool. Inspect brake discwear indicator and replace O-rings (4, 5 & 7,Figure 6-12).

6. Move to other brake assembly. Locate O-ring plugin the lower part of brake housing near the coolingoil line. Be prepared to insert indicator tool in holeas O-ring plug is removed. Position container tocatch oil.

7. Remove the O-ring plug, install brake disc wearindicator tool in place of plug.

8. Refill hydraulic tank as required. Tighten the plugabove the return tube in the top cover of thehydraulic tank. Refer to Hydraulic Tank, Section"L".

9. Perform steps 3 through 9, "REAR BRAKE DISCWEAR INDICATOR".

10. If brake rebuild is necessary, refer to Removal,Disassembly, Assembly, Installation this section.

NOTE: If any leakage is observed around the brakedisc wear indicator tool, replace O-rings (4, 5 and 7Figure 6-12).

FIGURE 6-12. WEAR INDICATOR TOOL

1. Protective Cover 5. O-ring2. Indicator Rod Shoulder 6. Tool Housing3. Housing Face (Ref.) 7. O-ring4. O-ring 8. Indicator Rod


PARKING BRAKE The Parking Brake Assembly is mounted to the rear ofthe Allison transmission. It is controlled by an actuatorwhich is spring applied and hydraulically released.

Removal/Installation

If park brake assembly requires repair, refer to AllisonTransmission Service Manual for procedure.

Park Brake Lining Adjustment

1. With park brake released, move truck as requiredto position access hole in park brake drum foraccess to the adjusting star wheel (1, Figure 7-1).

2. Shut down engine. Securely block all wheels.

3. Remove hose at actuator.

4. Install a hand operated hydraulic pump with a0-5000 psi (0-35 000 kPa) gauge to the fitting onthe park brake actuator (2, Figure 7-2).

5. Apply 1750 psi (12 066 kPa) to the park brakeactuator to release the brake.

6. Turn star wheel until linings are tight against brakedrum.

7. Back off star wheel three turns.

8. Relieve hand operated hydraulic pump pressureand remove pump. Install hydraulic line on fitting(2, Figure 7-2).

Park Brake Linkage Adjustment

NOTE: If transmission is exchanged or brake leverand/or cam is changed, it will be necessary to make apreliminary adjustment for lever to actuator linkage.

1. Refer to Steps 1 through 5 of park brake liningadjustment to position actuator in released posi-tion.

2. Turn star wheel adjuster until linings are tightagainst brake drum.

3. Install link (3, Figure 7-2) to actuator (1).

4. Observe the relationship of park brake actuatorlink (3) to the eye of park brake lever (4).

5. If the relationship is not close enough to allow thelever to slide on the link pin, the park brake leverwill have to be removed from the serrated shaftand moved to a position that will allow the lever toslide on the link pin.

6. Install link pin, washer and key.

7. Proceed with the lining adjustment.

FIGURE 7-1. PARKING BRAKE ADJUSTMENT

1. Star Wheel Adjuster

FIGURE 7-2. PARK BRAKE LINKAGE ADJUSTMENT

1. Actuator 3. Link2. Hydraulic Hose Fitting 4. Park Brake Lever

J07007 4/92 Parking Brake J7-1

PARK BRAKE ACTUATOR ASSEMBLY

The decal shown above is on the top of the parkbrake actuator assembly. Do not remove nuts fromspring retainer plate end of assembly until springforce is removed. Failure to follow instructionscould result in serious personal injury.

Removal

1. Block wheels of truck securely before disconnect-ing park brake.

2. With key switch "On" and engine running, moveparking brake switch to "Off" position.

3. Remove cotter pin (1, Figure 7-3) and pin (2).

4. Move parking brake switch to "On" position, turnkey switch "Off" and shut engine down.


Before removing any hydraulic lines or compo-nents, be sure steering accumulator is bled down.Turn key switch "Off", shut down engine and waitat least 90 seconds. Rotate steering wheel backand forth; no front wheel movement should occur.

5. After steering accumulator is completely bleddown, remove hydraulic line at actuator. Cap/plughydraulic line to prevent dirt entry.

6. Remove park brake actuator from rear cover oftransmission.

Installation

1. Mount park brake actuator on rear cover of trans-mission. Tighten capscrews to standard torque.

2. Connect hose to fitting of park brake actuator.

NOTE: It is not necessary to bleed park brake actuator.

3. Start engine and allow hydraulic system to com-pletely charge.

4. With key switch "On" move park brake switch to"Off" position.

5. Connect park brake actuator to lever of park brake.With park brake in "Off" position, linings should notbe in contact with drum. If adjustment is neededrefer to "Park Brake Adjustment" Procedure.

6. Move parking brake switch to "On" position, turnkey switch "Off" and shut engine down. Removeblocks from wheels.

FIGURE 7-3. PARK BRAKE ACTUATOR ATTACHMENT

1. Cotter Pin 2. Pin w/Washers

J7-2 Parking Brake J07007 4/92

Disassembly

1. Remove nuts (2, Figure 7-4) on actuator end ofassembly from the three retainer rods (7).

Do not allow retainer rods to turn with nuts.

2. Remove actuator assembly (3) from spring podassembly (6).

NOTE: Normal service of the parking brake actuatorassembly will NOT require disassembly of the actuatorspring pod assembly. If service is required, refer to"Actuator Spring Pod Disassembly/Assembly".

3. Remove plunger (1), wiper (4) and seal (5) fromthe actuator assembly housing.

Assembly

1. Clean and inspect all parts thoroughly.

2. Install new seal (5, Figure 7-4) and wiper (4). Installtip of seal toward eye end of actuator, tip of wiperpoints away from eye end.

3. Place plunger (1) in housing of actuator (3). Installactuator assembly onto three retainer rods ofspring pod assembly (6).

4. Install nuts (2). Tighten nuts to standard torque.

Actuator Spring Pod Disassembly

1. Remove clamp (6, Figure 7-5) and boot (8).

2. Weld a nut to one end of 0.375 in. (9 mm) threadedrod 12 in. (304 mm) long, this will be the springcompression rod (1).

3. Install compression rod with welded nut (1) inrecess of actuator base.

FIGURE 7-5. ACTUATOR SPRING POD

1. Compression Rod 6. Clamp2. Retainer Plate 7. Retainer Rods3. Washer 8. Boot4. Nut 9. Spring5. Self Locking Nut 10. Spring Pod Base

FIGURE 7-4. PARK BRAKE ACTUATOR ASSEMBLY

1. Plunger 4. Wiper2. Nuts 5. Seal3. Actuator Assembly 6. Spring Pod Assembly

7. Retainer Rods

J07007 4/92 Parking Brake J7-3

4. Install washer (3), nut (4) to spring retainer end ofcompression rod.

5. Tighten nut (4) enough to relieve force on retainerrod nuts (5).

Position spring assembly so the retainer plate isnot pointed at anyone.

6. Remove retainer rod nuts (5).

7. Hold nut (4) of compression rod (1) and unscrewrod by the welded nut on compression rod.

8. Free length of spring is approximately 14.8 in. (375mm).

9. After all spring pressure is released, remove springcompression rod.

10. Separate retainer plate (2), spring (9) and actuatorbase (10).

Actuator Spring Pod Assembly

1. Install spring compression rod (1, Figure 7-5) withwelded nut in recess of actuator base (10).

2. Install spring (9) and retainer rods (7) to actuatorbase.

3. Place spring retainer plate (2) on end of spring withcompression rod through center hole. Installwasher (3) and nut (4) to compression rod.

4. Hold nut (4) on retainer plate end of spring.

5. Align retainer rods with holes of retainer plate.Tighten welded nut to compress spring.

6. Compress spring until retainer rod nuts (5) can beinstalled.

7. The assembled length of spring pod (Dimension"A", Figure 7-6) should be 8.312 in. (211 mm).

8. Remove spring compression rod.

9. Install boot (8, Figure 7-5) and clamp (6).

PARK BRAKE BURNISHINGNOTE: New brake drum and brake shoe linings needto be burnished before truck is placed in production.

1. When burnishing brake, operate truck in a levelarea free of obstacles and other equipment.

2. Place range selector in "Drive" position and accel-erate truck to a maximum speed of 10 MPH (16km/ph). With truck in motion, release throttle andmove range selector to "Neutral" position andmove park brake switch to "On" position.

3. Repeat Step 2 five times at one minute intervals.

4. After burnishing, check that lining to drum clear-ance is correct. Adjust as required. Refer to "ParkBrake Lining Adjustment".

FIGURE 7-6. ASSEMBLED SPRING LENGTH

J7-4 Parking Brake J07007 4/92

SECTION L

HYDRAULIC SYSTEM

INDEX

HYDRAULIC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L2-1HYDRAULIC SYSTEM DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . L2-1

HYDRAULIC SYSTEM COMPONENT REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . L3-1TANDEM HYDRAULIC PUMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-1

Pump Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-2Pump Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-4Cartridge Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-5

Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-5Cartridge Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-7

HYDRAULIC TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-9Filling Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-9

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-9Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-10

HYDRAULIC TANK BREATHERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-10HYDRAULIC FILTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-10

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-11Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-11

DIFFERENTIAL PRESSURE SWITCH TESTING . . . . . . . . . . . . . . . . . . . . . L3-12Test Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L3-13

STEERING CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-1STEERING CIRCUIT OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L4-1STEERING CIRCUIT COMPONENT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . L4-1

STEERING CONTROL VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-1Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-2Cleaning and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-5Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-5Alternate Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L5-5

STEERING CIRCUIT COMPONENT REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-1ACCUMULATORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-2Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-2Cleaning and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-2Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-3

LOW PRESSURE ACCUMULATOR PRESSURE SWITCH . . . . . . . . . . . . . . . . . . L6-3ACCUMULATOR CHARGING PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . L6-4INLINE FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-5

Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-5STEERING CYLINDERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-6

Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-6

L01009 5/92 Index L1-1

Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-6BRAKE/STEERING PUMP REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-7

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-7Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-7Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-7Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-13

PUMP SPECIFICATIONS CHART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L6-21

HOIST CIRCUIT OPERATION AND COMPONENT DESCRIPTION . . . . . . . . . . . . . . L7-1CIRCUIT OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L7-1

Hoist Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L7-1Auxiliary Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L7-2Counter Balance (overcenter) Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . L7-2Hoist Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L7-2Check Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L7-2

HOIST CIRCUIT COMPONENT REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-1HOIST VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-1

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-1Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-2Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-3

HOIST CYLINDER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-4Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-4Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-4Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-6Cleaning and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-6Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L8-6Hoist Cylinder Mounting Bearing Replacement . . . . . . . . . . . . . . . . . . . L8-6

HYDRAULIC CHECK-OUT PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-1GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-1STEERING CIRCUIT CHECK-OUT & ADJUSTMENT PROCEDURE . . . . . . . . . . . . L10-1INITIAL SYSTEM SET-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-1

Accumulator And Piston Pump Checks . . . . . . . . . . . . . . . . . . . . . . . . L10-1Steering Valve Leakage Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-3Steering Cylinder Leakage Check . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-3

TROUBLESHOOTING CHART (STEERING SYSTEM) . . . . . . . . . . . . . . . . . . . L10-4HOIST CIRCUIT CHECKOUT & ADJUSTMENT PROCEDURE . . . . . . . . . . . . . . . L10-6

AUXILIARY VALVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-6Pressure Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-6Leakage Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-6

Checking And Adjusting Hoist System Pressure Relief Valve . . . . . . . . . . . . L10-7Checking And Adjusting "Power Down" Pressure . . . . . . . . . . . . . . . . . . . L10-7

TROUBLESHOOTING CHART (HOIST SYSTEM) . . . . . . . . . . . . . . . . . . . . . . . . L10-8

STEERING SYSTEM DATA SHEET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-11

HOIST SYSTEM DATA SHEET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L10-12

HYDRAULIC SYSTEM FLUSHING PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . L10-13

L1-2 Index L01009 5/92

HYDRAULIC SYSTEM

HYDRAULIC SYSTEM DESCRIPTIONThe hydraulic system consists of the hoist, steering,brake apply and brake cooling circuits. The followinginformation discusses basic operation and oil flowthrough the entire system when the engine is runningand all controls are in the neutral position. Additionaland more detailed information regarding the brakesystem can be found in Section ‘‘J’’. Additional infor-mation regarding the operation of individual hoist andsteering circuit components can be found in this Sec-tion. Refer to Figure 2-3 for the location of individualcomponents on the truck and to the hydraulic systemschematic in Section ‘‘R’’.

The hydraulic tank (Figure 2-1), located on the left sideof the frame provides the oil supply for the entiresystem. The tandem pump oil supply tube (1, Figure2-1) is positioned above the oil level in the tank andreceives oil by siphoning oil from inside tube (2). Thisarrangement allows pickup of clean oil while contami-nants not trapped by the system filters and screensreturn to the tank and settle to the bottom.

The shaft end of the tandem pump (2, Figure 2-2),mounted on the rear of the transmission PTO drive (3)provides oil to the open center hoist valve. Oil leavingthe hoist valve is routed to the rear, dual filter locatedbehind the left front wheel. The outlet of the cover endcartridge of the tandem pump is routed to the frontfilter. The two supplies are combined after the oil isfiltered and routed to the heat exchanger located underthe radiator. A ‘‘Tee’’ ahead of the heat exchangerroutes oil back to the hydraulic tank through a reliefvalve (3, Figure 2-1) if pressure exceeds 85 psi (586kPa).

After the oil is cooled in the heat exchanger the oil isrouted to the rear brake system and used to cool thedisc brakes during truck operation and then is returnedto the hydraulic tank. A portion of the oil leaving theheat exchanger is routed through a filter screen to theinlet of the steering/brake supply pump mounted onthe front of the transmission PTO drive.

The brake/steering pump (4, Figure 2-2) is a piston typepump. It contains an internal pressure compensator toprovide "standby" oil pressurized to 2750 psi (18.9MPa) at all times to the steering and brake circuits.There is no oil flow from the pump unless there is ademand for oil from one of the circuits.

FIGURE 2-1. HYDRAULIC TANK ASSEMBLY

1. Tandem Pump Oil Supply Tube

2. Tube

3. Relief Valve4. By-Pass Return 5. Cooling Circuit Return

FIGURE 2-2. HYDRAULIC PUMPS

1. Fuel Tank2. Tandem Pump

3. PTO4. Brake/Steering Pump

L02007 8/90 Hydraulic System L2-1

FIGURE 2-3. HYDRAULIC SYSTEM COMPONENT LOCATION

L2-2 Hydraulic System L02007 8/90

Pressure oil from the brake/steering pump is routed tothe auxiliary valve, steering system components andbrake system components.

A pressure reducing valve in the Auxiliary manifoldreduces the 2750 psi (18.9 MPa) pressure to provide125 psi (862 kPa) oil pressure to the hoist pilot controlvalve to control the hoist valve mounted on the fueltank. When the hoist valve is actuated, oil flows fromthe hoist valve to extend the hoist cylinders. An Over-center valve provides a hydraulic ‘‘cushion’’ to preventdamage to the cylinders when reaching the end of thefully extended stage. A pressure switch mounted onthe Auxiliary Manifold activates a Low Steering Pres-sure warning light and horn if steering circuit pressuredecreases to 1800 psi (12.4 MPa).

This oil supply is used for releasing the parking brakeactuator, operation of the hoist valve and steeringcircuit pressure detection.

The remainder of the volume of oil from the brake/steer-ing pump is routed to a manifold and through checkvalves to the three accumulators as shown in Figure2-3. The check valves maintain oil pressure in theaccumulators in the event of a loss of oil supply fromthe brake/steering pump. This supply of pressurized oilis available to steer the truck and bring it to a safe stop.

The smaller, outboard accumulator and the centeraccumulator provide oil to the Low Brake PressureDetection Module located under the accumulators.This module senses brake pressure to provide a warn-ing if the brake system pressure falls below 2000 psi(13.8 MPa) and automatically applies the brakes ifpressure falls below 1650 psi (11.4 MPa). This modulealso contains valves used to manualy bleed the hydrau-lic pressure from the brake system accumulators forsystem maintenance and repair.

Oil is routed from the Low Brake Pressure DetectionModule to the Brake Manifold to provide an oil supplyfor the retarder, front and rear brake treadle valves andthe brake lock circuit.

The inboard accumulator supplies oil to the steeringcircuit. A portion of the oil is routed from the accumu-lator to the Brake Manifold containing the accumulatorbleeddown solenoid. When the engine is shut downand the key switch turned ‘‘Off’’, oil pressure stored inthe steering accumulator is drained back to the tank.Oil flow is also routed through a filter screen to theclosed center Steering Control Valve. If the operatorturns the steering wheel, the oil supply is directed tothe steering cylinders to extend one cylinder and toretract the opposite cylinder.

FIGURE 2-4. ACCUMULATOR INSTALLATION

1. Steering Accumulator 2. Rear Brake Accumulator 3. Front Brake Accumulator 4. Brake Accumulator Bleedown Valves 5. Low Brake Pressure Detection Module 6. Pressure Test Port 7. Brake System Warning Pressure Switch 8. Oil Supply to Accumulators 9. Manifold10. Accumulator Check Valves

L02007 8/90 Hydraulic System L2-3

• Block Wheels of Truck!

• Turn key switch ‘‘Off’’ and shut down engine. Wait at least 90 seconds to bleed down thesteering accumulator. Rotate the steering wheel back and forth; no movement shouldoccur.

• Bleed down the brake accumulators by turning the Bleeder Valve handles counterclock-wise to open and wait at least 90 seconds. When accumulators are completely bleddown, close bleeder valves by turning Bleeder Valve handles clockwise. Do not leaveopen.

The following procedure should be observed prior to anyrepairs and maintenance to hydraulic system components:

This hydraulic system contains stored energy. Always relieve pressurebefore disconnecting any hydraulic line. Tighten all connections securelybefore starting the engine.

Hydraulic fluid escaping under pressure can have sufficient force to entera person’s body by penetrating the skin and cause serious injury andpossibly death if proper medical treatment by a physician familiar withthis type of injury is not received immediately.

Always maintain complete cleanliness when opening any hydraulic con-nection. Insure that all system lines and components are capped to preventcontamination.

L2-4 Hydraulic System L02007 8/90

HYDRAULIC SYSTEM COMPONENT REPAIRTANDEM HYDRAULIC PUMP

Removal

1. Block the wheels of the truck.Turn the key switch‘‘Off’’ and allow at least 90 seconds for the steeringaccumulator to bleed down. Open the valves lo-cated in the Low Brake Pressure Detection Mod-ule to manually bleed the pressure from the brakeaccumulators.

Relieve pressure before disconnecting hydrauliclines. Tighten all connections securely before ap-plying pressure.

Hydraulic fluid escaping under pressure can havesufficient force to enter a person’s body by pene-trating the skin and cause serious injury and pos-sibly death if proper medical treatment by aphysician familiar with this type of injury is notreceived immediately.

2. Loosen the center plug (4, Figure 3-2) on the topcover (2) of the hydraulic tank.

3. Place a container under the pump (2, Figure 3-1).Be prepared to catch approximately 10 gal (38 l)of oil.

4. Remove the pump inlet and outlet hose flangesand remove hoses. Cap hoses to prevent con-tamination.

5. Remove capscrews and remove the pump fromthe PTO.

6. Remove the oil filter elements and inspect forcontamination. If excessive amounts of contami-nation are found, the hydraulic tank should becompletely drained and thoroughly cleaned.

7. Move pump to a clean work area for disassembly.

Installation

1. Install a new O-ring on pump mounting flange.Align splines on pump with splines in PTO. Securepump to PTO housing with capscrews and lock-washers. Tighten to standard torque.

FIGURE 3-1. HYDRAULIC PUMP INSTALLATION

1. Fuel Tank2. Tandem Hydraulic Pump

3. Transmission PTO4. Steering/Brake Pump

FIGURE 3-2. HYDRAULIC TANK

1. Cover Gasket2. Cover3. Capscrews

4. Vent Plug5. Filler Tube

L03006 7/93 Hydraulic System Component Repair L3-1

2. Uncap outlet lines and attach to the proper con-nections using new O-rings.

3. Install new O-ring and install inlet hose on pumpand secure with capscrews.

4. Remove the cover (2, Figure 3-2) from the hydrau-lic tank and fill the suction tube for the tandempump with clean Type C-3 hydraulic oil. Loosenthe capscrews on the pump inlet to removetrapped air in line. After air is bled from line, tightencapscrews to standard torque.

5. Refill tank to top of the filler tube (5). Tighten theplug (4) in the tank cover.

6. Install new oil filter elements.

Pump Disassembly

1. Support the pump on blocks or clamp the body ina vise as shown in Figure 3- 3. If a vise is used, useprotective jaws to avoid damage to outlet bodyand its machined surfaces.

2. Mark the pump inlet, outlet and cover for correctreassembly (Figure 3-3).

3. Remove the cover screws (1, Figure 3-6) and liftend cover (2) from the pump. This will expose thecover end cartridge. Discard square cut seal (5)and O-ring (6).

4. Pull cover end cartridge from the inlet housing(Figure 3-4).

5. Set cover end cartridge aside for disassembly.

6. Separate inlet housing and outlet body as shownin Figure 3-5. This will expose shaft end cartridge.Discard square cut seal and O-ring (5 & 6, Figure3-6).

7. Rotate shaft to loosen shaft end cartridge thenremove the cartridge from outlet body (25). Setaside for disassembly during Step 11.

8. Remove spirolox ring (19). Slide shaft (22) andbearing (21) from outlet body (25).

FIGURE 3-3. REMOVAL OF COVER SCREWS

FIGURE 3-4. REMOVAL OF COVER END

FIGURE 3-5. INLET HOUSING REMOVAL

L3-2 Hydraulic System Component Repair L03006 7/93

9. If bearing (21) is worn, remove retaining ring (20)and press bearing from the shaft with an arborpress.

10. Remove spacer (23) and shaft seal (24) from theoutlet body (25). Be careful not to damage the boreareas where the seals are located.

NOTE: Preassembled and tested pump cartridges areavailable as service items, if needed.

FIGURE 3-6. HYDRAULIC PUMP

1. Screw2. End Cover3. Backup Ring4. O-Ring5. Square Cut Seal6. O-Ring7. Outlet Support Plate

8. Seal Pack Sub-Assemblies 9. Flex Side Plate10. Rotor11. Vanes & Inserts12. Ring13. Flex Side Plate14. Seal Pack Sub-Assemblies

15. Inlet Support Plate16. Locating Pins17. Screw18. Inlet Housing19. Spirolox Retaining Ring20. Retaining Ring

21. Bearing22. Shaft23. Washer (Spacer)24. Primary Shaft Seal25. Outlet Body26. Seal


Pump Assembly

1. Clamp outlet body (25, Figure 3-6) in a vise orplace on 2 x 4 wood blocks to facilitate assembly.

2. Lubricate primary shaft seal (24) with petroleumjelly and place in position within outlet body (25),garter spring up. See Figure 3-7 for seal arrange-ment.

3. Use seal installation tool shown in Figure 3-8 toprevent damage to the seal. Press seal (24, Figure3-6) into the body until it bottoms out against theshoulder.

4. Press shaft (9) into the new bearing with an arborpress while supporting the bearing inner race.Refer to Figure 3-7 for correct location of bearingon the shaft. Install a small retaining ring (20,Figure 3-6) behind the bearing on the shaft.

5. Place the bearing spacer washer (23) over theshaft, against the front of the bearing. Use plastictape over the shaft end to prevent damage to theseal. Lubricate with petroleum jelly and carefullypush the shaft through the seal until the bearingand spacer are in location within the body.

6. Install the large spirolox ring (19) into the outletbody retaining ring groove located just behind thebearing.

7. Install square cut seal (5) into outlet body (25).

8. Install O-ring (4) and backup ring (3) on the car-tridge outlet support plate hub.

9. Carefully install shaft end cartridge over shaft (22)and into outlet body (25) with one of the chamferson the ring in alignment with the outlet port.

10. Lubricate and install O-ring (6) between the largeinlet housing (18) and outlet body (25). LocateO-ring in O-ring groove of the outlet body.

11. Install inlet housing (18) in position; move back andforth until the cartridge pins drop into the align-ment holes located within the housing.

12. Turn the inlet housing slightly until the alignmentmarks are in line and the large screw holes arealigned.

13. Turn pump shaft by hand to check for free rotationof the cartridges.

14. Install a square seal (5) into the outlet cover (2).

15. Install O-ring (4) and backup ring (3) on the coverend cartridge outlet support plate hub.

16. Carefully install cover end cartridge over shaft (22)and into the inlet housing.

17. Turn cartridge slightly to bring into alignment thepin holes and cartridge alignment pins.

18. Install outlet cover to inlet housing O-ring seal (6)over the cartridge and up against the inlet housing.

19. Make sure square cut seal is in place within thecover. Align the cover to agree with the alignmentmarks and gently slide the cover over the outletcartridge.

FIGURE 3-7. SHAFT SEAL ARRANGEMENT

1. Primary Seal2. Standard Shaft

3. Steel Ball

FIGURE 3-8. PRIMARY SHAFT SEAL DRIVER


Be careful not to cut square cut seal (5) or pinchO-ring (6) during cover installation.

20. Oil and install capscrews (1). Tighten capscrews to255-275ft.lbs. (346-373 N.m) torque.

21. Turn the pump shaft to check for free rotation ofthe cartridges.

Cartridge Disassembly

Disassemble the two cartridge kits, one at a time,according to the following instructions. Keep partsseparated from each other during inspection, repair,and assembly.

1. Remove O-ring (4, Figure 3-6), backup ring (3) andsquare cut seal (5) from the outlet support plate.

2. Scribe a line across the outer surface of the car-tridge kit. (Refer to Figure 3-9). The scribe markingwill provide a reference for parts alignment duringassembly.

3. Place the cartridge on a flat surface (outlet supportplate down) and remove the two socketheadscrews (17, Figure 3-6).

Do not slide flex plates across the ring and rotor.Burrs on the ring or rotor can cause deepscratches in the soft bronze surface.

4. Slide inlet support plate (15) and seal pack sub-assemblies (14) off the cartridge. DO NOT allowthe flex side plate (13) to slide with the supportplate.

5. Move flex side plate (13) off center just enough tolift up and away without sliding. Refer to Figure3-10.

6. Place a small clean piece of wood over the ex-posed ring and rotor. Turn cartridge and woodupside down as shown in Figure 3-11.

7. Slide outlet support plate (7, Figure 3-6) and sealpack sub-assemblies (8) off flex side plate (9). DONOT permit flex side plate (9) to move across thering and rotor.

8. Move flex side plate (9, Figure 3-6) off center justenough to lift up and away without sliding. Referto Figure 3-10.

9. Lift ring (12, Figure 3-6) away from rotor (10) andvanes (11). Locate the arrow stamped into therotor periphery.

10. Remove the vanes and inserts in order, starting atthe arrow. Keep them in order for inspection.

NOTE: Do not remove cartridge locating pins (16,Figure 3-6) from the inlet support plate unless they aredamaged. The pins are of a drive-loc type and can bedifficult to remove.

Inspection

1. All parts must be thoroughly cleaned and keptclean during inspection and assembly. The closetolerance of the parts makes this requirement veryimportant.

2. Clean all removed parts, using a cleaning solventthat is compatible with the system oil.FIGURE 3-9. SCRIBING THE CARTRIDGE


When using cleaning solvents follow solvent manu-facturers instructions.

NOTE: Compressed air may be used in cleaning, butit must be filtered to remove water and contamination.

3. Discard the square cut seals, O-rings, backup ringand seal sub-assemblies. Use new seal kits forassembly.

4. Check the cartridge wear surfaces for pickup,scoring and excessive wear. Slight heat discolora-tion of the flex side plate bronze surface is normal.Score marks deeper than 0.001 in. (0.025 mm)and scratches deeper than 0.002 in. (0.050 mm)indicate a new part is needed. Slight scoringand/or scratches can be removed with an oiledhoning stone.

DO NOT use a dry stone on bronze surface orscratches will result.

5. Inspect both sides of each vane (11, Figure 3-6)and insert in order. If pickup, heavy wear or scor-ing is found, inspect the appropriate rotor (10)slot. Replace scored parts.

NOTE: Inspect each vane tip for excessive wear. Ex-cessive vane tip wear will reduce pump efficiency.

6. Inspect ring (12) for vane chatter marks, wearand/or scratches. Replace if scoring is evident.

FIGURE 3-10. INLET FLEX SIDE PLATE REMOVAL


Replacement ring width must be identified to thering being replaced or reduced life of output flowwill result. The minimum ring to rotor clearancelimit is 0.0016 in. (0.0406 mm).

NOTE: All cartridge kit parts must be free of burrs.Stone the mating surfaces of each part with an oiledhoning stone prior to assembly. Clean parts after ston-ing.

7. Vane to rotor wear can be checked by insertingthe vane in the rotor slot and checking for exces-sive play. Replace rotor (10, Figure 3-6) and vanes(11) if wear is evident.

8. Rotate bearing (21) while applying pressure tocheck for wear, looseness and pitted or crackedraces.

9. Inspect the seal and bushing mating surfaces onshaft (22) for scoring or wear. Replace the shaft ifwear exceeds 0.005 in. (0.127 mm) diametricalchange, or if marks cannot be removed by lightpolishing. If wear is found in the bushing area, anew bushing will be required.

Cartridge Assembly

NOTE: Coat all parts except seals and backup ringswith clean Type C-3 hydraulic oil to facilitate assemblyand provide initial lubrication. Use small amounts ofpetroleum jelly to hold the O-rings in place duringassembly.

1. The direction of rotation is viewed from the shaftend. Right hand rotation is clockwise; left handrotation is counterclockwise. Be certain pumpassembly provides same rotation as found duringdisassembly.

NOTE: Assemble shaft end cartridge in the directionof rotation noted at disassembly. Assemble cover endcartridge in reverse of the shaft end cartridge.

NOTE: If locating pins (16, Figure 3-6) were removedfrom inlet support plate (15), install new pins withlocking flutes located within the inlet support plate.Drive the new pins into the support plate with a softtipped hammer.

2. Place the inlet and outlet support plates on a flatsurface. Install seal pack sub-assemblies (8 & 14)into cavities with seal retainer surface up (O- ringsfacing downward into the cavities).

FIGURE 3-11. CARTRIDE DISASSEMBLY


3. Place flex side plates (9 & 13) over each of thesupport plates with bronze wear surface facingup. Align scribe marks to make sure the correctflex side plate is used with the correct supportplate (bronze wear surfaces must face rotor whenassembled).

NOTE: Flex side plates develop a wear pattern with therotor and vanes and should not be interchanged.

4. For right hand rotation units, set the rotor on a flatwooden board with the arrow pointing right (forleft hand rotation, the arrow should point left).

5. Assemble the vanes and inserts into the rotor inreverse order of disassembly. Make sure thesharp chamfer edge of each vane leads in thedirection of rotation. All vanes must move freely inthe rotor slots with no evidence of bind.

6. Assemble the ring (12, Figure 3-6) over rotor (10)and vanes (11) with arrow pointing in the samedirection as the rotor. Lubricate the top surface ofthe rotor and vanes liberally with Type C-3 hydrau-lic oil.

7. Locate the scribe mark on ring (12), outlet supportplate (7) and flex side plate (9). Hold the outletsupport plate and flex plate together and assem-ble over the ring and rotor with the scribe marksin line.

8. Hold the cartridge together to prevent movementand turn the assembly over so the outlet supportplate rests on a flat surface.

9. Lubricate the exposed surface of the rotor andvanes with system oil. Locate the scribe mark oninlet support plate (15) and flex side plate (13).

10. Hold the inlet support plate and flex side platetogether and assemble over the exposed ring,rotor and vanes. Make sure the scribe marks arein line.

NOTE: The O.D. of all component parts of the cartridgekit must be in line with each other or the cartridge willbind during assembly. Align the cartridge as follows:

a. Build a ‘‘V’’ block from hardwood (ReferenceFigure 3-12) or use a metal ‘‘V’’ block if it isavailable.

b. Place the cartridge into the ‘‘V’’ block on its side.

c. Loosen socket head screws (17, Figure 3-6)enough to allow each section of the cartridgeto come into alignment within the ‘‘V’’ block.

d. Tighten the socket head screws (17) to 100in.lbs. (11.29 N.m) torque.

e. Check alignment again after tightening.

11. Check rotor (10) for bind by inserting the indexfinger through the shaft opening of inlet supportplate (15). Hold the cartridge kit in a horizontalshaft position and lift the rotor with the finger. Therotor should move freely back and forth within thecartridge. If the rotor binds, open the kit, clean andstone all possible areas of bind, then reassembleusing the aforementioned procedure. The rotorMUST move freely within the cartridge when as-sembled.

12. Repeat Steps 1 thru 11 for assembly of othercartridge kit.

FIGURE 3-12.CARTRIDGEALIGNMENT

BLOCK


HYDRAULIC TANK

Filling Instructions

NOTE: If filling is required, use clean Type C-3 hydrau-lic oil only.

Prior to opening the hydraulic tank, allow at least90 seconds for the accumulators to bleed downafter engine shutdown with the key switch ‘‘Off’’.

1. With the body down, shut down engine and turnkey switch ‘‘Off’’. Wait at least 90 seconds.

2. Remove cap from fill tube (7, Figure 3-13) and addclean, filtered Type C-3 hydraulic oil until oil is atthe top of fill tube.

NOTE: The final filter in the filling apparatus must be 3micron.

3. Replace fill cap.

4. Start the engine, raise and lower the dump bodythree times.

5. Continue to repeat Steps 1 through 4 until oil levelis maintained at the fill tube.

NOTE: When engine is shut down, oil should be visiblein sight glass.

If a component in the hydraulic system should fail, andforeign particles are evident, the system must beflushed. Refer to ‘‘Hydraulic System Flushing’’ instruc-tions.

Removal

1. Block the wheels of the truck. Turn keyswitch ‘‘Off’’and allow at least 90 seconds for the steeringaccumulator to bleed down. Open the manualbleedown valves on the Low Brake Pressure De-tection Module to relieve the oil pressure in thebrake system accumulators. Close valves whenbrake accumulators are bled down.

2. Loosen the vent plugs (1, Figure 3-13). Drain thehydraulic tank by use of the drain (9) located inthe bottom of the tank. Be prepared to catchapproximately 95 gal (360 l) of oil.

3. Thoroughly clean the outside of the hydraulic tank.

4. Disconnect hydraulic lines. Plug lines to preventspillage and possible contamination to the sys-tem. Tag each line as removed for proper identifi-cation during installation. Disconnect wires oninboard side of tank. Remove the transmisssionfiller pipe (6) and position to allow tank removal.

Take care to avoid contact with hot oil if truck hasbeen operating. Avoid spillage and contamination.

5. Attach a lifting device to the hydraulic tank.

6. Remove the nuts, washers,capscrews, lockwash-ers and U-bolts securing the hydraulic tank to theframe.

7. Move hydraulic tank to a clean work area fordisassembly or repair.

FIGURE 3-13. HYDRAULIC TANK

1. Vent Plugs2. Breather Elements3. Capscrew4. Cover5. Gasket

6. Transmission Fill Pipe 7. Tank Filler Tube 8. Sight Gauge 9. Drain Plug10. Lower Mount


Installation

1. Install hydraulic tank and secure with u-bolts,washers and nuts at upper mounts. Install cap-screw, washers, rubber mount and nut in lowermount. Tighten to standard torque.

2. Remove caps from hydraulic lines and attach tothe proper connections using new O-rings andgasket where applicable.

3. Attach transmission filler pipe assembly to thetank. Reconnect wiring to temperature sendingunit and thermostat switch on inboard side oftank.

3. With the cover (4, Figure 3-13) removed, fill thehydraulic tank with C-3 hydraulic oil. Be certain tofill the center, internal tube supplying oil to thetandem pump. Bleed all air from hydraulic lines.

4. Install the tank cover using a new gasket. Tightenthe vent plugs (1) to assure a positive seal.

5. Refer to ‘‘Filling Instructions’’ and fill tank to obtainproper oil level.

HYDRAULIC TANK BREATHERS

The hydraulic tank breathers (2, Figure 3-13) maintainatmospheric pressure inside the hydraulic tank as oilis pumped from and returned to the tank.

Hydraulic system malfunctions such as overheating,erratic operation, and pump failure can result if truck isoperated with plugged or restricted breathers. Be surethat breathers are kept clean and are not covered withmud or debris.

The breathers are replaceable assemblies that shouldbe changed at 1000 hour intervals under normal oper-ating conditions.

DUAL HYDRAULIC FILTERSTwo oil filters are located behind the left front tire asshown in Figure 3-14. Oil is filtered through 12 micronfilters to remove contamination from the system andreduce the possibilities of large particles damagingsystem components.

Included in the front filter assembly is a differentialpressure (∆P) switch to indicate when oil passingthrough the filter element is restricted. The differentialpressure switch is factory preset to actuate at 35 ± 5psi (241 ± 35 kPa) and is designed to give the operatoran alert before the filter begins to by-pass. Actual filterby-pass will occur at 50 psi (345 kPa).

NOTE: Upon start-up with cold oil, the restrictioncaused by cold oil may cause the warning indicatorlight to turn on. Hyraulic oil should be warmed up tonormal operating temperature before using thewarning light as an indicator to change elements.

The filter elements should be changed every 250 hoursor when the warning light comes on.

Premature filter restriction may indicate a system com-ponent failure and signal a service requirement beforeextensive secondary damage can occur.

FIGURE 3-14. FILTER INSTALLATION

1. LH Frame Rail2. Filter Assemblies

3. Front Suspension


Removal

Relieve pressure before disconnecting hydraulicand other lines. Tighten all connections beforeapplying pressure.


The following instructions are applicable to either filterassembly. Only the front filter is equipped with a differ-ential pressure switch.

1. With engine shut down and key switch ‘‘Off’’, allowat least 90 seconds for the accumulator to bleeddown.

Take care to avoid contact with hot oil if truck hasbeen operating. Avoid spillage and contamination!

2. Remove rotolock and bowl (8, Figure 3-15) andelement (7) and drain the oil from the filter housinginto a suitable container. Remove filter element (7)from bowl.

3. Before discarding element (7), inspect closely.Evidence of debris may signal a component prob-lem within the system.

4. Remove O-ring (5) in filter head and discard.

Installation

1. Install new O-ring (5) in filter head (4) and checkfor new O-ring (6) on new filter element (7).

2. Install new filter element (7) in rotolock and bowl(8). Install complete assembly onto filter head (4)and tighten securely.

NOTE: The differential pressure switch (1, Figure 3-15)and the warning light circuit it activates should betested periodically for proper operation. Refer to thefollowing instructions and equipment necessary totest differential pressure switch.

FIGURE 3-15. FILTER ASSEMBLY

1. Differential Pressure Switch2. O-Ring3. O-Ring4. Filter Head Assembly

5. O-Ring (Head) 6. O-Ring (Element) 7. Filter Element 8. Rotolock and Bowl


DIFFERENTIAL PRESSURE SWITCHTESTING

The differential pressure switch and warning light cir-cuit should be routinely tested as a part of the regularvehicle preventative maintenance. Figure 3-16 showsa pressure switch tester and Figure 3-17 shows a testblock to accept the switch during testing. The testblock may be fabricated as shown.

Test Procedure:

1. Remove differential pressure switch from filterhead and install in test block or pressure switchtester.

2. Reconnect wiring harness to switch.

3. Pump up pressure to test block and watch forwarning light indication.

4. Differential Pressure switch should turn on warninglight at 35 ± 5 psi (241 ± 35 kPa).

If the differential pressure switch does not operatewithin the specified range, replace the complete com-ponent. Switch adjustment is not recommended.

FIGURE 3-16. PRESSURE SWITCH TESTER

Kent-Moore Part Number--J-33884-4

FIGURE 3-17. DIFFERENTIAL PRESSURE SWITCH TEST BLOCK


FIGURE 3-18. INDICATOR LIGHT TEST WIRING HARNESS

Male Electrical Connector (on switch):

MS3102R-10SL-3P (revised)

Female Mating Electrical Connector:

MS3106-A10SL-3S (straight plug)or

MS3108-A10SL-3S (90° angle plug)

The following information is provided to assist in making (if desired)a temporary wiring harness for testing purposes.


NOTES


STEERING CIRCUIT

STEERING CIRCUIT OPERATIONOil from the outlet port of the steering/brake pump isdirected to both the accumulator oil supply manifoldand the auxiliary manifold. Oil going to the auxiliarymanifold is used for control functions. Oil going to theaccumulator supply manifold passes through themanifold and through the three check valves to fill thesteering accumulator and the two brake accumulators.Oil from the steering accumulator is directed to thesteering valve inlet port and steering bleeddown sole-noid valve located on the brake manifold. With theengine running and no movement of the steeringwheel, oil flow is blocked. When the engine is firststarted, the Emergency Steering warning light andalarm will be on until steering circuit pressure reaches1800 psi (12.5 MPa). Steering circuit pressure will con-tinue to increase until 2750 ± 50 psi (19.25 ± 0.35 MPa)maximum circuit pressure is reached.

When the steering wheel is turned, the attached steer-ing control valve directs oil from the steering accumu-lator to the steering cylinders. As circuit pressuredrops, pump flow increases, supplying oil to the accu-mulator to be directed to the rod end of one steeringcylinder and head end of the other cylinder. The otherport of each cylinder is connected through the steeringvalve to the tank. When oil flow to the steering cylindersis stopped by the steering control valve, circuit pres-sure increases again to maximum.

If the pump supply is removed while the truck is oper-ating, the accumulator will supply oil for steering untilthe truck can be stopped. As steering circuit pressuredecreases, the steering system pressure switch closesat 1800 psi (12.6 MPa), turning on the warning light andalarm on the instrument panel, warning the operator.

When shutting down the engine, turning off the keyswitch activates a timer that energizes the solenoid ofthe normally closed bleeddown valve. The valve isopen for 90 seconds allowing nitrogen to force oil outof accumulator back to tank. Refer to the HydraulicSchematic in Section "R".

STEERING CIRCUIT COMPONENTDESCRIPTION

STEERING CONTROL VALVE

The steering control valve (Figure 4-1) is mountedbelow the floor of the cab. Rubber mounting bushingsare utilized to minimize noise and vibration. The steer-ing column is connected to the valve through a vibra-tion isolation coupling.

The unit consists of a rotary directional valve andgerotor. The directional valve is closed center, blockingthe cylinder ports and inlet port from tank. The spoolof the directional valve is connected to the steeringwheel through the steering column. The control sleeveof the unit is linked to a gerotor. Leaf springs are locatedbetween the spool and sleeve to center the two whensteering wheel rotation stops.

Turning the steering wheel in either direction rotatesthe spool in relation to the sleeve allowing supply oil tothe gerotor. Supply oil drives the gerotor which deliversoil back through the sleeve and out to the steeringcylinders. Return oil from non-pressurized cylinderports return through the sleeve and back to tank. Aslong as the steering wheel is rotated, the gerotor andsleeve are trying to catch up to the spool. When steer-ing wheel rotation stops, the spool and sleeve return tocenter shutting off oil to the gerotor and stopping flowto the steering cylinders.

FIGURE 4-1. STEERING CONTROL VALVE

L04015 6/90 Steering Circuit L4-1

STEERING PUMP

The steering pump is a variable displacement, radialpiston pump. Inlet oil enters through the inlet port (11,Figure 4-2) in the pump housing (6). A common inletgallery (4) in the pump housing provides oil to eightinlet valves (5). Pistons (10) radially surround an eccen-tric cam. The cam uses a bearing race (3) upon whichthe pistons ride. Behind each piston is a spring whichpushes in and holds pistons against the bearing race.As the pump shaft (2) rotates, a low pressure cavitydevelops in the piston spring area during the down-ward stroke of the piston. This low pressure allows theinlet valve to open, filling the piston cavity with oil. Theinlet valves close at the end of inlet stroke of pistons.High pressure oil is developed as the race pushes thepistons outward. As pressure increases, the outletvalve (9) opens, allowing circuit pressure oil to passinto the outlet gallery. At the end of the stroke, circuitpressure oil in the outlet gallery closes the outlet valve.

All outlet valves share a common outlet gallery in thepump housing. An orifice (1) is located between thecrankcase and the inlet gallery. Any oil leakage past thepistons is routed through this orifice to the inlet gallery.This flow allows for cooling and lubrication. The pumpis designed to provide ‘‘On Demand’’ circuit pressureoil regardless of flow requirements. As demand for oildecreases, circuit pressure increases. This increasedpressure closes the crankcase outlet valve (7) and thenopens the stroke control valve (8) allowing high pres-sure oil to dump into the crankcase as maximum circuitpressure is reached. Increased pressure in the crank-case overcomes piston spring pressure and holds thepistons away from the race, thereby destroking thepump.

FIGURE 4-2. BRAKE/STEERING PUMP ASSEMBLY

1. Orifice2. Shaft3. Bearing Race4. Inlet Oil Gallery

5. Inlet Valve6. Pump Housing7. Crankcase Outlet Valve8. Pressure Compensator Valve

9. Discharge Valve10. Piston11. Oil Inlet Port

L4-2 Steering Circuit L04015 6/90

Pressure Compensator

The pump contains a stroke control valve (pressurecompensator) housing (1, Figure 4-3). The stroke con-trol valve housing is connected to the pump inlet gallery(2), outlet gallery (3), and pump crankcase (4 and 5).The stroke control valve (6), working with the crank-case outlet valve (7), maintains circuit pressure undervarying flow demands. Circuit pressure oil enters atpoint (3) and flows to the center section of the strokecontrol valve. At full pump stroke, crankcase pressureis at inlet pressure. As demand for circuit oil decreases,circuit pressure will begin to increase, causing crank-case the outlet valve (7) to close (move downward).This blocks the pump crankcase oil (4) from the inletgallery (2) except for any oil which passes through thecrankcase orifice. As maximum circuit pressure is ap-proached, the stroke control valve (6) opens (movesdownward) and allows circuit pressure oil into thecrankcase.

As circuit pressure rises further, more oil enters thecrankcase than can flow through the orifice. Crankcasepressure increases to slightly higher than inlet pressureovercoming the combined spring force on the pumppistons. The pistons are then held away from the pumpshaft bearing race destroking the pump. The pumpshaft continues to rotate, but the pistons travel onlyenough to supply flow through the crankcase.

As demand for circuit oil increases, circuit pressure willdecrease closing the stroke control valve. Oil will nolonger be routed to the crankcase. Crankcase pressurebegins to decrease as oil flows through the crankcaseorifice. When circuit pressure decreases sufficiently,the crankcase outlet valve (7) opens (moves upward)rapidly dumping the pump crankcase. The pump pis-ton springs overcome the decreased crankcase pres-sure and the pistons again come in contact with theshaft bearing race putting the pump into stroke.

STEERING ACCUMULATOR

The steering accumulator is a floating piston type withnitrogen on top of the piston. Oil from the steer-ing/brake pump enters the accumulator through acheck valve and fills the bottom of the accumulator untilpressure on the nitrogen side of the piston equalsmaximum circuit pressure established by the compen-sator of the steering/brake pump. The outlet port isconnected to the steering control valve. The top of theaccumulator contains a nitrogen charge pressureswitch and a nitrogen charging valve.

STEERING BLEEDDOWN SOLENOID VALVE

The bleeddown solenoid valve is a normally closedvalve mounted on the brake manifold. The solenoid isenergized by a timer that is turned on when the keyswitch is turned ‘‘Off’’ and engine shut down. The timerenergizes the solenoid for 90 seconds, allowing oil inthe bottom of the accumulator to return to tank whenthe truck is shut down.

STEERING PRESSURE SWITCH

The steering pressure switch turns on a warning lightand alarm on the instrument panel when steering cir-cuit pressure is below 1800 psi (12.5 MPa).

STEERING CYLINDERS

Double acting cylinders are connected between theframe rails and each front spindle.

FIGURE 4-3. STROKE CONTROL VALVE1. Housing 5. Pump Crankcase2. Pump Inlet Gallery 6. Stroke Control Valve3. Outlet Gallery 7. Crankcase Outlet Valve4. Pump Crankcase

L04015 6/90 Steering Circuit L4-3

NOTES

L4-4 Steering Circuit L04015 6/90

STEERING CONTROL VALVERemoval

1. Shut down engine and bleed down steering circuit.Allow at least 90 seconds for system to bleed.Open the manual bleeddown valves to releasethe pressure from the brake accumulators.

NOTE: To insure the hydraulic oil has completelydrained from the accumulator, turn the steering wheel.If the wheels do not turn, all the hydraulic pressure hasbeen drained from accumulator.

2. Clean exterior of steering control valve thor-oughly.

3. Tag and disconnect hydraulic lines. Plug lines andports securely to prevent spillage and possiblecontamination to the system.

4. Remove capscrews at flange (3, Figure 5-1).Remove nuts (6), washers (7 & 8) and capscrewat each rubber bushing. Lower and remove valve.

Installation

1. Assemble steering control valve (10, Figure 5-1)to mounting plate (11). Insert assembly throughbottom of cab floor and align splines on valvecolumn (4) with the flange assembly (3). Installcapscrews (9), from bottom side of mountingplate, through the rubber bushings (12). Installflatwashers, lockwashers and nuts. Tighten tostandard torque.

2. Install capscrews in flange (3) and tighten tostandard torque.

3. Remove caps from hydraulic lines. Be certain thatpreviously tagged lines are connected to theirrespective ports according to the markings on thesteering control valve assembly.

Ports on steering control valve are marked:

‘‘T’’ - Tank (Return to tank) - Upper Left Port

‘‘L’’ - Left Steering Cylinder - Upper Right Port

‘‘P’’ - Pressure (In from Pump) - Lower Port *


1. Universal Joint2. Stub Shaft3. Flange & Isolator4. Steering Valve Column5. Mounting Plate6. Nut

7. Lockwasher 8. Flatwasher 9. Capscrew10. Steering Control Valve11. Valve Mount Plate12. Rubber Bushing

FIGURE 5-2. INLINE FILTER INSTALLATION

1. Steering Control Valve 2. Filter

L05009 5/98 Steering Control Valve L5-1

‘‘R’’ - Right Steering Cylinder - Lower Port *

* See ‘‘NOTE’’ on next page.

NOTE: HAULPAK®trucks use an inline filter to pro-vide additional protection to the steering control unit(see Figure 5-2). This filter must be installed in the portmarked ‘‘P’’ on the steering control housing.

Serious personal injury to the Operator or to any-one positioned near the front wheels may occur ifa truck is operated with the hydraulic steering linesimproperly installed. Improperly installed linescan result in uncontrolled steering and SUDDENAND RAPID rotation of the steering wheel as soonas the steering wheel is moved. It will turn rapidlyand cannot be stopped manually.

After servicing the steering control assembly, hy-draulic steering lines should be checked for cor-rect hook-up before starting the engine.

Disassembly

Tools required for disassembly and assembly:

• 2 - Screwdrivers [4-6 in. (100-150 mm) long, 1/8 in. (3 mm) flat blade]

• 1/2 inch Socket (12 point)

• Breaker Bar Wrench

• Torque Wrench, 90 ft. lbs. (120 N.m) Capacity

• Plastic Hammer or Rubber Hammer

• Tru-Arc Retaining Ring Pliers

The tool shown in Figure 5-3 is not necessary fordisassembly and assembly, but is extremely helpful.

NOTE: The steering control valve is a precision as-sembly manufactured to very close tolerances, there-fore complete cleanliness is a must when handlingcontrol valve. Work in a clean area and use lint freewiping materials or dry compressed air. Use a wirebrush to remove foreign material and debris fromaround exterior joints of valve before disassembly.Fresh solvent and Type C-4 oil should be used toinsure cleanliness and initial lubrication.

NOTE: Although not all drawings show the controlvalve in a vise, the valve housing should be kept in thevise during disassembly. Follow the clamping proce-dures explained throughout the procedure.

1. Clamp control valve in vise, meter end up. Clamplightly on edges of mounting area (See Figure5-4).

Use protective material on vise jaws and DO NOTovertighten jaws.

2. Remove capscrews (18, Figure 5-5) from end cap(17). Remove end cap.

FIGURE 5-3. SPRING INSTALLATION TOOL FIGURE 5-4. CLAMPING VALVE ASSEMBLY

L5-2 Steering Control Valve L05009 5/98

3. Remove seal (16) from meter (15). Remove meterbeing careful not to drop the star from inside ofmeter.

4. Remove seal (9) from meter (15).

5. Remove wear plate (21).

6. Remove seal (9) from housing (8).

7. Remove drive (14).

8. Remove housing from vise. Place housing on aclean soft cloth to protect the finish. Use Tru-Arcretainer ring pliers and remove retaining ring fromhousing, as shown in Figure 5-6.

9. Position screwdrivers 180° apart in groove ofretainer. (See Figure 5-7). Pry retainer upwarduntil flush with housing. Be careful not to damagering groove of front retainer. Remove screwdriv-ers and push spool down while removing retainerfrom housing by hand.

10. Remove teflon seal (20, Figure 5-5), O-ring seal(5), backup ring (19), O- ring seal (4) and dust seal(2) from front retainer (3).

11. Remove bearing races (6) and the needle thrustbearing (7) from spool and sleeve assembly.

FIGURE 5-5. STEERING CONTROL VALVE ASSEMBLY

1. Retaining Ring2. Dust Seal 3. Front Retainer4. O-ring Seal5. Seal6. Bearing Race

7. Needle Thrust Bearing 8. Housing 9. Seal10. Control Spool11. Centering Springs

12. Control Sleeve13. Pin14. Drive15. Meter (Gerotor)16. Seal

17. End Cap18. Capscrew19. Backup Ring20. Teflon Seal21. Wear Plate


Avoid binding spool and sleeve in housing. A veryslight back and forth rotation of spool and sleevehelps reduce binding. Keep pin in a nearly horizon-tal position when removing spool and sleeve fromhousing. If pin becomes vertical during removal, itmay drop from spool and sleeve into an oil pas-sage inside the housing.

12. Remove spool and sleeve assembly (10 & 12) frommeter end of housing. (See Figure 5-5). Push pin(13) from spool and sleeve assembly.

13. Remove spool from sleeve and then carefullyremove eight centering springs from spool. (SeeFigure 5-9).

FIGURE 5-6. RETAINER RING REMOVAL

FIGURE 5-7. FRONT RETAINER REMOVAL

FIGURE 5-8. SPOOL, SLEEVE & PIN REMOVAL

1. Spool & Sleeve 2. Pin

FIGURE 5-9. SPOOL AND SLEEVE

1. Spool2. Centering Springs

3. Sleeve



1. Clean all mating surfaces. Replace any parts thathave scratches or burrs, or show signs of wear.

2. Clean all metal parts with clean solvent such asTrichlorethylene, Acetone or Lacquer Thinner.Spool and sleeve in this unit have been machinedto very close tolerances and any foreign materialmay be damaging.

When using cleaning agents follow solvent manu-facturers warnings.

3. Blow dry with air. DO NOT wipe dry with cloth orpaper towel. Lint or other foreign material couldget into the hydraulic system and cause damage.

4. DO NOT use grit or try to file or grind steeringcontrol unit parts.

5. Lubricate all seals (except new quad ring seal)with clean petroleum jelly, such as Vaseline. Donot use excessive lubricants on seals for metersection.

NOTE: Refer to Parts Catalog when ordering replace-ment parts. A good service policy is to replace all oldseals with new seals whenever unit is disassembled.

Assembly

1. Assemble spool and sleeve carefully so that thecentering springs slots line up.

2. Apply a light film of clean oil to the outside diame-ter of the spool. Rotate spool while sliding partstogether.

Because of close tolerances between spool andsleeve, DO NOT use force when rotating partstogether. Be careful not to burr the sleeve.

3. Test for free rotation. Spool should rotatesmoothly in sleeve with finger tip force applied atsplined end.

4. Align spring slots of spool and sleeve, then standparts on bench. Insert spring installation tool (seeFigure 5-3) through spring slots of both parts.

NOTE: If spring installation tool is not available, useAlternate Method, as described below.

5. Position centering springs (two sets of four each)on the bench so that the extended edge is downand center section is together.

6. In this position, insert one end of the entire springset into spring installation tool (Figure 5-10).

7. Compress expanded end of centering spring setand push into spool and sleeve assembly. Keeppressure on spring ends when withdrawing instal-lation tool, push forward on spring set at the sametime.

8. Center spring set in spring slots. Seat springsdown evenly and flush with upper surface of thespool and sleeve.

Alternate Method:

Carefully follow these instructions when installing cen-tering springs without the aid of a spring installationtool:

a. Insert one centering spring, with extendededge down, in spring slot of spool (raise spoolfrom sleeve slightly for more spring clearance).

b. Insert one centering spring opposite springlocated in slot spool. Make sure center sectionof both springs are together and that the ex-tended edge of the springs are down.

FIGURE 5-10. CENTERING SPRINGSINSTALLATION

1. Spring Installation Tool 2. CenteringSprings


c. Push one set of three centering springs be-tween the two springs in the spool (Figure5-10).

d. Push remaining set of three centering springsopposite four centering springs in spool.

e. Push spool in sleeve until springs seat flushwith top and sides of sleeve.

9. Install pin through spool and sleeve assembly untilpin becomes flush with both sides of sleeve.

10. Position spool and sleeve assembly so splined endof spool enters meter end of housing first (seeFigure 5-11).

Be extremely careful that spool and sleeve DOESNOT tilt out of position while inserting into hous-ing. Lubricate O.D. of sleeve. Push parts gentlyinto place with slight rotation. KEEP PIN HORI-ZONTAL. Bring the spool assembly entirely withinthe housing bore until the parts are flush at themeter end of housing. Do not pull the spool assem-bly beyond this point to prevent the cross pin fromdropping into the discharge groove of the housing.With the spool assembly in this flush position,check for free rotation within the housing by turn-ing with light finger force at the splined end.

11. Place housing on a clean lint free cloth (meter enddown). Install bearing races and needle thrustbearing (3 & 4, Figure 5-12).

12. Install dust seal (4, Figure 5-13) in front retainer,flat or smooth side of dust seal must face downtoward retainer. Install backup ring (19, Figure 5-5), O-ring seal (5) and teflon seal (20) in frontretainer. DO NOT use any seal that falls freely intopocket of retainer.

13. Install O-ring seal on front retainer.

14. Install front retainer (2, Figure 5-13) over the spoolend with twisting motion. Tap the retainer in hous-ing with a rubber hammer making sure retainer isseated flush on the bearing race.

15. Using Tru-Arc retaining ring pliers, install retainingring in housing (see Figure 5-13). After installingring, tap ring to make sure it is properly seated ingroove.

16. Clamp housing in vise. Install seal (9, Figure 5-5)in housing.

FIGURE 5-11. SPOOL AND SLEEVE

FIGURE 5-12. BEARING INSTALLATION

1. Retaining Ring2. Front Retainer (with

Seals)

3. Needle ThrustBearing

4. Bearing Race


Do not overtighten jaws when clamping valvehousing in vise. Clamp lightly on edges of mount-ing area.

17. Rotate spool and sleeve assembly until pin isparallel with port face (Figure 5-14). Install drive(2), making sure drive is engaged with pin (3).

NOTE: To assure proper alignment, mark one of thetwo drive tooth slots that are parallel with slot in theend of drive (see Figure 5-15, Reference B & C).

A timing mark made on drive must fall on theparallel line between any two meter star valleys.Note the parallel relationship of reference lines A,B, C and D (Figure 5-15 & 5-16).

NOTE: Check to insure that the spool and sleeve areflush or slightly below the meter end of the housing.Clean the upper surface of the housing by wiping withthe palm of a clean hand. Clean each of the flatsurfaces of the meter end parts in a similar way whenready for reassembly. DO NOT use cloth or papertowel to clean surfaces.

FIGURE 5-13. RETAINER INSTALLATION

1. Retaining Ring2. Front Retainer3. Seal

4. Dust Seal5. O-ring Seal6. Thrust Bearing

FIGURE 5-14. DRIVE AND PIN INSTALLATION

1. Port Face2. Drive

3. Pin

FIGURE 5-15. GEROTOR TIMING

1. Star Meter Valley (Gerotor)2. Drive Marked As Shown

3. Pin


18. With seal groove side of meter down, install meteron drive (Figure 5-16).

19. Align bolt holes without disengaging meter fromdrive. Carefully adjust meter on housing, exces-sive turning of meter may disrupt seal betweenmeter and housing.

20. Install seal (16, Figure 5-5) in meter. Install endcap on meter. Carefully align holes as not todisrupt seal from meter.

21. Install lubricated capscrews in end cap. Tightencapscrews to 15-20 ft.lbs. (20.3-27.1 N.m)torque, then torque screws to 75 ft.lbs. (100 N.m)torque. Pretighten and torque capscrews in ordershown. (Figure 5-17).

22. Apply a small amount of LW025-27multi-purposemoly grease to the internal splines of the spool (1,Figure 5-9).

FIGURE 5-16. GEROTOR ORIENTATION

1. Port Face2. Meter (Gerotor) Star Valley3. Pin

4. Housing5. Meter (Gerotor) Star6. Drive Spline

7. Drive8. Wear Plate

FIGURE 5-17. TIGHTENING SEQUENCE


STEERING CIRCUIT COMPONENT REPAIR

ACCUMULATORS

The following removal, installation, disassembly andassembly procedures are applicable to both the steer-ing and brake accumulators.

Do not loosen or disconnect any hydraulic line orcomponent connection until engine is stoppedand keyswitch has been ‘‘Off’’ for at least 90 sec-onds.


Removal

1. Block the wheels of the truck.

2. Insure key switch has been ‘‘Off’’ for at least 90seconds to allow accumulator oil to drain back totank. Check by turning steering wheel.

3. Bleed the pressure from the brake accumulatorsby turning the bleeder valves (4, Figure 6-2) lo-cated on the Low Brake Pressure Detection Mod-ule (5) counterclockwise. When the accumulatorsare completely bled down, close bleeder valvesby turning the bleeder valve handles clockwise.Do not leave valves open.

FIGURE 6-1. ACCUMULATOR INSTALLATION

1. Steering Accumulator2. Rear Brake Accumulator3. Cover4. Front Brake Accumulator

5. Front Bumper6. Low Brake Pressure

Detection Manifold7. Accumulator Oil

Supply Manifold

FIGURE 6-2. ACCUMULATOR PIPING

1. Steering Accumulator2. Rear Brake Accumulator3. Front Brake Accumulator4. Brake Accumulator Bleed

Valves5. Low Brake Pressure

Detection Manifold

6. Pressure Test Port 7. Low Brake Pressure

Switch 8. Oil Supply Hose 9. Manifold10. Check Valves

L06007 5/92 Steering Circuit Component Repair L6-1

4. Remove charging valve cover (3, Figure 6-1).

Make certain only the small swivel hex nut turns.DO NOT TURN MORE THAN THREE TURNS. Turn-ing the complete charging valve assembly mayresult in the valve assembly being forced out of theaccumulator by the nitrogen pressure inside.

Wear protective face mask when discharging nitro-gen gas.

5. Remove charging valve cap and loosen small hexon charging valve (3, Figure 6-3) three turns.Depress the valve core until all nitrogen pressurehas been relieved.

6. Remove oil lines from bottom of accumulator. Plugall hoses and openings to prevent possible con-tamination of the system. Disconnect and markelectrical wiring to pressure switch (1).

7. Attach a handling device to the accumulator.

8. Remove nuts and lockwashers securing the accu-mulator mounting straps (5, Figure 6-3) to themounting bracket.

9. Remove accumulator from the mounting bracketand move to a clean work area for disassembly.

Installation

1. Lift accumulator into position on the mountingbracket. Accumulator should be positioned withthe warning label positioned to the rear of thetruck.

2. Secure the accumulator to the mounting bracketusing mounting straps, lockwashers and nuts. Donot overtighten nuts, as this could distort theaccumulator.

3. If pressure switch was removed, install at this time.Connect electrical wiring to pressure switch andreconnect oil lines to the bottom of the accumu-lator.

4. Precharge accumulator with pure dry nitrogen asoutlined in ‘‘Accumulator Charging Procedure’’.

Disassembly

1. Remove charging valve (1, Figure 6-4).

2. Use a spanner wrench to remove head (2) at topof accumulator.

3. Push piston (8) out of Housing (5).


1. Replace O-rings (4, Figure 6-4), backup ring (3)and ‘‘T’’ ring (7).

2. Clean parts using fresh cleaning solvent, lint freewiping cloth and filtered compressed air. All partsmust be absolutely free of any foreign matterlarger than 3 microns.

3. Check piston bearings (6) for excessive wear.

4. Minor defects may be corrected by lapping orstoning. Clean parts to remove abrasive residueafter lapping or stoning.

Assembly

Assemble the accumulator in a dust and lint free area.Maintain complete cleanliness during assembly to pre-vent possible contamination.

1. Lubricate all components with clean Type C-4hydraulic oil.

FIGURE 6-3. ACCUMULATOR CHARGING VALVE

1. Low AccumulatorPressure Switch

2. Charging Valve

3. Small Hex Nut4. Accumulator5. Mounting Strap

L6-2 Steering Circuit Component Repair L06007 5/92

2. If bearings (6, Figure 6-4) need replacing, specificbonding instructions are required to properly re-place the bearings. If replacement is necessarycontact the HAULPAK® Distributor for proper pro-cedure.

3. Install ‘‘T’’ ring (7) on piston and install the pistonwith the concave side toward gas end of accumu-lator cylinder housing (5).

4. Install new O-ring (4) and new backup ring (3) onthe head (2). Backup ring should be positionedtoward threads on head.

NOTE: Pour 24 oz. (710 ml) of LW102-30 Rust Preven-tive Oil in the gas end of the accumulator. This willinsure a gas tight seal between each end of the accu-mulator.

5. Install head (2) on the housing (5) and tighten to500 ft.lbs. (678 N.m) torque.

6. Install charging valve (1) with a new lubricatedO-ring. Tighten charging valve large hex nut to16.5 ft.lbs. (22.3 N.m) torque.

LOW PRESSURE ACCUMULATORPRESSURE SWITCHOne switch is located in the top of each accumulator.A normally closed (N/C) switch, it has contacts set toclose at 850 psi (5861 kPa) decreasing pressure. Whenclosed, it provides ground for precharge relay coil andwarning light. The three pressure switchs are con-nected together in parallel and will actuate the dashmounted pre-charge light when a switch is defective oraccumulator is not precharged correctly.

Check for defective pressure switch as follows:

1. Engine stopped.

2. Accumulator oil pressure bled down.

3. Key turned "ON" and precharge light "ON".

4. Key turned "OFF".

5. Disconnect one switch on a accumulator.

6. Key turned "ON", if light does not come on, thisis the accumulator with low nitrogen pressureor a, defective pressure switch. If light comeson repeat steps 4, 5, & 6 by disconnectingadditional switches until the accumulator withlow nitrogen pressure or a, defective pressureswitch is found.

7. Check nitrogen pressure with charging kit.Charge accumulators if necessary or replacedefective pressure switch.

8. Key "Off". Reconnect all disconnected pressureswitches.

FIGURE 6-4. ACCUMULATOR ASSEMBLY

1. Charging Valve2. Head3. Backup Ring4. O-Ring

5. Housing Structure6. Bearings7. ‘‘T’’ Ring8. Piston


ACCUMULATOR CHARGING PROCEDURE

The following procedures are applicable to both thesteering system and the brake system accumulators.

Do not loosen or disconnect any hydraulic line orcomponent until engine is stopped, key switch hasbeen ‘‘Off’’ for at least 90 seconds and brake accu-mulators are bled.

Pure dry nitrogen is the only gas approved for usein the accumulators. The accidental charging ofoxygen or any other gas in this compartment maycause an explosion. Be sure pure dry nitrogen gasis being used to charge the accumulator.

When charging or discharging the nitrogen gas inthe accumulator, be certain the DANGER andWARNING labels are observed and the instructionsregarding the charging valve are carefully read andunderstood.




NOTE: If a loss in nitrogen pressure occurred duringoperation, oil may still be present in the accumulatorbelow the piston. This oil can be bled off during thenitrogen charging procedure. If the steering accumu-lator is being charged, turn the steering wheel backand forth or actuate the bleed down solenoid by turn-ing the key switch ‘‘On’’ and then ‘‘Off’’. If a brakeaccumulator is being charged, open the appropriatebleeder valve during initial charging. Close thebleeder valve after pressure has forced the piston tothe bottom of the housing.

4. Remove charging valve guards.

If nitrogen pressure is present in the accumulator,make certain only the small swivel hex nut is turnedduring the next step. DO NOT TURN MORE THANTHREE TURNS. Turning the complete valve assem-bly may result in the valve assembly being forcedout of the accumulator by the nitrogen pressureinside.

5. Remove charging valve cap (1, Figure 6-5). Turnsmall swivel hex nut (4) three complete turnscounterclockwise.

6. Insert the tip of a screwdriver against the chargingvalve stem and depress stem. Hold down until allnitrogen has been released.

7. If a loss in nitrogen pressure is the reason forrecharging, inspect the charging valve and accu-mulator for damage. Replace or repair items, asnecessary, before attempting charging proce-dure.

8. Connect the nitrogen charging kit to the chargingvalve. Open the regulator and charge the accu-mulator to 1050 psi (7.2 MPa).


1. Valve Cap2. Seal3. Valve Core4. Swivel Nut5. Rubber Washer

6. Valve Body7. O-Ring8. Valve Stem9. O-Ring


NOTE: When charging the accumulator, allow ade-quate time for the system to fully charge. Insure all oilhas returned from the accumulator to the hydraulictank.

9. Shut off charging kit and check pressure gaugereading. If gauge does not maintain 1050 psi (7.2MPa) continue charging procedure until pressureis stabilized.

10. Remove the charging kit and tighten small hex nuton charging valve to 4 ft.lbs. (5.4 N.m) torque.

NOTE: If a new charging valve was installed, the valvestem must be seated as follows:

a. Tighten small hex swivel nut to 10.5 ft.lbs. (14.2N.m) torque.

b. Loosen swivel nut.

c. Tighten swivel nut to 10.5 ft.lbs. (14.2 N.m)torque.

d. Again, loosen swivel nut.

e. Finally, tighten swivel nut to 4 ft.lbs. (5.4 N.m)torque.

11. Install charging valve cap (1) and tighten fingertight. Install charging valve guard and tighten cap-screws to 25 ft.lbs. (40 N.m) torque.

12. Operate truck and check steering and brake sys-tem operation.

INLINE FILTERSTwo inline hydraulic oil filters (Figure 6-6) are used onthe Haulpak® truck. One filter is located at the inlet portof the steering control valve (‘‘P’’ port). The other filteris located at the the branch of the ‘‘Tee’’ supplying oilto the brake/steering pump. This ‘‘Tee’’ is inside theright hand frame rail, above the steering pump.

Service

The inline filters should be serviced at 5000 hour inter-vals or sooner if contamination of the hydraulic systemis suspected.




4. Disconnect hose attached to filter. Remove filter.

5. Clean the filter in fresh solvent and dry with com-pressed air.

6. Inspect the filter disc for trapped contaminants ordamage. If filter disc cannot be be cleaned asabove or appears damaged, discard assemblyand replace with a new part.

7. Install filter using a new O-ring if necessary. Attachhose and tighten securely.

8. After the engine has been started, inspect connec-tions and repair leaks if found. Service the hydrau-lic tank, if necessary.

FIGURE 6-6. INLINE HYDRAULIC OIL FILTER


STEERING CYLINDERSThe steering cylinders are mounted to the spindle andframe on ball studs to allow for angular movement asthe front wheels turn and the steering cylinders extendand retract. Removal and installation and ball studreplacement instructions can be found in Section ‘‘G’’.

Disassembly

1. Use a spanner wrench and remove gland (6,Figure 6-7). Pull rod (11) and gland out of housing(1).

2. Remove locknut (2) and piston (3). Remove pistonbearing (4) and piston seal (5) from piston.

3. Pull rod (11) free of gland (6). Remove O-ring (7)and backup ring (8). Remove rod seal (9) and rodwiper (10).

4. Inspect cylinder housing, gland, piston and rod forsigns of pitting, scoring or excessive wear. Cleanall parts with fresh cleaning solvent.

Assembly

1. Lubricate all internal parts with type C-4 oil beforeassembly.

2. Install new rod seal (9, Figure 6-7), rod wiper (10),backup ring (8) and O-ring (7) in gland (6).

3. Push rod (11) through top of gland, slowly advanc-ing rod over rod seal and rod wiper.

4. Install seal assembly (5) as follows:

a. Place piston (3) on workbench with seal grooveat top. Install O-ring.

b. Heat seal several minutes in boiling water.

c. Remove seal ring from water and install Imme-diately. (Ring will take a permanent set in ap-proximately 5 seconds.) If seal has taken aslightly large set, tighten using a piston ringcompressor.

5. Install new bearing (4) on piston (3). Secure pistonto rod with locknut (2). Tighten locknut to 850ft.lbs. (1153 N.m) torque.

6. Carefully install rod and gland assembly into hous-ing (1). Insure backup ring (8) and O-ring (7) arenot damaged during installation of gland.

7. Using a spanner wrench, tighten gland to 500ft.lbs. (675 N.m) torque.

FIGURE 6-7. STEERING CYLINDER

1. Housing2. Locknut3. Piston4. Bearing

5. Seal Assembly6. Gland7. O-Ring

8. Backup Ring 9. Rod Seal10. Wiper11. Rod


BRAKE/STEERING PUMP REPAIR

Removal



3. Bleed the pressure from the brake accumulatorsby turning the bleeder valves located on the LowBrake Pressure Detection Module counterclock-wise. When the accumulators are completely bleddown, close bleeder valves by turning the bleedervalve handles clockwise. Do Not leave valvesopen.

Escaping fluid under pressure can penetrate theskin causing serious injury and possibly death ifproper medical treatment by a physician familiarwith this type of injury is not received immediately

Relieve pressure before disconnecting hydraulicor other lines. Tighten all connections before ap-plying pressure.

4. Loosen the vent plugs above the suction andreturn tubes on the hydraulic tank.

5. Clean dirt accumulation from the pump and PTOdrive area.

6. Remove inlet, outlet and drain hoses from pump(2, Figure 6-8). Cap all lines to prevent possiblecontamination.

7. Support pump, remove capscrews (1)and lock-washers securing pump to PTO (3).

8. Slide pump shaft out of PTO drive splines andremove.

Installation

1. Install a new O-ring in the bore of the pumpmounting flange.

2. Align pump (2, Figure 6-8) shaft splines with PTOdrive and slide pump into position against theadapter flange.

3. Install capscrews and lockwashers (1). Tighten tostandard torque.

4. Connect hoses to inlet, outlet and drain ports ofpump.

5. Close vent plugs in hydraulic tank cover. Refillhydraulic tank as required.

6. Refer to ‘‘Steering Circuit Checkout Procedure’’and adjust pump compensator pressure.’’

Disassembly

1. Thoroughly clean outside surface of pump.

2. Install pump on a bench fixture (Figure 6-9).

FIGURE 6-8. HYDRAULIC PUMPS

1. Capscrews & Lockwashers2. Brake/Steering Pump

3. PTO Drive4. Hydraulic Pump

FIGURE 6-9. PUMP REBUILD FIXTURE


3. Drain off excess hydraulic oil from pump inlet anddischarge ports.

4. Write or stamp numbers on pump housing, pistonplugs, and inlet valves for identification.

NOTE: Pistons must be installed in their original boresif they are reused.

5. Remove piston plugs (1, Figure 6-11), springs (2)and pistons (3).

6. Put assemblies in a parts tray to insure installationinto the same bores from which they were re-moved.

7. Install vice grips as tightly as possible on pumpshaft, approximately 0.625 in. (16mm) from hous-ing hub as shown in Figure 6-10.

NOTE: Use vice grip with curved jaw for better clamp-ing.

8. Check pump shaft end play as follows:

a. Place a magnetic base dial indicator on thepump housing with the indicator contact pointon a steel ball placed in center of pump shaft.

b. Turn the shaft back and forth while pushingdown to align the tapered roller bearings insidepump housing.

c. Zero the indicator.

d. Pry upward on the vice grips noting indicatorreading. If end play is more than specificationshown below, check bearings for wear.

End Play Specification

Acceptable . . . 0.001-0.004 in. (0.025-0.100 mm)

9. Check for damage to threaded area of piston plug(1, Figure 6-11).

10. Discard O-ring (2) and shield (3).

11. Inspect springs (4) for wear or damage.

The maximum difference of force permissible be-tween each of the eight springs (4) in a set is 1.5lb. (6.7 N). If difference is more than specification,install new springs as a set. The colored spring setsare interchangeable as sets; example: red canreplace yellow, blue can replace green, etc.

NOTE: Side movement of the springs during test maygive an erroneous reading.

12. Check compression rate of springs using a springcompression tester.

New Spring SpecificationFree Length (Approximate) . . . 2.44 in. (62 mm) Test Length at 34-40 lb. (151-178 N) . . . . . 1.62 in. (41.1 mm)

13. Inspect face and skirt of pistons (5) for metaltransfer, galling or scoring.

The pressure compensator valve housing andpump housing must be fastened together andtightened to specification before measurementcan be done on the piston bores.

NOTE: Tolerances indicated may be difficult to obtainwith normal micrometer measuring devices.

FIGURE 6-10. CHECKING END PLAY

1. Vise Grips 2. Dial Indicator


14. Check piston OD (‘‘A’’) and piston bore ID (‘‘B’’) asshown in Figure 6-12.

New Part SpecificationPiston OD . . . . . . 0.8740-0.8744 in. (22.2001-22.210 mm) Piston Bore ID . . . . 0.8749-0.8753 in. (22.223-22.233 mm)

FIGURE 6-11. BRAKE/STEERING PUMP ASSEMBLY

1. Plug (8)2. O-Ring (8)3. Shield (8)4. Spring (8)5. Piston (8)6. Snapring (1)7. Seal (1)

8. Fitting (8) 9. O-Ring (8)10. Valve (8)11. Valve Seat (8)12. O-Ring (1)13. Plug (1)14. Housing (1)

15. Disk (8)16. Spring (18)17. Guide (8)18. Stop (8)19. Valve Assembly (8)20. Bearing Cup (2)21. Bearing Cone (2)

22. Spacer (2)23. Thrust Washer (2)24. Sealing Ring (2)25. Shaft (1)26. Needle Roller (25)27. Bearing Race (1)28. Shim (as required)

NOTE: Parts quantities shownin parentheses ( ).

FIGURE 6-12. PISTON & BORE MEASUREMENT


IMPORTANT! Mark the pressure compensator valveand pump housing prior to disassembly. Proper align-ment is essential during assembly.

15. Mark the pressure compensator valve housing (15,Figure 6-13) and pump housing (14, Figure 6-11)to insure proper alignment during assembly.

16. Remove pressure compensator valve housing frompump. Save shims (28, Figure 6-11)) for reassem-bly.

17. Discard O-ring (5) and packings (16 and 17).

Outlet valve assemblies must be installed in theiroriginal bores.

18. Remove the eight outlet valve assemblies (19) andput them in a parts tray.

19. Remove pump shaft (25) assembly and outer bear-ing race.

20. Visually inspect taper bearing cones (21) for dam-aged cage or rollers.


FIGURE 6-13. PRESSURE COMPENSATOR ASSEMBLY

1. Plug (1)2. O-Ring (1)3. Fitting (1)4. O-Ring (1)5. Plug (1)6. Pin (1)7. O-Ring (1)8. Capscrew (4)

9. Valve (1)10. Spring (1)11. O-Ring (1)12. Plug (1)13. O-Ring (2)14. Plug (2)15. Housing (1)16. Packing (2)

17. Packing (8)18. O-Ring (1)19. Nut (1)20. Adjustment Screw (1)21. O-Ring (1)22. Bushing (1)23. O-Ring (1)24. Special Washer (1)

25. Spring (1)26. Guide (1)27. Control Valve (1)28. Backup Ring (1)29. O-Ring (1)30. O-Ring (1)31. Washer (1)32. Pressure Test Q.D.(1)


21. Visually inspect spacers (22) and thrust washers(23) for wear or damage.

22. Inspect race (27) for nicks, scratches, pitting ormetal discoloration. Replace race and pistons ifexternal damage exists.

23. Hold pump shaft (25) and slowly turn race (27). Ifassembly is sticking or noisy, replace needle roll-ers (26) between race and pump journal.

NOTE: Bearing cups must be used with same conefrom which they were removed.

24. Remove bearing cup (20) from pump housing (14).

NOTE: Pump housing, bearing cones and cups mustbe replaced if bearing cups show signs of spinning.

25. Inspect bearing cups (20) for damage.

26. Place bearing cups (20) on matching cone (21) andturn slowly. If bearings makes a clicking noise orare sticking, clean and dip cone in clean hydraulicoil. Turn again and replace if bearing continues toclick or stick.

27. Remove sealing ring (1, Figure 6-14).

NOTE: Bearing puller may have to be put under spacerto start bearing cone removal.

28. Remove bearing cones (1,Figure 6-15) using abearing puller (2).

29. Disassemble pump shaft.

30. Inspect shoulder surface of bearings (1) . Replaceif spacer wear exists.

31. Inspect spacers (22, Figure 6-11). Replace if worn,scored or discolored.

32. Refer to specifications chart Figure 6-33 and checkshaft (25) journal OD. Replace if pitted, scored ordiscolored.

NOTE: VESPEL® thrust washers may require magnifi-cation for inspection.

33. Inspect thrust washers (23). Replace if worn ordamaged.

NOTE: Refer to specifications chart, Figure 6-33 forneedle roller OD and race OD and ID.

34. Inspect race (27) on O.D. and I.D. Replace ifscored, discolored, or pitted.

35. Inspect needle rollers (26). Replace ALL if any arescratched, pitted, or discolored.

36. Inspect piston bores (2, Figure 6-16) in pumphousing (1). Replace housing and pistons if scor-ing, galling or metal transfer exists.FIGURE 6-14. SEALING RING REMOVAL

1. Sealing Ring 2. Shaft

FIGURE 6-15. BEARING CONE REMOVAL

1. Bearing Cone 2. Bearing Puller


37. After visual inspection, install each piston (3) intoits bore so it extends approximately 0.5 in. (13 mm)into crankcase. Pistons must slide smoothly andhave no side play. If any side play is found, replacehousing and pistons.

38. Remove inlet valve plugs.

39. Check inlet valves for free valve movement andvalve lift. If valves are not broken and move freely,do not remove (Figure 6-17).

New Part SpecificationInlet Valve Lift (Approximate) . . . 0.078-0.120 in. (2.0-3.0 mm)

NOTE: Removed inlet valves must be replaced withnew valves since press fit is critical for sealing.

40. If necessary, remove inlet valves as shown in Figure6-18.

41. Inspect outlet valve guide (17, Figure 6-11) forfatigue or damage.

42. Inspect outlet valves (15). Replace if wear, damage,or deep grooves exist.

43. Inspect springs (16) for wear or damage.

44. Check compression rate of springs using a springcompression tester.

New Spring Specification

Free Length (Approximate) . . 0.48 in. (12.2 mm) Test Length at 2.5-3 lb. (11-14 N) . . . . . . . 0.30 in. (7.6 mm)

45. Inspect outlet valve stops (18) for wear or damage.

46. Wipe outlet valve seats (1, Figure 6-19) with afinger, accessing seat through the outlet valvebores. This should be done before inspection,since oil on valve seat may give impression of seatdamage.

47. Visually inspect outlet valve seats (1) for peeningor damage.

NOTE: Because the press fit is critical for sealing, DONOT remove outlet valve seats unless replacement isabsolutely necessary. Removal and installation re-quires special tool.(John Deere Part Number JDH-39B-1)

FIGURE 6-16. PISTON BORE INSPECTION

1. Housing2. Piston Bores

3. Piston

FIGURE 6-17. CHECKING INLET VALVES

FIGURE 6-18. INLET VALVE REMOVAL

1. Inlet Valve 2. Housing


48. If valve seat replacement is necessary, install spe-cial screw (2) into seat through piston bore andinstaller and removal Tool (3) through outlet valvebore (Figure 6-19).

49. Install a slide hammer and adapter into the tool andremove seat.

50. Remove oil seal retaining snap ring.

51. Remove oil seal using a puller and slide hammer(Figure 6-20).

Assembly

1. Apply clean hydraulic oil on all internal parts beforeassembly.

DO NOT push oil seal beyond inner edge of snapring groove. Doing so can close drain passage andcause an oil seal failure.

2. Using a 1.94 in. (48 mm) diameter disk, press oilseal (7, Figure 6-11) with lip (spring side) towardinside of pump housing, making sure drain pas-sage is not blocked.

3. Apply petroleum jelly to lips of oil seal for lubrica-tion when shaft is installed.

4. Install retaining snap ring (6).

NOTE: Bearing cup (20) may be slip fit.

5. Install bearing cup (20) in housing using a 3.94 in.(84 mm) diameter disk and an arbor press.

Removed inlet valves must be replaced with newvalves since press fit is critical for sealing.

6. Install new O-rings (9) on inlet valve plugs (8).

7. Install inlet valve assemblies (1, Figure 6-21) usingvalve plugs to push inlet valves into their bores.

8. Tighten inlet valve plugs (8, Figure 6-11) to 100 ft.lbs. (136 N.m) torque.

9. Loosen plugs and retighten to 100 ft. lbs. (136N.m) torque to seat inlet valves.

FIGURE 6-19. OUTLET VALVE SEAT INSPECTION

1. Valve Seat2. Special Screw

3. Special Tool

FIGURE 6-20. OIL SEAL REMOVALFIGURE 6-21. INLET VALVE INSTALLATION

1. Inlet Valve Assembly


10. Install new outlet valve seats (1, Figure 6-22) usingJDH-39B-1 Installer and Removal Tool (2). Driveseat into housing until flange of tool is against faceof housing.

For a pump equipped with spacers (2 & 6, Figure6-23) having a flat area to prevent rotation, becertain spacer is properly aligned with flat area onpump shaft journal.

11. Put spacer (6, Figure 6-23) on splined end of shaft(8).

12. Press bearing cone (7) on splined end of shaftagainst shaft journal, making sure spacer (6) isproperly aligned.

13. Put race (4) (with VESPEL® thrust washers (5 & 1)where applicable) on pump shaft (8).

DO NOT use grease to hold needle rollers. Doingso can restrain roller movement and cause pumpfailure. Use only clean hydraulic oil.

14. Insert needle rollers between race (4) and pumpshaft journal.

15. Put spacer (2) and thrust washer (1) on unsplinedend of pump shaft, checking for proper spacer andthrust washer placement.

16. Install bearing cone (3) on end of pump shaft. Pressbearing cone against pump shaft journal.

NOTE: Taper roller bearings must be pressed ontopump shaft even if shaft has not been disassembled.This assures correct pump shaft end play.

17. Press bearing cones against pump shaft journaleven if shaft has not been disassembled.

Seal Ring Installation (Preferred Method)

18.Shaft Seal Sizer Tool (John Deere part numberJDG-493) can be used to aid sealing ring installa-tion . If this tool is not available, refer to the alter-nate method on the following page.

18A. Install JDG-494 Spline Protector Tool (2, Figure6-24) on pump shaft.

FIGURE 6-22. OUTLET VALVE SEAT INSTALLATION

1. Valve Seat 2. Special Tool

FIGURE 6-23. SHAFT ASSEMBLY

1. Thrust Washer2. Spacer3. Bearing Cone4. Bearing Race

5. Thrust Washer6. Spacer7. Bearing Cone8. Shaft (Splined End)

FIGURE 6-24. SEAL RING INSTALLATION

1. Seal Sizer Tool2. Spline Protector Tool

3. Seal Ring


19A. Carefully slide new sealing ring (3) over splineprotector and down into groove on pump shaftmaking sure sealing ring does not twist. Use op-tional JDG- 493 sizing tool (1) to aid installation.

20A. Remove JDG-494 Spline Protector.

21A. Position sealing ring in groove. Leave tool inposition approximately 5 minutes to allow sealingring to set.

Seal Ring Installation (Alternate Method)

18B. Install JDG-494 Spline Protector Tool (2, Figure6-24) on pump shaft.

19B. Carefully slide new sealing ring (3) over splineprotector and down into groove on pump shaftmaking sure sealing ring does not twist.

20B. Remove JDG-494 Spline Protector.

21B. Clamp sealing ring in groove using a hoseclamp (2, Figure 6-25). Put shim stock (1) betweenclamp and sealing ring to prevent sealing ringdamage. Leave hose clamp in place approxi-mately 5 minutes to allow sealing ring to set.

22. Remove seal sizer tool (or hose clamp) and in-spect.

23. Install pump shaft in housing using JDG-494 SplineProtector to prevent seal damage. Remove splineprotector tool.

DO NOT drive bearing cup all the way down againstbearing cone.

24. Install remaining bearing cup (20, Figure 6-11) inpump leaving a gap between the cup and bearingcone. Installation of shims and pressure compen-sator valve housing will properly align bearing cupand cone.

NOTE: If end play was out of specification, or bearingcones and cups have been replaced, DO NOT installO-rings, packings or outlet valves.

25. Install shims (28) in pressure compensator valvehousing using a small amount of petroleum jelly tohold shims in place. Install pressure compensatorvalve housing on pump.

26. Tighten cap screws alternately to 50 ft. lbs. (70N.m) torque. Continue tightening capscrews alter-nately to 85 ft. lbs. (115 N.m) torque.

27. Check shaft end play using procedure describedin ‘‘Disassembly’’ step 8. Increase number or sizeof shims in pressure compensator valve housing ifend play is greater than 0.004 in. (0.100 mm).

End Play Specification

Acceptable . . . 0.001-0.004 in. (0.025-0100 mm)

28. Remove pressure compensator valve housing frompump housing.

Outlet valve assemblies must be installed in theiroriginal bores.

FIGURE 6-25. SEAL RING INSTALLATION(ALTERNATE METHOD)

1. Shim Stock 2. Hose Clamp


29. Install outlet valves (1, Figure 6-26) in their originalbores.

NOTE: Apply a small amount of petroleum jelly toO-ring, packings and shims to hold them in placeduring assembly.

30. Install O-ring (1, Figure 6-27), packings (2, 3, and5) and shims (4).

Serious personal injury and pump componentdamage may result if the pressure compensatorvalve housing is not correctly installed to pumphousing. The high pressure passages (1, Figure6-28) must line up when pressure compensatorvalve housing is installed to pump housing. Referto Figure 6-28 for identification and location.

31. Install pressure compensator valve housing (2,Figure 6-28) to pump housing (3) making sure highpressure passages (1) and low pressure passages(4) are aligned.

32. Tighten capscrews to 50 ft. lbs. (70 N.m) torque.Continue tightening capscrews alternately to 85 ft.lbs. (115 N.m) torque.

33. Install O-rings (2, Figure 6-11) and shields (3) onpiston plugs (1).

FIGURE 6-26. OUTLET VALVE INSTALLATION

1. Outlet Valve Assembly

FIGURE 6-27. PRESSURE COMPENSATOR HOUSING SEALING COMPONENTS

1. O-Ring2. Packing3. Packing

4. Shims5. Packing

FIGURE 6-28. OIL PASSAGE ALIGNMENT

1. High Pressure Passage2. Pressure Compensator

Housing

3. Pump Housing4. Low Pressure Passage


NOTE: Original pistons must be installed into theiroriginal bores. All eight (8) springs must be of the samecolor code.

34. Install piston assemblies. For easier assembly,rotate the pump shaft until piston being installed ison the low side of the cam.

To prevent damage to shields, DO NOT use anair-operated wrench to tighten piston plugs; use atorque wrench.

35. Tighten piston plugs (1, Figure 6-11) to 135 ft. lbs.(185 N.m) torque.

Disassemble and Inspect Pressure CompensatorValve (Stroke Control Valve)

NOTE: Disassemble pressure compensator valve onlyif there is evidence of malfunction. The pressure com-pensator valve housing does not have to be removedfrom the pump. If the pressure compensator valve isremoved from the pump housing, mark both housingsbefore disassembly.

1. Install pump on a bench fixture after thoroughlycleaning outside surface of pump.

2. Loosen all plugs on pressure compensator valvehousing (Figure 6-29).

NOTE: Remove adjusting screw (20, Figure 6-30) andbushing assembly (22) prior to removing plug (1).Pressure compensator valve sleeve packings will bedamaged if adjusting screw and bushing assembly arenot removed first.

3. Remove adjusting screw (20, Figure 6-30) andbushing assembly (21, 22, & 23), special washer(24), spring (25), spring guide (26) and pressurecompensator valve (27).

4. Inspect spring (25) for wear or damage.

5. Check compression rate of spring (25) using aspring compression tester.


Free Length (Approximate) . . . . . . . . . . 3.62 in. (92 mm)Test Length at125-155 lb. (556-690 N) . . . . . 3.31 in. (84 mm)

6. Inspect spring guide (26) for wear.

7. Disassemble adjusting screw and bushing assem-bly, removing nut (19) and screw (20) from adjust-ing screw bushing (22).

8. Discard O-rings (21 and 23).

9. Remove plug (14) from housing.

10. Remove crankcase outlet valve plug (12), spring(10) and crankcase outlet valve (9) from housing.

11. Inspect spring (10) for wear or damage and checkcompression rate of spring using a spring com-pression tester.


Free Length (Approximate) . . . 3.43 in. (87 mm)Test Length at 14-17 lb.(63-77 N) . . . . . . . . 3.0 in. (74.5 mm)

12. Remove resonator plug (5) and pin (6) from hous-ing.

NOTE: Pin (6) and crankcase outlet valve (9) must slidefreely in their bores.

13. Inspect crankcase outlet valve (9) and pin (6) forwear.

New Part Specification

Crankcase Outlet Valve

OD . . . . . 0.5507-0.5515 in. (13.990-14.010 mm)Pin OD . . . 0.1246-0.1248 in. (3.165-3.170 mm)

FIGURE 6-29. PLUG REMOVAL

1. Plug


14. Discard O-rings (7 & 11) on plugs.

DO NOT use a punch to remove pressure compen-sator valve sleeve. Sleeve could be damaged andcause sticking.

15. Carefully remove pressure compensator valve (27)sleeve using a wood or brass dowel. Remove fromplug opening, pushing toward adjusting screwopening.

16. Inspect pressure compensator valve assembly.Valve (1, Figure 6-31) must move freely in bore (2).Valve face (3) and seat (4) must be free of pits,nicks, grooves. Replace valve and sleeve if drag ordamage exists.

New Part SpecificationValve OD . . . . . . . . . . . . 0.2661-0.2665 in. . . . . . . . . . . . . . . . . . (6.759-6.769 mm)

Sleeve ID (Top End) . . . . . . 0.2667-0.2673 in. . . . . . . . . . . . . . . . . (6.7740-6.7900 mm)


FIGURE 6-30. PRESSURE COMPENSATOR ASSEMBLY

1. Plug (1)2. O-Ring (1)3. Fitting (1)4. O-Ring (1)5. Plug (1)6. Pin (1)7. O-Ring (1)8. Capscrew (4)

9. Valve (1)10. Spring (1)11. O-Ring (1)12. Plug (1)13. O-Ring (2)14. Plug (2)15. Housing (1)16. Packing (2)

17. Packing (8)18. O-Ring (1)19. Nut (1)20. Adjustment Screw (1)21. O-Ring (1)22. Bushing (1)23. O-Ring (1)24. Special Washer (1)

25. Spring (1)26. Guide (1)27. Control Valve (1)28. Backup Ring (1)29. O-Ring (1)30. O-Ring (1)31. Washer (1)32. Pressure Test Q.D.(1)


17. Discard O-ring and backup ring on sleeve.

18. Remove plug (14, Figure 6-30) and quick discon-nect fitting (32) and discard O-rings.

Assemble Pressure Compensator Valve (Stroke Control Valve)

NOTE: All pressure compensator valve parts must bethoroughly cleaned. All passage holes in parts must beopen and clean.

1. Install new O-ring (29, Figure 6-30) and backupring (28) through port in pressure compensatorvalve housing.

2. Using a new O-ring (2) install plug (1) in fitting (3).

3. Install new backup ring (28) and O-ring (29) onpressure compensator valve sleeve (27).

DO NOT use a punch to install pressure compen-sator sleeve. Damage could occur to the sleeveand cause sticking.

4. Coat all O-rings with oil during installation

5. Carefully install pressure compensator valvesleeve through adjusting screw port making suresleeve seating surfaces are not damaged.

6. Install new O-ring (23) on bushing (22) and newO-ring on adjusting screw (20).

7. Install screw (20) into bushing (22).

8. Install nut (19).

9. Install pressure compensator valve into sleeve inhousing.

10. Install spring guide (26) with spring (25).

11. Install adjusting screw and bushing assembly withcopper washer (24).

12. Install new O-ring (11) on crankcase outlet valveplug (12) and resonator plug (5).

NOTE: Pin (6) and crankcase outlet valve (9) must slidefreely in their bores.

13. Carefully install crankcase outlet valve (9) intopressure compensator valve housing.

14. Install crankcase outlet valve plug (1) with spring(5) into housing.

15. Install pin (3) and resonator plug (2) into housing.

16. Put new O-rings on plug (14) and pressure testquick disconnect (32). Install into pressure com-pensator valve housing.

17. Install new O-ring (1, Figure 6-32) and packings (2,3, and 9).

18. Install shims (4).

Serious personal injury and pump componentdamage may result if pressure compensator valvehousing is not correctly installed to pump housing.The high pressure passages (5) must line up whenpressure compensator valve housing is installed topump housing. Refer to Figure 6-32 for passageidentification and location.

19. Install pressure compensator valve housing (6) topump housing (7) making sure system pressurepassages (5) and charge pressure passages (8)are aligned.

FIGURE 6-31. PRESSURE COMPENSATOR VALVEASSEMBLY

1. Valve2. Sleeve Bore

3. Valve Face4. Valve Seat


NOTE: If a new pressure compensator valve housingis used or pump shaft and/or bearings replaced, endplay must be checked. Refer to steps 7. and 8. in‘‘Disassembly’’.

20. Tighten capscrews (8, Figure 6-30) alternately to50 ft. lbs. (70 N.m) torque. Continue tighteningcapscrews alternately to 85 ft. lbs. (115 N.m)torque.

21. Tighten control valve housing plugs to specifica-tions listed in Figure 6-33.

22. Refer to ‘‘Steering Circuit Checkout Procedure’’ forpump pressure adjustment procedures.

FIGURE 6-32. OIL PASSAGE ALIGNMENT

1. O-Ring2. Packing3. Packing4. Shims5. High Pressure Passage

6. Pressure CompensatorHousing

7. Pump Housing8. Low Pressure Passage9. Packing


PUMP COMPONENT PARTS DIMENSIONS

SPRING SPECIFICATIONS

TORQUE SPECIFICATIONS

ITEM MEASUREMENT INCHES MILLIMETERSPump Shaft End Play 0.001--0.004 0.025--0.100Piston Outside Diameter 0.8740--0.8744 22.2001--22.210Piston Bore Inside Diameter 0.8749--0.8753 22.223--22.233Shaft Journal Outside Diameter 1.7442--1.7448 44.302--44.318Shaft Bearing Race Inside Diameter 2.2457--2.2465 57.041--57.061Shaft Bearing Race Outside Diameter 2.8140--2.8159 71.475--71.525Shaft Needle Rollers Outside Diameter 0.250 6.35Inlet Valve Lift 0.078--0.120 2.0--3.0Pressure Compensator Valve Spring Guide Outside Diameter 0.9289--0.9309 23.595--23.645Pressure Compensator Valve Stem Outside Diameter 0.2661--0.2665 6.759--6.769Pressure Compensator Valve Sleeve Inside Diameter 0.2667--0.2673 6.7740--6.7900Crankcase Outlet Valve Outside Diameter 0.5507--0.5515 13.990--14.010Crankcase Outlet Valve Pin Outside Diameter 0.1246--0.1248 3.165--3.170

ITEM COMPRESSION FORCE SPRING TEST LENGTH

POUNDS NEWTONS INCHES MILLIMETERSPiston Spring Free Length (Approximate) 2.44 62.0

Piston Spring (Yellow) 34--35.5 151--158 1.62 41.1

Piston Spring (Green) 35.5--37 158--165 1.62 41.1

Piston Spring (Blue) 37--38.5 165--171 1.62 41.1

Piston Spring (Red) 38.5--40 171--178 1.62 41.1

Outlet Valve Spring Free Length (Approximate) 0.48 12.2

Outlet Valve Spring 2.5--3 11--14 0.30 7.60

Pressure Compensator Valve Spring Free Length (Approximate) 3.62 92.0

Pressure Compensator Valve Spring 125--155 556--690 3.31 84.0

Crankcase Outlet Valve Spring Free Length (Approximate) 3.43 87.0

Crankcase Outlet Valve Spring 14--17 63--77 3.0 74.5

ITEM FT. LBS. N.m

Pressure Compensator Valve, Housing to Pump 85 115

Pressure Compensator Valve Resonator Plug 100 136

Pressure Compensator Valve Plug 80 108

Pressure Compensator Valve Adjusting Plug 110 150

Test Port Plug 25 34

Crankcase Outlet Valve Plug 45 61

FIGURE 6-33. PUMP SPECIFICATIONS CHARTS


NOTES


HOIST CIRCUIT OPERATION AND COMPONENT DESCRIPTION

CIRCUIT OPERATIONFlow from the shaft end cartridge of the tandem pumpenters the hoist valve inlet port. Return oil flows fromthe open center hoist valve to the hydraulic filter(s). Atthe hydraulic filter(s), oil is combined with flow from thecover end cartridge of the tandem pump and routed tothe heat exchanger to remove heat generated duringretarding or service brake application. This combinedoil supply is routed to the rear brakes for cooling andreturned to tank. A portion of this cooled oil is suppliedto the brake/steering pump.

When the body is on the frame, empty or loaded, thehoist valve spool should be in the ‘‘float’’ position. Both‘‘extend’’ and ‘‘retract’’ sides of the hoist cylinders areopen to tank, and the frame is carrying all the load.

HOIST VALVE

The hoist valve is controlled by pilot pressure from thehoist pilot control valve in the Auxiliary Manifold andorificed check valves located in the pilot pressure linesand hoist up/return line.

If the operator selects ‘‘Raise’’ to raise the dump body,pilot pressure from the Auxiliary Manifold repositionsthe spool in the hoist valve to direct oil flow through theovercenter valve to the hoist cylinder ‘‘Raise’’ ports. Aninternal relief valve (in the hoist valve) is adjusted tolimit maximum hoist pressure to 2750 psi (19.3 MPa).

The load can be held in position by placing the hoistvalve in ‘‘Hold’’ when the operator releases the hoistlever. The hoist valve will go to the ‘‘Hold’’ position whenpilot pressure is removed and the internal spring anddetent assembly repositions the spool to block oil flowto and from the hoist cylinders and tank return. Aninternal load check valve is used to hold pressure in thehoist cylinders if the operator selects the ‘‘Raise’’ posi-tion after the valve has been in the ‘‘Hold’’ position. Thecheck valve allows the pump to attain a pressure equalto or greater than the pressure in the hoist cylinders toprevent the body from dropping as the spool is shiftedfrom the ‘‘Hold’’ to ‘‘Raise’’ position.

To lower the dump body, the operator selects the‘‘Power Down’’ position which directs pilot pressure tothe opposite end of the hoist valve spool. Oil then flowsto the annulus area of the hoist cylinders to cause themto retract. Maximum ‘‘Power Down’’ pressure is limitedto 1000 psi (6.9 MPa) by the adjustment on the end ofthe valve.

After the body has started to descend, the operator canselect the ‘‘Float’’ position by releasing the hoist lever.This removes pilot pressure from the hoist valve spooland allows the internal spring and detent assembly toreposition the spool to allow oil to return from the hoistcylinders to the tank.

FIGURE 7-1. HOIST VALVE

L07006 5/94 Hoist Circuit Operation and Component Description L7-1

AUXILIARY MANIFOLD

The Auxiliary Manifold, located to the rear of the fueltank, provides several system functions. Oil flows fromthe brake/steering pump to the manifold inlet and pro-vides 2750 psi (19.0 MPa) oil pressure to the parkingbrake solenoid. When the solenoid is energized, oilflows to the parking brake actuator to release the springapplied parking brake. A switch monitoring this oilpressure illuminates a warning lamp on the instrumentpanel to indicate the parking brake is applied. A secondpressure switch monitoring pump oil pressure illumi-nates the Emergency Steering warning light and hornif pressure decreases to 1800 psi (12.4 MPa).

Oil for the hoist pilot circuit flows through a pressurereducing valve to reduce the pressure from 2750 psi(19.0 MPa) to 125 psi (862 kPa).

When the operator selects the ‘‘Raise’’ position on thehoist lever, a switch energizes the ‘‘Up’’ solenoid shift-ing the hoist pilot control valve spool to direct oil to thehoist valve and move the spool to the ‘‘Raise’’ position.When the operator selects ‘‘Power Down’’, the ‘‘Down’’solenoid is energized to direct oil to the opposite endof the hoist valve spool.

COUNTER-BALANCE VALVE

The counter-balance (overcenter) valve is located onthe final drive frame cross tube. This valve provides a‘‘cushion’’ of oil in the hoist cylinder annular area toprevent damage to the cylinders as they approachmaximum extension and the weight of the load is at therear edge of the dump body.

There are no serviceable parts in the counter-balancevalve. If the valve is defective, it must be replaced.

HOIST CYLINDERS

Two stage, double acting cylinders with sealed stagesraise and lower the body. Hoist circuit oil enters andleaves the cylinders at the extend (‘‘EXT’’) port andflows through a tube in the second stage to extend thehoist cylinder. When in ‘‘Power down’’, oil enters andleaves the cylinders at the retract (‘‘RET’’) port andflows between the hoist oil tube and inside of thesecond stage. Orifices in the first and second stagetubes direct oil to the annular area to retract the cylin-ders.

CHECK VALVES

Three orificed check valves are used in the hoist circuit.Their purpose is to restrict oil flow during body downoperation and eliminate the possibility of high oil pres-sure surges in the hydraulic system.

Two of the check valves are located in the "power up"and "power down" pilot lines in circuit between theauxiliary manifold and the hoist valve.

A third check valve is located in the hoist up / returnline which is attached to a junction block mounted tothe final drive frame cross tube.

When the operator raises the body, hydraulic oil willunseat the check valves and allow unrestricted flow ofoil to the hoist cylinders. When hoist down is selectedthe check valves in the pilot lines will close sending oilflow through a 0.040 in. (1.016 mm) orifice. The orificeswill restrict oil flow, slowing down the movement of thehoist spool valve and allowing hydraulic oil to drainslowly back to tank. The check valve in the hoist up /return line will also close during "power down". Oil willflow through a 0.375 in. (9.525 mm.) orifice. This willrestrict oil flow back to tank and allow the body to lowerat a slower rate of speed.

FIGURE 7-2. AUXILIARY MANIFOLD

L7-2 Hoist Circuit Operation and Component Description L07006 5/94

HOIST CIRCUIT COMPONENT REPAIR

HOIST VALVE

Removal

1. Be certain the engine is shut down and the keyswitch has been ‘‘Off’’ for at least 90 seconds toallow the steering accumulator to automaticallybleed down. Open the brake accumulator bleed-down valves on the Low Brake Pressure DetectionModule and bleed the pressure from the brakeaccumulators. Close the valves after pressure hasbeen released.

2. Loosen vent plugs above suction and return tubeson hydraulic tank.

3. Clean dirt accumulation from the area of the hoistvalve.

4. Remove all hoses connected to hoist valve (4,Figure 8-1). Cap all lines and valve ports to preventcontamination.

5. Remove capscrews and lockwashers (3). Removevalve from mount on fuel tank.

Installation

1. Position hoist valve (4, Figure 8-1) on tank mounts.Install mount capscrews and lockwashers (3).Tighten to standard torque.

2. Remove caps and connect all hoses using newO-rings at split flange clamp connections. Tightencapscrews to standard torque.

3. Tighten vent plugs on top of tank. Refill hydraulictank as required.

4. Refer to ‘‘Hoist Circuit Checkout’’ procedure forpower down and hoist pressure relief settings.

FIGURE 8-1. HOIST VALVE INSTALLATION

1. Fuel Tank2. Auxiliary Manifold3. Capscrews &

Lockwashers

4. Hoist Valve5. Check Valves

FIGURE 8-2. HOIST VALVE

1. Socket HeadCapscrew & Washer

2. Socket HeadCapscrew & Washer

3. ‘‘Power Down’’ PressureAdjustment

4. Hoist Circuit PressureRelief Adjustment

5. Hoist Pressure Test Port

L08006 4/92 Hoist Circuit Component Repair L8-1

Disassembly

NOTE: The valve body and spool are matched. If atdisassembly, one is found damaged, both must bereplaced.

1. Remove socket head capscrews (1, Figure 8-2).Remove cover (1, Figure 8-3), spacer (2), andO-ring (3).

2. Remove socket head capscrews and remove de-tent housing (17).

3. Hold cap (9) and unscrew detent socket (11).

4. Remove centering spring (8), spring guides (7)plate (6), and O-rings (5 & 26).

5. Pull valve spool assembly out of valve body fromspring cover end.

6. Hold spool to prevent damage to O.D. surface.Unscrew cap (1, Figure 8-4), remove spring (2)and load check valve (3).

7. Remove plug (5) and discard O-ring (4).

8. Depress cap nut (19, Figure 8-3), remove snap ring(22). When spring tension is released, eleven de-tent balls (14) will be released from between ballretainers.

9. Remove spring (16), spring retainer (25), sleeve(13) and ball retainers (12) housing (17).

10. Remove relief valve cap nut (27), jam nut, washers(29) and adjusting screw (28).

11. Remove spring (32) and poppet (33) from cap (30).

12. Remove cap (30) and pilot seat (35).

FIGURE 8-3. HOIST VALVE ASSEMBLY

1. Cover 2. Plate 3. O-Ring 4. Spool Assembly 5. O-Ring 6. Plate 7. Spring Guide 8. Spring 9. Cap10. Roll Pin

11. Detent Socket12. Ball Retainer13. Sleeve14. Ball15. Detent16. Spring17. Housing18. Jam Nut19. Cap Nut20. Washer21. Plug

22. Snap Ring23. O-Ring24. Adjusting Screw25. Spring Retainer26. O-Ring27. Cap Nut28. Adjusting Screw29. Washer30. Relief Cap31. O-Ring32. Spring

33. Poppet34. O-Ring35. Pilot Seat36. Spacer37. Spring38. Poppet39. Seat40. O-Ring41. Cap

L8-2 Hoist Circuit Component Repair L08006 4/92

13. Remove spacer (36), spring (37) and relief poppet(38).

14. Remove plug (40) and seat (39).

Assembly

1. Inspect all components, replace damaged partsas necessary. If spool or main housing is dam-aged, both must be replaced as they are amatched set.

2. Install new O-rings as valve components are as-sembled.

3. Install relief seat (39, Figure 8-3), O-ring (40) andcap (41).

4. Install relief poppet (38), spring (37), spacer (36),pilot seat (35), O-ring (31) and cap (30).

5. Install poppet (33), spring (32) and adjusting screw(28) into cap.

6. Install washers (29), jam nut and cap nut (27).

Screw adjusting screw into plug enough to justbottom on pilot pin spring. Final adjustment will bemade when valve is mounted on truck.

7. Insert load check valve (3, Figure 8-4), spring (2)and cap (1) in valve spool.

8. Install O-ring (4) and plug (5) in other end of spool.

9. Lubricate spool and carefully slide spool into valvebody.

10. Place O-ring, (5, Figure 8-3) plate (6 ), spring guide(7), and spring (8) on cap (9).

11. Support spool to prevent it from sliding out of valvebody. Install remaining spring guide (7) and detentsocket (11).

12. Compress spring and screw detent socket (11) intocap. Place one drop of medium strength Loctite®

to threads of detent socket (11) before placing intocap (9).

13. Position O-ring (26) and housing (17) over center-ing spring. Install socket head capscrews andlockwashers. Tighten to 10 ft. lbs. (13.8 N.m)torque.

14. Install ball retainer (12), balls (14), remaining ballretainer, sleeve (13), spring retainer (25) andspring (16) in housing (17).

15. Install new O-ring (23) on plug (21).

16. Insert plug in housing, compress spring and insertsnap ring (22).

17. Install power down adjustment screw (24), washers(20), jam nut (18) and cap nut (19).

18. Adjustment of power down will be made after valveis installed on truck.

19. Install O-ring (3), plate (2) and end cap (1). Installsocket head capscrews and washers. Tighten cap-screws to 10 ft. lbs. (13.8 N.m) torque.

FIGURE 8-4. HOIST VALVE SPOOL ASSEMBLY

1. Cap 2. Spring 3. Load Check Valve 4. O-Ring 5. Cap


HOIST CYLINDER

Removal

1. Be certain the engine is shut down and the keyswitch has been ‘‘Off’’ for at least 90 seconds toallow the steering accumulator to automaticallybleed down.

2. Be sure body is on frame and hoist valve spool isin ‘‘float’’ position.

3. Mark hose to cylinder port location on bottom ofcylinder.

4. Disconnect hoses and plug lines to prevent con-tamination.

5. Remove nut (2, Figure 8-5) and capscrew (1) frompin (3) on upper mount.

6. Remove capscrews (7), lockwashers (8), and re-tainer plate (6) from lower mount.

7. Attach lifting device and support hoist cylinder.

8. Remove upper mount pin (3).

9. Move cylinder out of body mount ears and slideoff lower frame mount.

Installation

1. Raise cylinder, slide cylinder onto lower mount.

2. Move cylinder between upper mount ears. Installupper pin (3, Figure 8-5).

3. Install capscrew (1) and nut (2).

4. Install retainer plate (6), lockwasher (8) and cap-screws (7). Tighten to standard torque.

5. Connect hoses to proper port on lower cylindereye.

FIGURE 8-5. HOIST CYLINDER INSTALLATION

1. Capscrew2. Nut3. Pin4. Snap Ring

5. Bearing6. Retainer Plate7. Capscrew8. Lockwasher


FIGURE 8-6. HOISTCYLINDER ASSEMBLY

1. Capscrew 2. Flatwasher 3. Bearing Retainer 4. Housing 5. Tube 6. Tube 7. Bearing 8. Buffer Seal 9. Rod Seal10. Rod Wiper11. Rod Wiper12. Rod Seal 13. Buffer Seal14. Bearing15. Backup Ring16. O-Ring17. Capscrew18. Flatwasher19. Bearing20. Seal21. Bearing


Disassembly

1. Remove capscrews (1, Figure 8-6) and flat wash-ers (2) securing bearing retainer (3) to housing (4).

2. Pull housing (4) from tube (5) and rod eye tube (6).

3. Remove capscrews (17), flat washers (18) and rodbearing retainer (22) from tube (6).

4. Pull tube (5) and bearing retainer (3) from rod (6).

5. Remove all seals, bearings, O-rings and wipers.


NOTE: Use only clean solvent, lint free wiping cloth,and dry, filtered compressed air when cleaning andhandling hydraulic cylinders. Immediately after clean-ing and inspection, coat all surfaces with clean TypeC-4 hydraulic oil.

1. Remove and discard all seals and O-rings.

2. Thoroughly clean and dry all parts.

3. Visually inspect parts for damage or excessivewear.

4. If cylinder bores and plated surfaces are exces-sively worn or grooved, the cylinder parts must bereplaced or replated and machined to originalspecifications. For assistance on wear limits andspecifications, contact your Haulpak® Distributor.

Assembly

1. Install bearing (14, Figure 8-6), buffer seal (13), rodseal (12) and wiper (11) in bearing retainer (3). Lipof buffer seal and rod seal point toward bearing.Lip of wiper points away from bearing.

2. Install O-ring (16) and backup ring (15) on retainerwith backup ring toward bolt flange.

3. Install bearing (7), buffer seal (8), rod seal (9) andwiper (10) in tube (5). Lip of buffer seal and rodseal point toward bearing. Lip of wiper pointsaway from bearing.

4. Lightly coat all seals and bearings with hydraulicoil.

5. Position bearing retainer (3) on tube (5). Slide tubeonto rod eye tube (6).

6. Install bearings (19) and seal (20) on bearingretainer (22).

7. Install bearing retainer (22) into tube (5) and overend of rod (6).

8. Install capscrews (17) and flat washers (18).Tighten to standard torque.

9. Install bearings (21) on tube (5). Slide housing overtube. Install gland (3), capscrews (1)and washers(2) to housing (3). Tighten to standard torque.

10. If test equipment is available for testing after as-sembly, the following values should be present:

Extended at 2500 psi (17 238 kPa), leakage at‘‘RET’’ port should not exceed 20 cu. in. (32 l) perminute.

Retracted at 2500 psi (17 238 kPa), leakage at‘‘EXT’’ port should not exceed 40 cu. in. (0.64 l)per minute.

11. Plug ports at rod eye to prevent contaminationduring handling of cylinder.

Hoist Cylinder Mounting Bearing Replacement

The following procedure is applicable to either end ofcylinder:

1. Remove one snap ring (4, Figure 8-5) retainingbearing (5).

2. Remove bearing.

3. Repeat Steps 1 and 2 for other bearing.

4. Inspect bearing bores, pin and lower frame mountfor damage.

5. Press spherical bearing (5) into bore of cylindereye.

6. Install snap ring (4).

7. Repeat Steps 5 and 6 for other end.


HYDRAULIC CHECK-OUT PROCEDURE

GENERAL INFORMATIONThe hydraulic check-out procedure is intended to helpthe technician to check, adjust, and diagnose prob-lems in the steering and hoist circuits. The technicianshould read the entire check-out procedure prior toperforming any steps to become familiar with the pro-cedures and all the warnings and cautions.

The check-out procedure begins by checking the basicsystem before checking individual components.

Included on the last page is a data sheet to record theinformation observed during the hydraulic systemcheck-out procedure. The data sheet is designed to beremoved, copied, and used during the check-out pro-cedure.

* Steps indicated in this manner should be re-corded on the data sheet for reference.

STEERING CIRCUIT CHECK-OUT &ADJUSTMENT PROCEDUREThe steering circuit hydraulic pressure is supplied fromthe piston pump and steering accumulator. Somesteering system problems, such as spongy or slowsteering or abnormal operation of the "Low SteeringPressure" warning light can sometimes be traced tointernal leakage of steering components. If internalleakage is suspected, refer to "Steering Circuit Compo-nent Leakage Test."

NOTE: Excessive internal leakage within the brakecircuit may contribute to problems within the steeringcircuit. Be certain that brake circuit leakage is notexcessive before troubleshooting steering circuit. ForBrake Circuit Test Procedure, refer to Section "J",Brake System.

The steering circuit can be isolated from the brakecircuit by removing the brake supply line from thedistribution manifold to the brake accumulators(see WARNING). Plug the brake supply lines andcap the ports in the distribution manifold to preventhigh pressure leakage.

Hydraulic fluid escaping under pressure can havesufficient force to enter a person’s body by pene-trating the skin and cause serious injury, and pos-sibly death, if proper medical treatment by aphysician familiar with this type of injury is notreceived immediately.

Before disconnecting pressure lines, replacingcomponents in the hydraulic circuits, or installingtest gauges, ALWAYS bleed down hydraulic steer-ing accumulator.

The steering accumulator can be bled down with en-gine shut down, turning key switch "Off", and waiting90 seconds. Confirm the steering pressure is releasedby turning the steering wheel - No front wheel move-ment should occur.

INITIAL SYSTEM SET-UP

Accumulator And Piston Pump Checks

The following equipment will be necessary to properlycheck-out the hydraulic steering circuit


b. Two 0-5000 psi (0-35 000 kPa) range calibratedpressure gauges and hoses.

c. Accumulator charging kit with gauges and drynitrogen

d. One oz / ml graduated container.

NOTE: The following procedures may be easier if thegauges are connected such that they can be read inthe cab or where the technician can communicate withperson operating the controls.

Prior to checking the steering system, the hydraulicsteering and brake systems must have the correctaccumulator precharge and be up to normal operatingtemperatures. Also prior to checking the system makesure the parking brake is properly adjusted. Refer toParking Brake Adjustment, Section "J". With the brakesystem functioning properly and the parking brake on,proceed as follows:

L10001 4/92 Hydraulic Check-out Procedure L10-1

NOTE: Always allow nitrogen gas temperature to ap-proach ambient temperatures before completing pre-charge procedure. For best results, chargeaccumulator in the ambient temperature conditions inwhich the truck will be operating

1. Shut down engine and turn key switch off. Wait 90seconds for the steering accumulator to com-pletely bleed down before opening circuits to takemeasurements, to make repairs, or to install orremove a gauge.

Be sure steering accumulator oil pressure hasbeen bled down. Turn the steering wheel; thewheels should not move if all oil pressure has beenrelieved.

2. Check hydraulic oil level in tank, add if required.

3. Check nitrogen charge pressure in steering accu-mulator before proceding. (Follow the accumula-tor nitrogen service procedure in this Section.)


4. Install a reliable 5000 psi (35 000 kPa) minimumpressure gauge at the pressure tap (2, Figure10-1) on the brake manifold.

5. Install a reliable 5000 psi (35 000 kPa) minimumpressure gauge at the pressure tap (1, Figure10-2) on the piston pump.

6. Start engine and cycle the oil through the circuitsto bring the the oil temperature up to normaloperating temperature. Steer slowly both left andright several times to stabilize the steering circuittemperatures (both nitrogen and oil).

7. The pressure gauge on the piston pump shouldindicate 2750 ± 50 psi (18 961 ± 345 kPa) at 1500rpm.


8. If pressure is not correct, adjust as follows:

a. Shut down engine and turn key switch off. Wait90 seconds for the steering accumulator tocompletely bleed down before opening circuitsto take measurements, to make repairs, or toinstall or remove a gauge

b. Loosen jam nut, turn adjusting screw (3) clock-wise to increase pressure or counterclockwiseto decrease pressure. Tighten jam nut.

c. Continue checking and adjusting until correctpressure is obtained.

NOTE: If the piston pump pressure or volume is low,check charge pressure at port (2). Pressure should begreater than 10 psi (69 kPa) at high idle.

9. Shut down engine and turn key switch off. Wait 90seconds, then observe the brake manifold pres-sure gauge. It should indicate zero pressure.

10. Start the engine. Immediately after starting, checkbrake manifold pressure gauge. It will quicklybuild to nitrogen pressure of approximately 1050psi (7240 kPa), pause momentarily, and then in-crease to the adjusted steering pressure of 2750± 50 psi ( 18 961 ± 345 kPa).


FIGURE 10-1 BRAKE MANIFOLD1. Brake Manifold 2. Pressure tap

FIGURE 10-2 PISTON PUMP1. High Pressure Tap 3. Adjusting Screw2. Charge Pressure 4. Allen Wrench

L10-2 Hydraulic Check-out Procedure L10001 4/92

11. Shut down engine and turn key switch off. Wait 90seconds for steering accumulator to bleed down.

12. Remove pressure gauge from piston pump.

Steering Valve Leakage Check

Never shut off keyswitch to activate accumulatorbleeddown or turn the steering wheel when steer-ing return lines or ports are open. Return port willsee accumulator oil flow during the bleed downcycle or turning of the steering wheel.

13. Disconnect steering valve return hose at steeringvalve and cap hose.

14. Install a hose into return port of steering valve andplace other end into a suitable measuring con-tainer.

15. Start engine and allow steering pressure to stabi-lize.

Never shut off keyswitch to activate accumulatorbleeddown or turn the steering wheel when steer-ing return lines or ports are open. Return port willsee accumulator oil flow during the bleed downcycle or turning of the steering wheel.

16. Shut down engine, leave key switch in the runposition.

17. Record the system volume loss from the steeringvalve. Maximum leakage should not exceed111oz / 10 min (3.3 l / 10 min).


18. If leakage is within specifications, go to step 20.If leakage is excessive, go to step 19.

19. If excessive leakage from the control valve isfound:

a. Connect return hose back to the steering valve.

b. Turn key switch off and wait 90 seconds forsteering accumulator to bleed down.

c. Inspect steering linkage for binding. This maycause the steering control valve to be held inan open position. If this occurs, the allowableleakage will be greatly affected.

d. Start engine and turn steering wheel to allowvalve to recenter itself again.

e. Shut down engine and turn key switch off, wait90 seconds for steering accumulator to bleeddown.

f. Check leakage rate again, starting at Step 13. Ifleakage is still excessive, rebuild unit accordingto the instructions in this Section.

20. Connect return hose to steering control valve.

21. Turn key switch off to bleed down accumulator.

Steering Cylinder Leakage Check

22. Start engine and turn steering wheel to full left lock.

23. Shut down engine and turn key switch off, wait 90seconds for steering accumulator to bleed down.

24. Remove hose on left steering cylinder on the endnear the frame attachment point. Plug hose endto prevent high pressure leakage.

25. Start engine and hold pressure on steering wheelagainst left lock to pressurize the end of the steer-ing cylinder still connected to the truck.

26. Measure cylinder leakage at the open steeringcylinder port while holding steering wheel againstleft lock.

27. Maximum cylinder leakage must not exceed 0.6oz / min (17.7 ml / min).

* Record leakage on data sheet.

28. Shut down engine and turn key switch off, wait 90seconds for steering accumulator to bleed down.Reconnect hose to steering cylinder.

29. Repeat procedure for the right steering cylinderwhile holding pressure on the steering wheelagainst the right lock.


30. If the steering cylinders have excessive leakage,they must be repaired or replaced.

31. Check hydraulic oil level in tank, add if required.


TROUBLESHOOTING CHART


TROUBLE: Slow Steering, Hard Steering or Loss of Power Assist

Overloaded Steering Axle.

Piston pump pressure lower than specified.

Worn or malfunctioning pump.

Restricted inlet screens in piston pump or steeringvalve.

Reduce Axle Loading.

Adjust pump pressure. See "Steering Circuit Check-Out Procedure".

Replace pump.

Clean or replace screens.

TROUBLE: Drift - Truck Veers Slowly In One Direction.

Rod end of cylinder slowly extends without turning thesteering wheel.

Worn or damaged steering linkage.

A small rate of extension may be normal on a closedcenter system.

Replace linkage and check alignment or toe-in of thefront wheels.

TROUBLE: Wander - Truck Will Not Stay In Straight Line.

Air in system due to low oil level, pump cavitation,leaking fittings, pinched hoses, etc.

Loose cylinder piston.

Broken centering springs (Steering Valve).

Worn mechanical linkage.

Bent linkage or cylinder rod.

Severe wear in steering control valve.

Correct oil supply problem and/or oil leakage.

Repair or replace defective components.

Replace centering springs.

Repair or replace.

Repair or replace defective components.

Repair steering control valve

TROUBLE: Slip - A Slow Movement of Steering Wheel Fails To Cause Any Movement of the Steered Wheels

Leakage of cylinder piston seals.

Worn steering control valve.

Replace seals.

Repair or replace steering control valve.

TROUBLE: Spongy or Soft Steering

Low oil level.

Air in hydraulic system. Most likely air trapped in cylin-ders or lines.

Service hydraulic tank and check for leakage.

Bleed air from system. Placing ports on top of cylinderwill help avoid trapping air.

TROUBLE: Erratic Steering

Air in system due to low oil level, cavitating pump, leakyfittings, pinched hose, etc.

Loose piston in steering cylinder.

Correct condition and add oil as necessary.

Repair or replace cylinder.


TROUBLESHOOTING CHART (Continued)


TROUBLE: Free Wheeling - Steering Wheel Turns Freely with No Back Pressure or No Action of the FrontWheels

Lower splines of column may be disengaged or dam-aged.

No flow to steering control valve can be caused by:

1. Low oil level.

2. Ruptured hose.

3. Broken gerotor drive pin.

Repair or replace steering column.

1. Add oil and check for leakage.

2. Replace hose.

3. Replace drive pin.

TROUBLE: Excessive Free Play at Steered Wheels

Broken or worn linkage between cylinder and steeredwheels.

Leaky cylinder seals.

Check for loose fitting bearings at anchor points insteering linkage between cylinder and steered wheels.

Remove and replace cylinder seals.

TROUBLE: Binding or Poor Centering of Steered Wheels

Binding or misalignment in steering column or splinedcolumn or splined input connection.

High back pressure in tank can cause slow return tocenter. Should not exceed 300 psi (2068 kPa).

Large particles can cause binding between the spooland sleeve in the steering control valve.

Align column pilot and spline to steering control unit.

Reduce restriction in the lines or circuit by removingobstruction or pinched lines, etc.

Clean the steering control valve and filter the oil. Ifanother component has malfunctioned generatingcontaminating materials, flush the entire hydraulic sys-tem.

TROUBLE: Steering Control Valve Locks Up

Large particles in meter section.

Insufficient hydraulic power (units over 15 inch).

Severe wear and/or broken pin.

Clean the steering control valve.

Check hydraulic power supply.

Replace the steering control valve.

TROUBLE: Steering Wheel Oscillates or Turns By Itself

Lines connected to wrong ports.

Parts assembled wrong. Steering control valve improp-erly timed.

Check line routing and connections.

Reassemble correctly and retime control valve.

TROUBLE: Steered Wheels Turn in Opposite Direction When Operator Turns Steering Wheel

Lines connected to wrong cylinder ports. Check proper line connections.


HOIST CIRCUIT CHECKOUT &ADJUSTMENT PROCEDURE

The following equipment will be necessary to properlycheck the hydraulic hoist circuit.


b. One 0-500 psi (0-3448 kPa) range calibratedpressure gauge and hose.

c. One 0-5000 psi (0-35 000 kPa) range calibratedpressure gauge and hose.

d. One oz / ml graduated container.

NOTE: The following procedures may be easier if thegauges are connected such that they can be read inthe cab or where the technician can communicate withperson operating the controls.

Auxiliary Valve

Pressure Check

1. Install 0-500 psi (0- 3448 kPa) pressure gauge topressure tap on auxiliary valve (Figure 10-3).

2. Start engine and operate at low idle.

3. Check hoist valve pilot pressure in " float, powerdown, power up and hold" positions. Pressureshould be 125 psi (862 kPa).


4. To adjust pilot pressure reducing valve, loosen jamnut on pressure regulator screw and turn adjust-ing screw clockwise to increase pressure or coun-terclockwise to decrease pressure. Tighten jamnut.


6. Remove pressure gauge.

Leakage Check

Excessive leakage in the auxiliary manifold can affectthe operation of the hoist circuit, park brake circuit, andother circuits connected to the manifold.

1. Disconnect piston pump vent hose at auxiliarymanifold port and cap port at valve to preventleakage.

NOTE: Before disconnecting any lines from the suc-tion line, remove center plug on top of hydraulic tankto prevent siphoning of the hydraulic oil from thehydraulic tank. Any time the siphon is broken and oilis drained from the suction line, the hydraulic tank topcover must be removed and the suction line filled withclean oil. Also loosen the capscrews at the pump inletline to remove trapped air in the line. This preventsaeration and possible pump damage during start up.

2. Disconnect auxiliary manifold drain line at hoistpump suction line and place end in a containersuitable for measuring oil volume.

3. Connect the piston pump vent hose to the hoistpump suction line in place of the auxiliary manifolddrain line.

4. Start engine and operate at low idle.

5. Measure leakage from open auxiliary manifolddrain line. Maximum leakage is 3.2 oz / min (95ml/min).



7. If leakage is within specifications, go to step 11.If leakage is excessive, go to step 8.

8. Excessive leakage can be caused by the following:

a. Defective park brake solenoid valve.

b. Defective raise/lower solenoid valve.

c. Defective pressure reducing valve.

d. Defective O-rings.

e. Defective auxiliary valve housing.

9. Remove each component and inspect for dam-age, imperfections or defective O-rings. Repair orreplace as necessary.

10. Check for excessive leakage again by starting atstep 5.

11. Connect hoses to original locations.

FIGURE 10-3 AUXILIARY MANIFOLD


Checking and Adjusting Hoist SystemPressure Relief Valve

1. Install 0-5000 psi (0-35 000 kPa) pressure gaugeto pressure tap (5, Figure 10-4) on hoist valve.

FIGURE 10-4 HOIST VALVE

1. Capscrew & Washer 4. Hoist Circuit Pressure2. Capscrew & Washer Relief Valve Adjustment3. Power Down Pressure 5. Hoist Pressure Test Port Adjustment

NOTE : If hoist valve assembly or relief valve cartridgehas been replaced or rebuilt, remove relief valve acornnut, loosen jam nut and back out adjustment screw.

Before raising body to full up position be sure there isadequate clearance between body and any overheadstructures or electric power lines.

2. Start engine and allow accumulators to charge.Raise dump body to full up position. Hold hoistcontrol valve lever in power "UP" position andadjust engine speed to 1500 RPM.

NOTE: Do not hold in power up position any longerthan necessary to obtain an accurate reading. Overheating of hydraulic oil may result.

3. Pressure gauge should indicate 2750 ± 50 psi (18961 ± 345 kPa).


4. If pressure is within specifications, go to step 7.If pressure is not within specifications, go to step5.

5. Remove acorn nut (4) and loosen jam nut. Turnrelief valve adjusting screw clockwise to increasepressure or counterclockwise to decrease pres-sure.

NOTE: Turning adjusting screw 1/16 of a turn willchange pressure approximately 100 psi (690 kPa).

6. Hold adjusting screw and tighten jam nut. Checkpressure again. Install acorn nut after correctpressure is obtained.

7. Lower dump body completely.


9. Remove pressure gauge from hoist valve.

Checking and Adjusting "Power Down"Pressure

After completing hoist relief valve setting, it is neces-sary to adjust power "Down" pressure. This adjustmentis required to provide proper hoist circuit operation.

1. Install 0-5000 psi (0-35 000 kPa) pressure gaugeto test port (5, Figure 10-4) on hoist valve.

2. Start engine and charge accumulator. Move hoistcontrol lever to power "Down" position and holdlever in this position. Increase engine RPM to highidle.

NOTE: Do not hold in power down position any longerthan necessary to obtain an accurate reading. Overheating of hydraulic oil may result.

3. Pressure gauge should indicate 1000 ± 50 psi ( 690 ± 345 kPa).


4. Return engine to low idle and release hoist controlvalve lever.


6. If pressure is within specifications, remove pres-sure gauge and stop here. If pressure is not withinspecifications, go to step 7.

7. Remove acorn nut (3) and loosen jam nut. Turnadjusting screw in to increase pressure or out todecrease pressure. Tighten jam nut.

8. Repeat steps 2 thru 6 until correct pressure isobtained. Install acorn nut (3).


TROUBLESHOOTING CHART FOR HOIST CIRCUITPOSSIBLE CAUSES SUGGESTED CORRECTIVE ACTION

TROUBLE: Pump Not Delivering Oil

Low oil level.

Siphon plugs on hydraulic tank leaking or missing.

Tank vent breathers restricted.

Pump not priming. Air leak in suction line.

PTO drive inoperable.

Pump shaft broken.

Vane(s) stuck in the rotor slot(s).

Driven in the wrong direction of rotation.

Fill to proper level.

Tighten or install plugs.

Replace filters.

Tighten clamp connections.

Check minimum engine low idle speed. Adjust idle speed, if necessary.

Inspect PTO drive assembly. Refer to Section ‘‘F’’.

Remove pump and inspect.

Check pump for free rotation.

Disassemble the pump. Check for dirt or metal chips.Clean the parts thoroughly and replace any damagedpieces. If necessary, flush the system and refill it withclean hydraulic oil. Repair as required.

Pump cartridge installed incorrectly. Disassemblepump and check cartridge for proper installation ac-cording to drive shaft rotation.

TROUBLE: Slow Hydraulic Functions

Low oil level.

Cold oil.

Air leak in suction line. (Foamy oil in tank.)

Incorrect oil viscosity.

Slow engine speed.

Low pilot oil pressure.


Warm oil to normal operating temperature.

Tighten clamp connections. Check pump shaft seal forair leak. Replace seal if necessary.

Completely drain hydraulic system. Refill with filteredoil of proper viscosity.

Increase engine speed. Check high Idle speed, adjustif necessary.

Check or adjust pilot pressure. (See auxiliary valveadjustment).


TROUBLESHOOTING CHART (Continued)POSSIBLE CAUSES SUGGESTED CORRECTIVE ACTION

TROUBLE: Slow Hydraulic Functions (Continued)

Check valves in pilot lines and/or hoist-up/return linessticking or not installed with correct direction of freeflow.

Hoist valve spool binding.

Defective hoist relief valve.

Excess leakage past cylinder seals.

Low pump output.

Remove check valves and clean. Be certain valves areinstalled with correct direction of free flow.

Inspect spool for free movement.

Refer to ‘‘Checking and Adjusting Hoist System Pres-sure Relief Valve’’, this section. Remove and inspect relief valve. Repair or replace.

Repair cylinder.

Refer to ‘‘Checking and Adjusting Hoist System Pres-sure Relief Valve’’, this section. If pressure does notreach 2,750 PSI and oil is not being bypassed at therelief valve, remove and repair pump.

TROUBLE: Low Lifting Capacity Of Hoist Circuit

Low oil level.

Excessive load .

Low pilot oil pressure.

Defective hoist relief valve.

Low pump output.

Excessive leakage around hoist spool valve.

Hoist-up/return check valve stuck, orifice restricted orinstalled backwards.

Pilot line check valves stuck, orifice restricted or in-stalled backwards.


Remove excessive load.

Refer to ‘‘Hoist Circuit Checkout And Adjustment Pro-cedure’’.

Refer to ‘‘Checking and Adjusting Hoist System Pres-sure Relief Valve’’, this section. Remove and inspectrelief valve. Repair or replace.

Refer to ‘‘Checking and Adjusting Hoist System Pres-sure Relief Valve’’, this section. If pressure does notreach 2,500 PSI and oil is not being bypassed at therelief valve, remove and repair pump.

Inspect hoist valve. Repair or replace.

Remove check valve and clean. Inspect for 0.375 in.(9.53 mm) orifice. Replace if necessary. Install checkvalve with correct direction of free oil flow.

Remove check valves and clean. Inspect for 0.040 in.(1.016 mm) orifice. Replace if necessary. Install checkvalves with correct direction of free oil flow.


TROUBLESHOOTING CHART (Continued)POSSIBLE CAUSES SUGGESTED CORRECTIVE ACTION

TROUBLE: Pump Making Noise

Low oil level.

Wrong viscosity oil.

Suction line restricted.

Suction line air leak.

Pump drive speed too slow or too fast.

Broken vanes or vane ring.


Fill with proper oil.

Check all strainers and filters for dirt and sludge. Cleanif necessary.

Inspect inlet hose and fittings.

Check and adjust engine RPM.

Remove and rebuild/replace pump.

TROUBLE: Hot Oil

Low oil level.

High pressure leak in steering circuit.

Partial restriction in hoist valve.

Restricted heat exchanger.

Improper gear range during retarding.

Worn pump.

Hoist-up/return check valve orifice restricted.

Pilot line check valves installed incorrectly for free flowor orifice restricted preventing free flow of hydraulic oilback to tank


Refer to ‘‘Steering Circuit Test Procedure’’.

Check pilot pressure.Defective relief valve or O-rings in relief valve.

Remove and clean.

Select proper gear range.

Remove pump and repair.

Remove check valve and clean. Inspect for 0.375 in.(9.53 mm) orifice. Replace if necessary.

Remove check valves and clean. Inspect for 0.040 in.(1.016 mm) orifice. Replace if necessary. Install checkvalves with correct direction of free oil flow.


HAULPAK® CHECK-OUT PROCEDURESTEERING SYSTEM DATA SHEET


STEERING SYSTEM

Operate Hydraulic Steering System to obtain proper operating temperature. Refer toCheck-out Procedures.

STEP 3 Steering Accumulator charged to 1050 psi (7240 kPa).

STEP 7 Steering Pressure At Piston Pump.

STEP 10 Steering Pressure At Brake Manifold.

STEP 17 Steering Valve Leakage.

STEP 17 Steering Valve Leakage (Second Test If Needed).

STEP 27 Steering Cylinder Leakage (Left Cylinder).

STEP 28 Steering Cylinder Leakage (Right Cylinder).

Name of Technician or Inspector Performing Check-Out

DATE


HAULPAK® CHECK-OUT PROCEDUREHOIST SYSTEM DATA SHEET


HOIST SYSTEM

Operate Hydraulic Steering System to obtain proper operating temperature. Refer toCheck-out Procedures.

Auxiliary Valve

STEP 3 Auxiliary Valve Pilot Pressure.

STEP 5 Auxiliary Valve Leakage.

Hoist Valve

STEP 3 High Pressure Relief Valve.

Power Down Pressure.

STEP 3 Power Down Pressure.

Name of Technician or Inspector Performing Check-Out

DATE


HYDRAULIC SYSTEM FLUSHING PROCEDUREThe following instructions outline the procedure forflushing the hydraulic system.

1. Shut down engine and turn key switch "Off". Allowat least 90 seconds for the steering accumulatorto bleed down. Open the brake accumulator bleeddown valves on the low brake pressure detectionmanifold. This will return all contaminants in thebrake accumulators to the hydraulic tank.

2. Thoroughly clean the exterior of the tank. Drain thehydraulic tank and remove top cover. Flush theinterior of hydraulic tank with a cleaning solvent.Inspect all hydraulic hoses for deterioration ordamage.

NOTE: If a system component fails, all flexible hosesshould be removed and back flushed with a cleaningsolvent. Inspect for small particles which may betrapped inside the hose.

3. Change high pressure filter elements.

4. Clean or replace the inline hydraulic screens at theinlet to the brake/steering pump and steeringvalve.

NOTE: The final filter in the filling apparatus must be 3micron.

NOTE: Refer to the lubrication chart in Section "P",Lubrication And Service, for proper oil selection.

5. Fill the hydraulic tank with clean filtered hydraulicoil.

6. Fill the center tube in the hydraulic tank with oil toprevent aeration of hydraulic oil during start up.Replace top cover.

7. Set all controls in the "Neutral" position. Do notsteer the truck or operate controls until the nextstep is completed.

8. Start the engine and run at 1000 RPM for fourminutes. This will circulate oil with all valves in theneutral position.

9. To increase flow and turbulence in the system,increase engine speed to full throttle and maintainfor four minutes. This will carry contaminates tothe hydraulic tank.

10. Shut down engine and turn key switch "Off". Allowat least 90 seconds for the accumulator to bleeddown. Open the brake accumulator bleed downvalves on the low brake pressure detection mani-fold. This will return all contaminants in the brakeaccumulators to the hydraulic tank.

11. Close brake accumulator bleedown valves.

NOTE: Hydraulic tank oil temperature should be 110o-130oF (43o-54oC) after accomplishing Step 12. If not,repeat Step 10 to increase oil temperature to theproper operating range.

12. Start engine and run at 1000 RPM while performingthe following:

a. Steer truck full left then full right - repeat fourtimes.

b. Steer full left (keeping pressure against thesteering wheel) and hold for 10 seconds.

c. Steer full right (keeping pressure against thesteering wheel) and hold for 10 seconds.

13. Increase engine speed to full throttle and steer fullleft and full right.

14. Return all controls to "Neutral".

15. Reduce engine speed to 1000 RPM and performthe following:

a. Extend hoist cylinders fully and "FLOAT" down- repeat four times.

NOTE: As second stage starts out of hoist cylinder inthe Power Up mode, slowly decrease engine speed toprevent sudden bottoming of the second stage.

b. Extend hoist cylinders and hold at full extensionfor 10 seconds. Hoist control lever must be heldin the "Up" position.

c. Lower hoist cylinders and hold lever in "Down"position for 10 seconds after cylinders are fullyretracted.


16. Increase engine speed to full throttle and performthe following:

a. Hoist up to full extension (see NOTE above),then allow cylinders to float down.

b. Return hoist control to "Neutral".

17. Shut down engine and turn key switch "Off". Allowat least 90 seconds for the accumulator to bleeddown.

18. Remove hydraulic filters, clean housings and in-stall new filters.

19. With hydraulic system charged, inspect all con-nections and fittings for leaks. Tighten or repairany leaking connections.


SECTION M

OPTIONS AND SPECIAL TOOLS

INDEX

LINCOLN AUTOMATIC LUBRICATION SYSTEM (M03001) . . . . . . . . . . . . . . . . . M3-1

QUICK FUEL SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M5WIGGINS QUICK FUEL SYSTEM (M05002) . . . . . . . . . . . . . . . . . . . . . . M5-1BUCKEYE QUICK FUEL SYSTEM (M05003) . . . . . . . . . . . . . . . . . . . . . . M5-1

KIM ‘‘HOTSTART’’ SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M7-1

SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M8-1

AIR CONDITIONING SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-1

PRINCIPLES OF REFRIGERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-2AIR CONDITIONER SYSTEM COMPONENTS . . . . . . . . . . . . . . . . . . . . . M9-3ELECTRICAL CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-5SYSTEM SERVICING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-6

Installing Manifold Gauge Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-9System Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-10Adding R-12 (Prior to performance test) . . . . . . . . . . . . . . . . . . . . . . M9-11System Performance Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-12Discharging System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-13Flushing Air Conditioner Components . . . . . . . . . . . . . . . . . . . . . . . M9-14

SYSTEM REPAIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-15Hoses, Fittings, and Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-15Expansion Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-15Receiver Drier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-15Thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-15Clutch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-16Compressor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-16

CHECKING COMPRESSOR OIL LEVEL . . . . . . . . . . . . . . . . . . . . . . . . M9-16EVACUATING THE SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-19CHARGING THE SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-20

TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-22Preparing For Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-22

TROUBLESHOOTING CHART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M9-23

AUTOMATIC POSITIVE LOCKING DIFFERENTIAL . . . . . . . . . . . . . . . . . . . . M12-1

RADIATOR SHUTTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M19-1

M01009 7/91 Index M1-1

NOTES

M1-2 Index M01009 7/91

LINCOLN AUTOMATIC LUBRICATION SYSTEMOperation

The automatic lubrication system (Figure 3-1) is con-trolled by an electric timer and an electrically operatedsolenoid valve. During truck operation, the timer peri-odically operates a switch which energizes the sole-noid air valve. As the solenoid air valve opens,regulated air enters the pump air motor, and the pumpbegins to operate, delivering lubricant through thesupply lines to each injector. At the same time, asregulated air is applied to the air motor, regulated air isapplied to the vent valve which keeps the vent valveclosed until the 3-way solenoid air valve is denergized.

After the injectors have cycled, lubricant pressure risesquickly to 2500 psi (17.5 MPa), and the pump stallsagainst this pressure. The pump will remain stalled fora few seconds until the timer switch contact is brokenand the solenoid air valve is de-energized, shutting offthe air supply. Trapped air exhausts, the vent valveopens, and lubricant pressure in the supply line isvented back to the reservoir. The injectors reload andthe system is reset and ready for the next lube cycle.

Figure 3-1 shows input air supply to the pump goingthrough the solenoid air valve, then through an airregulator to the air powered pump. A branch line ofregulated air is routed directly to the vent valve.

Components

The system is comprised of seven basic elements plusthe necessary hoses and lube lines:

1. Air Pressure 2. Air Regulator and Gauge 3. 24 VDC Solid State Timer 4. 3-way Solenoid Air Valve 5. Lube Injectors 6. Grease Reservoir7. Air Pump Motor

Description of Components

1. Air Powered Reciprocating Pump

a. 50:1 Pressure Ratio.

b. Reservoir Grease Capacity of 60 lbs. (27.2 kg).

2. Air Regulator and Gauge

a. Normal Operation - regulator output should beset at 60-65 psi (414-448 kPa).

b. Extreme Winter Conditions - regulator outputmay be reset to 90 psi (621 kPa).

3. 24 VDC Solid State Timer:Operating Temperature Range -20°F to 131°F (-29°C to 55°C). The timer is mounted in the cabto help insure temperature stability.

FIGURE 3-1. TYPICAL AUTOMATIC LUBRICATION SYSTEM1. Air Supply 5. Vent Valve 9. To Next Injector Grp. 13. Pipe Plug2. D.C. Timer 6. Unloader 10. Injectors 14. Pipe Plug or3. Solenoid Air Valve 7. Pump 11. Lubricant Reservoir Grease Coupler4. Air Regulator & Guage 8. To Lube Point 12. Lubricant Supply Line

M03001 12/98 Lincoln Automatic Lube System M3-1

4. Solenoid Air Valve - Three-way

a. Routes system air to the appropriate locationsin the lube system.

b. Power requirement for solenoid air valve andtimer is 15 watts.

5. Injectors (SL-1)

a. Each lube injector services only one greasepoint.

b. Injectors are available in banks of two, three,four and five as well as single replacementunits.

c. Injector output is adjustable: Maximum output = 0.08 in3 (1.31 cc). Minimum output = 0.008 in3 (0.13 cc).

d. In case of air pump malfunction, each injectoris equipped with a covered grease fitting toallow the use of external lubricating equipment.

GENERAL INSTRUCTIONS

Lubricant Required for System

Refer to ‘‘Lubrication Chart’’, Lube Key E, for correctlubricant specification and for specific lube points fora specific truck model.

1. Above 90°F (32°C) - Use NLGI No.2 multipurposegrease (MPG).

2. -25° to 90°F (-32° to 32°C) - Use NGLI No. 1 MPG.

3. Below -25°F (-32°C) - Refer to local supplier forextreme cold weather lubricant requirements.

Initial Reservoir Fill

1. Remove 0.50 in. (1.27 cm) pipe plug (13, Figure3-1) from upper portion of lubricant reservoir. Thiswill prevent damage to reservoir by allowing air toescape as reservoir is being filled.

NOTE: The 830E is factory equipped with a fill lineattached to a plate, mounted on the right side of thefront bumper and connected to grease coupler (14) onlower portion of reservoir.

2. Clean grease coupler (14) on lower portion ofreservoir.

3. Attach supply hose from external fill source tocoupler (14).

4. Fill reservoir with approximately 60 lbs. (27.24 kg)of grease. When reservoir is filled, grease willappear at upper pipe plug hole (13).

5. Remove supply hose from grease coupler (14).Remove excess grease from coupler. Install pipeplug (13) and tighten to standard torque.

System Priming

The system must be full of grease and free of airpockets to function properly. After maintenance, if theprimary or secondary lubrication lines were replaced,it will be necessary to reprime the system to eject allentrapped air. To run the air pump when priming thelube system, connect a jumper wire between the igni-tion and solenoid posts on the solid state timer.

FIGURE 3-2. REAR LUBE INJECTOR INSTALLATION (TYPICAL)

1. Suspension, Lower LH 5. Body Pivot, L.H. 9. Suspension, Lower RH 13. Anti-Sway Bar, L.H.2. Hoist Cyl., Top, L.H. 6. Body Pivot, R.H. 10. Hoist Cyl., Top, R.H. 14. Anti-Sway Bar, R.H.3. Hoist Cyl., Lower, L.H. 7. Suspension, Top, R.H. 11. Hoist Cyl., Lower, R.H.4. Suspension, Top, L.H. 8. Grease Supply Line 12. Axle Pivot Pin

M3-2 Lincoln Automatic Lube System M03001 12/98

1. Fill lube reservoir with lubricant, if necessary.

2. Remove plugs from all injector manifold dead endsand supply lines.

3. Turn air pump vent plug counterclockwise one fullturn. To expel trapped air between air pump andsupply line connection, run air motor until greaseflows freely from the vent plug. Close vent plugclockwise.

4. Continue to run air pump until grease flows fromany one plug opening in the system. Replace plugin this opening.

5. Repeat step 4 until all lines are full and all plugsreplaced.

NOTE: Fill each feed line with grease before connect-ing lines to the injector outlets and bearings. This willprevent having to cycle the individual injectors oncefor each 1.0 in. (25 mm) length of feed line betweenthe injector and bearing fitting.

System CheckoutTo check system operation (not including timer), pro-ceed as follows:

1. Lift the passenger seat and connect a jumper wirebetween ‘‘SOL’’ terminal and ‘‘LUBE SW’’ terminalon the 24 VDC solid state lube timer.

Turn keyswitch "ON". Pump should operate.

NOTE: If terminal post identification on the solid statetimer is not legible, refer to Figure 3-5 for terminalpositions.

2. Keep jumper wire connected until the pump stalls.

3. Disconnect jumper wire. System should vent. Turn keyswitch "OFF".

24 VDC Solid State Timer CheckTo check the solid state timer operation without waitingfor the normal timer setting, proceed as follows:

1. Remove timer dust cover.NOTE: The timer incorporates a liquid and dusttight cover which must be in place and securedat all times during truck operation.

2. Adjust timer to 5 minute interval setting.

3. The timer should cycle in five minutes if the truckis operating.

NOTE: If the timer check is being made on a cold start,the first cycle will be approximately double the nominalsetting. All subsequent cycles should be within theselected time tolerance.

4. Voltage checks at the timer should be accom-plished if the above checks do not identify theproblem.

a. Insure timer ground connection is clean andtight.

b. Using a Volt-Ohm meter, read the voltage be-tween positive and negative posts on the solidstate timer with the truck keyswitch "ON". Normal reading should be 18-26 VDC, depend-ing upon whether or not the engine is running.

24 VDC Solid State Timer Adjustment

The timer is factory set for a nominal 2.5 minute (offtime) interval. Dwell time is approximately 1 minute, 15seconds. A longer interval (off time) is obtained byturning the Selector knob (3, Figure 3-3) to the desiredposition .

NOTE: Set timer by turning the Selector knob (3) to the2.5 minute setting point. Then, turn the Selector clock-wise, one detent at a time, to the desired setting, oruntil the maximum limit of eighty minutes is reached.

The solid state timer is a sealed unit, do not attemptdisassembly.

FIGURE 3-3. TIMER (TOP COVER REMOVED)

1. Timer 3. Timer Selector2. Red LED (Light Emitting Diode) indicates pump solenoid is "ON".


Injectors (SL-1 Series " H")

Injector Specifications

a. Each lube injector services only one greasepoint. In case of pump malfunction, each injec-tor is equipped with a covered grease fitting toallow the use of external lubricating equipment.

b. Injectors are available in banks of two, three,four and five as well as single replacementunits.

c. Injector output is adjustable: Maximum output = 0.08 in3 (1.31 cc). Minimum output = 0.008 in3 (0.13 cc).

d. Operating Pressure:Minimum - 1850 psi (12 755 kPa)Maximum - 3500 psi (24 133 kPa)Recommended - 2500 psi (17 238 kPa)Maximum Vent Pressure - (Recharge) 600 psi (4 137 kPa)

Injector Adjustment

The injectors may be adjusted to supply from 0.008 in3

to 0.08 in3 (0.13 cc to 1.31 cc) of lubricant per injectioncycle. The injector piston travel distance determinesthe amount of lubricant supplied. This travel is in turncontrolled by an adjusting screw in the top of theinjector housing.

Turn the adjusting screw (1, Figure 3-4) counterclock-wise to increase lubricant amount delivered and clock-wise to decrease the lubricant amount.

When the injector is not pressurized, maximum injectordelivery volume is attained by turning the adjustingscrew (1) fully counterclockwise until the indicating pin(8) just touches the adjusting screw. At the maximumdelivery point, about 0.38 inch (9.7 mm) adjustingscrew threads should be showing. Decrease the deliv-ered lubricant amount by turning the adjusting screwclockwise to limit injector piston travel. If only half thelubricant is needed, turn the adjusting screw to thepoint where about 0.19 inch (4.8 mm) threads areshowing. The injector will be set at minimum deliverypoint with about 0.009 inch (0.22 mm) thread showing.

NOTE: The above information concerns adjustment ofinjector delivery volume. The timer adjustment shouldalso be changed, if overall lubricant delivery is too littleor too much. Injector output should NOT be adjustedto less than one-fourth capacity.

FIGURE 3-4. TYPE SL-1 INJECTOR (SINGLE) 1. Adjusting Screw 11. Spring Seat 2. Locknut 12. Plunger 3. Piston Stop Plug 13. Viton Packing 4. Gasket 14. Inlet Disc 5. Washer 15. Viton Packing 6. Viton O-Ring 16. Washer 7. Injector Body Assy. 17. Gasket 8. Piston Assembly 18. Adapter Bolt 9. Fitting Assembly 19. Adapter10. Plunger Spring 20. Viton Packing

NOTE: The Piston Assembly (8) has a visible indicatorpin at the top of the assembly to verify the injectoroperation.

FIGURE 3-4A. INJECTOR (MANIFOLD TYPE)


INJECTOR OPERATION

STAGE 1.

The injector piston (2) is in its normal or"rest" position. The discharge chamber (3)is filled with lubricant from the previous cy-cle. Under the pressure of incoming lubri-cant (6), the slide valve (5) is about to openthe passage (4) leading to the measuringchamber (1) above the injector piston (2).

STAGE 2.

When the slide valve (5) uncovers the pas-sage (4), lubricant (6) is admitted to themeasuring chamber (1) above the injectorpiston (2) which forces lubricant from thedischarge chamber (3) through the outletport (7) to the bearing.

STAGE 3.

As the injector piston (2) completes itsstroke, it pushes the slide valve (5) past thepassage (4), cutting off further admission oflubricant (6) to the passage (4) and meas-uring chamber (1). The injector piston (2)and slide valve (5) remain in this positionuntil lubricant pressure in the supply line (6)is vented (relieved at the pump).

STAGE 4.

After venting, the injector spring expands,causing the slide valve (5) to move, so thatthe passage (4) and discharge chamber (3)are connected by a valve port (8). Furtherexpansion of the spring causes the pistonto move upward, forcing the lubricant in themeasuring chamber (1) through the pas-sage (4) and valve port (8) to refill the dis-charge chamber (3).

Injector is now ready for the next cycle.


TROUBLESHOOTING CHARTPOSSIBLE CAUSES SUGGESTED CORRECTIVE ACTION

TROUBLE: Pump Does Not Operate.

Low air pressure.

Lube system not grounded.

Electrical power loss.

Timer malfunction.

Solenoid valve malfunctioning.

Pump malfunction.

Adjust air pressure to 60 -- 65 psi (414 -- 448 kPa), ifnecessary [90 psi (621 kPa) during cold weather].

Correct grounding connections to pump assembly andtruck chassis.

Locate cause of power loss and repair. 24 VDC powerrequired; be sure keyswitch is "ON".

Replace timer assembly

Replace the solenoid valve assembly

Replace pump assembly

NOTE: On intial startup of the lube system, the timing capacitor will not contain a charge, therefore the first timingcycle will be about double in length compared to the normal interval. Subsequent timer cycles should be as specified.

TROUBLE: Pump Will Not Prime

Low lubricant supply.

Dirt in reservoir, pump inlet clogged.

Air trapped in pump.

Check lubricant level in reservoir and service reservoirwith specified grease until grease weeps from ventplug.

Clean reservoir completely, remove and clean pumpassembly thoroughly.

Open vent plug counterclockwise with pump running.When grease flows freely from vent, close vent plugclockwise.

NOTE: System air applied to the lube system air pump is also applied to the vent valve. When the pump is operating,air pressure keeps the vent valve closed and grease is directed from the pump outlet and to the injectors. When airsupply to the air motor is interrupted, the vent valve opens and supply pressure vents back to the reservoir.

Safety unloader valve faulty. Replace safety unloader valve.

NOTE: The safety unloader valve prevents buildup of excessively high pressure in the lube system which coulddamage components. This valve is factory preset to open between 3750 - 4250 psi (25.9 - 29.3 MPa). The valve is notserviceable, nor is it adjustable.

Outlet check valve clogged. Remove check valve from pump outlet, clean thor-oughly or replace.



TROUBLE: Pump Will Not Build Pressure

Pump not primed.

Air trapped in lubricant supply line.

Lubricant supply line leaking.

Vent valve leaking.

Pump cylinder scored, by-passing air.

See items in ‘‘Pump Will Not Prime’’.

Prime system to remove trapped air.

Check lines and connections to repair leakage.

Clean or replace vent valve.

Repair or replace pump cylinder or pump assembly.

TROUBLE: Injector Indicator Stem Does Not Operate

NOTE: Normally, during operation, the injector indicator stem (Figure 3-4) will move into the body of the injector whenpressure builds properly. When the system vents (pressure release) the indicator stem will again move out into theadjusting yoke.

Malfunctioning injector - usually indicated by the airpump building pressure and then venting.

All injectors inoperative - pump build up not sufficientto cycle injectors.

Replace individual injector assembly.

Service and/or replace pump assembly.

FIGURE 3-5. TYPICAL ELECTRICAL HOOKUP FOR AUTOMATIC LUBE1. Solenoid Air Valve 5. Fuse Holder 9. Solenoid 13. Battery2. Main Air Supply 6. Keyswitch 10. Relay 14. Keyswitch3. To Air Pump Motor 7. To Battery (+ ) 11. Timer (solid State) 15. 7.5 Amp Fuse4. Timer * 8. To Ground (-) 12. Timer (Housing)* Keyswitch (6) must be closed ("ON") to energize Timer (4).


NOTES


WIGGINS QUICK FILL FUEL SYSTEM

FUEL RECEIVERThe fuel receiver (3, Figure 5-1) is normally mountedon the fuel tank (1). Optional locations are the left handframe rail (Figure 5-3) or at the Service Center in front.

Keep the cap on the receiver to prevent dirt build up invalve area and nozzle grooves. If fuel spills from tankbreather valve, or tank does not completely fill, checkbreather valve to see that float balls are in place andoutlet screen is clean. If valve is operating properly, theproblem will be with the fuel supply system.

FIGURE 5-1. FUEL TANK BREATHER & RECEIVER INSTALLATION1. Fuel Tank2. Breather Valve

3. Fuel Receiver4. Fuel Level Gauge

NOTE: This Illustration Represents a Typical Installation. Fuel tank may vary in size, shape and location depending on truck model.

M05002 10/96 Wiggins Quick Fill Fuel System M5-1

TANK BREATHER VALVE

Removal

Unscrew breather valve (2, Figure 5-1) from tank (1).

Installation

Screw breather valve into tank.

Disassembly

1. Remove spring clamp (4, Figure 5-2) from outlet.

2. Pull off rubber cover and screen (3).

3. Unscrew nut (5) from top of breather valve. Re-move cover (6), spring (7), and steel ball (8).

4. Slide valve assembly (9) from housing.

5. Disengage tapered spring (1) containing threeballs (2) from valve stem.

Assembly

1. Clean and inspect all parts. If valve, body, orsprings are damaged, replace complete breathervalve.

2. Install in order; tapered spring, one steel ball, onecork ball and one hollow aluminum ball.

3. Engage three coils of spring on small end of valvestem with hollow aluminum ball.

4. Install valve into housing.

5. Place steel ball (8) on top of valve. Install spring(7).

6. Place cover (6) over spring. Screw on large nut (5).

7. Install screen and rubber cover (3) over outlet.

8. Install spring clamp (4).

FIGURE 5-2. BREATHER VALVE

1. Tapered Spring2. Float Balls3. Cover and Screen4. Spring Clamp5. Nut

6. Cover7. Spring8. Steel Ball9. Valve Assembly

M5-2 Wiggins Quick Fill Fuel System M05002 10/96

LEFT SIDE FILL This location permits fueling the truck from the left side. Keep the cap on the receiver to prevent dirt build up in

valve area and nozzle grooves. If fuel spills from tankbreather valve, or tank does not completely fill, checkbreather valve to see that float balls are in place andoutlet screen is clean. If valve is operating properly, theproblem will be with the fuel supply system.

FIGURE 5-3. LEFT SIDE FILL1. Hydraulic Tank 3. Frame Rails 5. Filler Cap 7. Refueling Box2. Filler Hose 4. Fuel Tank 6. Receiver Assembly 8. Capscrew

9. Tapped BarNOTE: This Illustration Represents a Typical Installation. Installation may vary depending on truck model.

M05002 10/96 Wiggins Quick Fill Fuel System M5-3

NOTES

M5-4 Wiggins Quick Fill Fuel System M05002 10/96

BUCKEYE QUICK FUEL SYSTEM

FUEL TANK BREATHER VALVE

Maintenance

Normal maintenance involves cleaning or replacementof the breather valve filter during 1000 hour servicing.Operation in extremely dusty conditions may requiremore frequent cleaning or replacement intervals.

Filter Service

1. Remove three capscrews (7, Figure 5-1) on venthousing.

2. Remove housing (1) and filter (3).

3. Clean the filter in solvent and blow dry with com-pressed air.

4. Inspect filter for damage and replace if necessary.

5. Install filter on seat (6).

6. Inspect the housing O-ring seal (8) and replace ifnecessary.

7. Install the housing and secure in place with cap-screws (7).

Disassembly

1. Remove breather valve assembly from the fueltank. (Refer to Figure 5-2.)

2. Loosen three capscrews (7, Figure 5-1) and re-move vent housing (1).

3. Remove filter (3).

4. Compress the spring (12, Figure 5-1) and removethe cotter pin (17).

5. Remove the retaining washer (16), spring and balls(13, 14, and 15).

Inspection

1. Inspect filter and clean or replace as required.

2. Clean all parts thoroughly and inspect for damage.

Assembly

1. Assemble using new O-ring seals.

2. Install filter (3) and housing (1).

3. Insert balls in order as shown in Figure 5-1.

a. Install aluminum ball.

b. Install plastic ball.

c. Install steel ball.

4. Insert spring (12) and retaining washer (16). Com-press spring to insert cotter pin (17).

5. Install assembly in fuel tank.

91492

FIGURE 5-1. FUEL TANK BREATHER VALVE

1. Vent Housing2. Inner Tube3. Filter4. Cotter Pin5. O-ring6. Seat7. Capscrew8. O-ring9. Vent Base

10. Nipple11. Outer Tube12. Spring13. Aluminum Ball14. Plastic Ball15. Steel Ball16. Retaining Washer17. Cotter Pin

M05003 5/90 Buckeye Quick Fill Fuel System M5-1

FUEL RECEIVERThe fuel receiver (3, Figure 5-2) is mounted on the fueltank (2). Keep the cap on the receiver to prevent dirtbuild-up during truck operation. If fuel spills frombreather valve or tank does not fill completely, checkbreather to see that the balls are in place and the filteris clean.

91493

FIGURE 5-2. FUEL TANK BREATHER ANDRECEIVER INSTALLATION

1. Breather Valve2. Fuel Tank

3. Fuel Receiver4. Fuel Level Gauge

NOTE: This Illustration Represents a Typical Installation.

Fuel tank may vary in size, shape and location depending on truck model.

M5-2 Buckeye Quick Fill Fuel System M05003 5/90

ENGINE COOLANT AND OIL HEATERS

ENGINE COOLANT HEATERTo aid in cold weather starting, the truck can beequipped with a cooling system heater. One high ca-pacity coolant heating unit is mounted on the right sideof the engine block. The system includes:

• Heaters

• Thermostat

• Hoses

• 220 volt Receptacle

• Power Cables, Thermostat Wiring, and Junc-tion Box

Heater operation is controlled by a thermostatmounted on the intake end of the heating unit. Thethermostat turns the heater ‘‘On’’ at 120°F (48°C) and‘‘Off’’ at 140°F (60°C).

Do not operate engine while the cooling systemheater is operating as it will cause a lack of circu-lation in the heater and burn out the heating ele-ments.

Maintenance

To check for operation of the heating unit, the outletwater hose should feel warm to the touch.

1. Check all electrical connections to insure properconnections are made.

2. Check for a burned out heating element (4, Figure7-1)(Do not remove heating unit from the truck).

a. Remove the two Phillips head screws and slideend cover (5) out of the way.

b. Connect a voltmeter at the two electrical termi-nals (6) and check for operating voltage (220 to230 volts) while coolant temperature is below120°F (48°C). If correct voltage is present, theheating element is defective and should bereplaced.

3. If correct voltage (measured above) is not read atheating element terminals, the thermostat is de-fective and should be replaced.

HEATING ELEMENT

Removal

1. Disconnect the external power source at the plug-in receptacle.

2. Open petcock valve on lower radiator coolant tubeand drain coolant. Cooling system holds approxi-mately 48 gallons (182 L.) of coolant.

3. Remove heating element.

a. Remove the two Phillips head screws fromcover (5) at power cable entry. Slide cover outof the way.

b. Disconnect the two electrical leads (6) andremove heating element (4) from the cartridge.

Installation

1. Install new heating element.

91464

FIGURE 7-1. COOLANT HEATER

1. Thermostat2. Heater Assembly3. Water Outlet Port

4. Heating Element5. Cover6. Terminals

M07006 9/90 Engine Coolant Heater M7-1

a. Cover the new heating element threads with ananti-seize thread compound.

b. Screw heating element into cartridge andtighten securely to insure against leaks.

2. Connect the electrical leads.

3. Slide element cover into position and secure withscrews.

4. Close drain petcock and refill system with coolant.Refer to section "P", Lubrication And Service forproper coolant and mixtures.

5. Start engine, allow coolant to circulate 10-15 min-utes to eliminate trapped air in cooling system.Shut down engine.

6. Check for leaks and proper coolant level.

7. Plug in the external power source. After allowingtime for the element to warm up, outlet hoseshould feel warm to the touch.

THERMOSTAT

Removal

1. Disconnect the external power source at the plugin receptacle.

NOTE: It is not necessary to remove the thermostatassembly from the heater.

2. Remove the two screws and slide cover (1,Figure7-2) out of the way.

3. Disconnect the two electrical leads.

4. Loosen the two setscrews (4) and remove thetemperature sensing unit (2).

Installation

1. Install a new temperature sensing unit and securein place with two setscrews (4).

2. Connect the electrical leads.

3. Move cover (1) into position and secure in placewith screws.

4. Plug in the external power source.

After allowing time for the element to warm up, outlethose should feel warm to the touch.

91465

FIGURE 7-2. THERMOSTAT ASSEMBLY

1. Cover2. Temperature Sensing

Unit

3. Housing4. Setscrew

M7-2 Engine Coolant Heater M07006 9/90

TRANSMISSION AND ENGINE OILHEATERS

One 230 volt, 600 watt engine oil heater is located inthe engine and transmission oil pans. Operation of theoil heaters is controlled by the coolant system heaterthermostat.

Troubleshooting

Operation of the heaters can be checked by touchingeach mounting boss (3, Figure 7-3) on the oil pan afterallowing time for the heaters to warm up:

1. If the boss (3, Figure 7-3) feels warm to the touch,the heater is functioning.

2. If no heat is detected, verify proper operatingvoltage (220 to 230 volts) at the heating elementleads.

3. If voltage is not present, check the thermostatcircuit at the engine coolant heater. (Refer to‘‘Engine Coolant Heater’’.) Also check circuits be-tween heaters and the plug-in receptacle.

4. If no heat is detected, but voltage is correct, theheating element must be replaced.

HEATING ELEMENT

Removal

1. Disconnect the external power source at the plug-in receptacle.

NOTE: Heater element replacement can be accom-plished without draining the crankcase or transmis-sion oil by disassembling all parts from the elementcover. Figures 7-4 and 7-5 show the complete heaterassembly removed from the pan.

2. Remove cap (7, Figure 7-4), remove connectors(9) and disconnect wires (8).

3. Remove cord grip cap (2) and remove power cordfrom the housing.

4. Remove the heater housing (5) from the elementcover (6).

5. Loosen the setscrew (3, Figure 7-5) and removethe heater element (2) from the cover (1).

81265

FIGURE 7-3. ENGINE OIL HEATER

1. Heater Assembly2. Power Cord

3. Oil Pan MountingBoss

81266

FIGURE 7-4. HEATER ASSEMBLY

1. Power Cord2. Cord Grip Cap3. Washer4. Rubber Bushing5. Housing

6. Element Cover7. Housing Cap8. Electrical Leads9. Wire Connectors

M07006 9/90 Engine Coolant Heater M7-3

Installation

1. Install a new heater element and secure in placewith the setscrew (3, Figure 7-5).

2. Coat the threads of the element cover (6, Figure7-4) with an anti-seize compound and install intohousing (5).

3. Insert the power cord (1), cord grip bushing (4),washer (3) and cap (2) into the housing.

4. Twist the wires together and place a screw-onconnecter on each pair.

5. Adjust the power cord and tighten the cord gripcover.

6. Replace the housing cap.

7. If any oil was drained, refill with proper oil. Refer tosection "P", Lubrication And Service for proper oil.

FIGURE 7-5. HEATING ELEMENT REMOVAL

1. Element Cover2. Heating Element

3. Element RetainingSetscrew

81268

1. Junction Box

2. Terminal Strip

FIGURE 7-6 WIRING DIAGRAM

M7-4 Engine Coolant Heater M07006 9/90

SPECIAL TOOLS

SECTION C

Special tools have been referenced throughout thismanual. The tools shown here will be listed under thesection where they were used. Dimensioned toolsmaybe manufactured locally and non-dimensionedtools may be purchased under the indicated part num-ber.

Unless noted for a specific application, these tools maybe used for both the 140M and 210M HAULPAK®

Trucks.

FIGURE 8-1. CUMMINS ENGINE LIFTING TOOL

M08003 9/90 Special Tools M8-1

SECTION G

FIGURE 8-2.

M8-2 Special Tools M08003 9/90

SECTION G

FIGURE 8-3.


SECTION G

FIGURE 8-4.


SECTION G

FIGURE 8-5.


SECTION G

FIGURE 8-6.


FIGURE 8-7.

( USED WITH TORQUING BASE SS 1122)

SECTION G


SECTION G

FIGURE 8-8.


SECTION G

FIGURE 8-9.

( USED WITH TORQUING BASE SS 1121)


SECTION G

FIGURE 8-10.


SECTION G

FIGURE 8-11. SS1128 DIFFERENTIAL LIFTING BRACKET

FIGURE 8-12.


SECTION G

FIGURE 8-13.

FIGURE 8-14.

FIGURE 8-15.

FIGURE 8-16.


SECTION H SECTION J

SECTION J SECTION J

BRAKE HUB RETAINING BRACKET(140M and 210M)

FIGURE 8-17. VD4665 NITROGEN CHARGING KIT

FIGURE 8-18.

FIGURE 8-19.

FIGURE 8-20. EB1722 WEAR INDICATOR FOR OIL DISC BRAKES


SECTION J

FIGURE 8-21.


SECTION L

PRESSURE SWITCH TESTERKENT-MOORE PART NUMBER J-33884-4

Tester may be purchased from:

Kent-Moore Heavy Duty Div.Sealed Power Corp.29784 Little MackRoseville, MI 48066-9984Telephone No. (313) 774-9500Telex: 23-5377Telex outside North America: 023-5377

FIGURE 8-22.

FIGURE 8-23.


SECTION L

FIGURE 8-24.


SECTION L

FIGURE 8-25.

FIGURE 8-26.

FIGURE 8-27.

FIGURE 8-28.


NOTES


AIR CONDITIONING SYSTEMEnvironmental Impact

Environmental studies have indicated a weakening ofthe earth’s protective Ozone (O3) layer in the outerstratosphere. Chloro-flouro-carbon compounds(CFC’s), such as R-12 refrigerant (Freon®), commonlyused in mobile equipment air conditioning systems,has been identified as a possible contributing factor tothe Ozone depletion.

Consequently, legislative bodies in more than 130countries have mandated that the production and dis-tribution of R-12 refrigerant be discontinued after 1995.In addition, the practice of releasing refrigerant to theatmosphere during the charging/recharging proce-dure is now prohibited.

FIGURE 9-1. BASIC AIR CONDITIONING SYSTEM (TYPICAL)

1. Blower Switch2. Thermostatic Switch3. Battery Supply4. Circuit breaker5. Blower

6. Temperature Sensor7. Evaporator8. Expansion Valve9. Suction Line

10. Test gauges & Manifold11. Compressor12. Refrigerant Container13. Magnetic Clutch

14. Compressor Drive Pulley15. Receiver/Drier16. Discharge Line17. Condenser

M09003 11/95 Air Conditioning System M9-1for R-12 Refrigerant

These new restrictions require the use of new equip-ment and new procedures which are significantly dif-ferent from those traditionally used in air conditioningservice techniques. The use of new equipment andtechniques permits the complete recovery of refriger-ant, which will not only help to protect the environment,but through the ‘‘re-cycling’’ of the refrigerant, will pre-serve the physical supply as well as help to reduce thecost of the refrigerant.

OPERATOR CAB AIR CONDITIONING

Mining and construction vehicles have unique charac-teristics of vibration, shock-loading, operator changes,and climate conditions that present different designand installation problems for Air Conditioning systems.Off-highway equipment, in general, is unique enoughthat normal automotive or highway truck engineeringis not sufficient to provide the reliability to endure thevarious work cycles encountered.

Air conditioning is a form of environmental control. Asapplied to the cab, it refers to the control of tempera-ture, humidity, cleanliness, and circulation of air. In thebroad sense, a heating unit is as much an air condi-tioner as is a cooling unit. The term ‘‘Air Conditioner’’is commonly used to identify an air cooling unit. To beconsistent with common usage, the term ‘‘Air Condi-tioner’’ will refer to the cooling unit utilizing the princi-ples of refrigeration; sometimes referred to as theevaporator unit.

The cab tightness, insulation, and isolation from heatsources is very important to the efficiency of the sys-tem. It is advisable to close all vents, even the intakesof pressurization systems, when there are high humid-ity conditions.

The general cleanliness of the system and componentsis important. Dust or dirt collected in the condenser,evaporator, or air filters decreases the system’s coolingcapacity.

The refrigerant pump (compressor), condenser,evaporator units, hoses and fittings must be installedclean and tight and be capable of withstanding thestrain and abuse they are subjected to from off-high-way vehicles.

Equipment downtime costs are high enough to encour-age service areas to perform preventive maintenanceat regular intervals on vehicle air-conditioning systems.(Cleaning, checking belt tightness, and operation ofelectrical components).

PRINCIPLES OF REFRIGERATIONA review of the principles of air conditioning will relatethe function of the components, the technique oftrouble shooting and the corrective action necessaryto keep the A/C unit into top operating efficiency.

Too frequently, the operator and the serviceman over-look the primary fact that no A/C system will functionproperly unless it is operated within a completely con-trolled cab environment. The circulation of air must bea directed flow. The cab must be sealed against seep-age of ambient air. The cab interior must be maintainedfor cleanliness, dust, and dirt which, if picked up in theair system, will clog the intake side of the evaporatorcoil.

REFRIGERATION - THE ACT OF COOLING

• There is no process for producing cold; there isonly heat removal.

• Heat is always drawn toward cold objects. Thisprinciple is the basis for the operation of a coolingunit. As long as one object has a temperaturelower than another, this heat transfer will occur.

• Temperature is the measurement of the intensityof heat in degrees. The most common measuringdevice is the thermometer.

• All objects have a point at which they will turn tovapor. Water boiling is the most common exam-ple of heating until vapor is formed. Boiling is arapid form of evaporation. Steam is a great dealhotter than boiling water. The water will not in-crease in temperature once brought to a boil. Theheat energy is used in the vaporization process.The boiling point of a liquid is directly affected bypressure. By changing pressure, we can controlthe boiling point and temperature at which avapor will condense. When a liquid is heated andvaporizes, the gas will absorb heat withoutchanging pressure. This gas is in a superheatedcondition.

• Reversing the process, when heat is removedfrom water vapor, it will return to the liquid state.Heat from air is attracted to a cooler object.Usually the moisture in the cooled air will con-dense on the cooler object.

• Refrigerant: Only R-12 refrigerant should be usedin mobile systems designed for R-12. Do not mix refrigerants! Damage to equip-ment and components will result!

M9-2 Air Conditioning System M09003 11/95for R-12 Refrigerant

• R-12 refrigerant has a boiling point of -21°F (at-mospheric pressure). If released in a room, itwould absorb heat from the air and immediatelyvaporize. R-12, because of its low boiling point,has a great capacity for heat absorption.

THE REFRIGERATION CYCLE

In an air conditioning system, the refrigerant is circu-lated under pressure through the five major compo-nents in a closed circuit. At these points in the system,the refrigerant undergoes predetermined pressure andtemperature changes.

The compressor (refrigerant pump) takes in low pres-sure heat laden refrigerant gas through the suctionvalve (low side), and as its name indicates, pressurizesthe heat laden refrigerant and forces it through thedischarge valve (high side) on to the condenser.

Ambient air, passing through the condenser removesthe heat from the circulating refrigerant resulting in theconversion of the refrigerant from gas to liquid.

The liquid refrigerant moves on to the filter-receiverdrier where impurities are filtered out, and moistureremoved. This component also serves as the tempo-rary storage unit for the liquid refrigerant.

The liquid refrigerant, still under high pressure, thenflows to the expansion valve. This valve meters theamount of refrigerant entering the evaporator. As therefrigerant passes through the valve, it becomes a lowtemperature, low pressure liquid and saturated vapor.

The remaining low pressure liquid immediately startsto boil and vaporize as it approaches the evaporator,causing it to become cold. The hot, humid air of thecab is pulled through the evaporator by the evaporatorblower. Since the refrigerant is colder than the air, itabsorbs the heat from the air producing cool air whichis pushed back into the cab. The moisture in the aircondenses upon movement into the evaporator anddrops into the drain pan from which it drains out of thecab.

The cycle is completed when the heated low pressuregas is again drawn into the compressor through thesuction side.

This simplified explanation of the principles of refrigera-tion does not call attention to the fine points of refrig-eration technology and the design of air conditioningsystems. Some of these will be covered in the followingdiscussion of the components, controls, and tech-niques involved in preparing the unit for efficient opera-tion.

AIR CONDITIONER SYSTEMCOMPONENTS

COMPRESSOR (Refrigerant Pump)

The compressor separates the low pressure and thehigh pressure sides of the system. It concentrates therefrigerant returning from the evaporator (low side)creating a temperature much higher than the outsideair temperature. The high temperature differential be-tween the refrigerant and the outside air is necessaryto aid rapid heat flow in the condenser from the hotrefrigerant gas to much cooler outside air.

To create high pressure concentration, the compres-sor draws in refrigerant through the suction valve andforces it out through the discharge valve. During thesuction part of the cycle, the reed valve is opened toallow low pressure gas to enter. During discharge,refrigerant is forced through the discharge valve.

The compressor is driven by the engine through av-belt driving an electrically operated clutch mountedon the compressor drive shaft.

SERVICE VALVES

Service valves are provided for servicing the unit. Amanifold gauge set is connected into the system at theservice valve ports and all procedures, such as dis-charging, evacuating and charging the system, areperformed through the service valves.

CONDENSER

The condenser receives the high pressure, high-tem-perature refrigerant vapor from the compressor andcondenses it to high pressure, hot liquid.

It is designed to allow heat movement from the hotrefrigerant vapor to the cooler outside air. The coolingof the refrigerant changes the vapor to liquid. Heatexchange is accomplished using cooler air flowingthrough the condenser. The condenser can be cooledwith ram air provided by vehicle movement and some-times aided by electric or hydraulic fans or by using theair movement provided by the radiator fan.

Ram air condensers depend upon the vehicle move-ment to force a large volume of air past the fins andtubes of the condenser. The condenser is usually lo-cated in front of the radiator or on the roof of the truck.


Refrigerant temperature in the condenser varies from120° to 170°F (49° to 77° C) with pressure ranging from150 to 300 psi. (27 to 54 kg/cm2).

Condensing of the refrigerant is the change of state ofthe refrigerant from a vapor to a liquid. The action isaffected by the pressure of the refrigerant in the coiland air flow through the condenser. Condensing pres-sure in an A/C system is the controlled pressure of therefrigerant which affects the temperature at which itcondenses to liquid, giving off large quantities of heatin the process. The condensing point is sufficiently highto create a wide temperature differential between thehot refrigerant vapor and the air passing over thecondenser fins and tubes. This difference permits rapidheat transfer from the refrigerant to ambient air.

FILTER RECEIVER-DRIER

The receiver-drier is an important part of the air condi-tioning system. The drier receives the liquid refrigerantfrom the condenser and removes any moisture andforeign matter present which may have entered thesystem. The receiver section of the tank is designed tostore extra refrigerant until it is needed by the evapo-rator. The storage of this refrigerant is temporary andis dependent on the demand of the expansion valve.

A desiccant is a solid substance capable of removingmoisture from gas, liquid or solid. It is held in placewithin the receiver between two screens, which alsoact as strainers. Sometimes it is simply placed in ametal mesh or wool felt bag. Filtering is accomplishedby a separate strainer screen on the pickup tube.

Some systems may utilize an accumulator instead of areceiver-drier. If an accumulator is used, an expansion(fixed-orifice) tube is used instead of the thermostaticexpansion valve described below. When used, theexpansion tube is located inside the inlet tube of theevaporator and is used to restrict, but still allow acontinuous flow of refrigerant to the evaporator coil.

Fusible Pressure Relief Plug

Some receiver driers have a fusible plug which meltsbetween 218° - 230° F (103° - 110° C). This plug servesas a safety valve in the event the condenser safetyswitch malfunctions, allowing the relief of excessiveinternal pressures which would damage the system.Some systems employ a spring loaded pressure reliefvalve which performs the same function.

THERMOSTATIC EXPANSION VALVE

The thermostatic expansion valve controls the amountof refrigerant entering the evaporator coil. Both inter-nally and externally equalized valves are used.

The expansion valve is located near the inlet of theevaporator and provides the functions of throttling,modulating, and controlling the liquid refrigerant to theevaporator coil.

The refrigerant flows through a restriction, creating apressure drop across the valve. Since the expansionvalve also separates the high side of the system fromthe low side, the state of the refrigerant entering thevalve is warm to hot high pressure liquid; exiting it islow pressure liquid and gas. The change to low pres-sure allows the flowing refrigerant to immediately beginchanging to gas as it goes toward the evaporator.

The amount of refrigerant metered into the evaporatorvaries with different heat loads. The valve modulatesfrom wide open to the nearly closed position, seekinga point between for proper metering of the refrigerant.

The expansion valve is controlled by both the tempera-ture of the power element bulb and the pressure of theliquid in the evaporator. As the load increases, the valveresponds by opening wider to allow more refrigerantto pass into the evaporator. As the load decreases, thevalve reacts and allows less refrigerant into the evapo-rator. It is this controlling action that provides theproper pressure and temperature control in the evapo-rator.

Some systems may use an internally equalized, blocktype expansion valve. With this type valve, the refriger-ant leaving the evaporator coil is also directed backthrough the valve so the temperature of the refrigerantis monitored internally rather than by a remote sensingbulb.

NOTE: It is important that the sensing bulb, if installed,is tight against the output line and protected fromambient temperatures with insulation tape.

EVAPORATOR

The evaporator cools and dehumidifies the air beforeit enters the cab. Cooling a large area requires thatlarge volumes of air be passed through the evaporatorcoil for heat exchange. Therefore, a blower becomesa vital part of the evaporator assembly. It not only drawsheat laden air into the evaporator, but also forces thisair over the evaporator fins and coils where the heat issurrendered to the refrigerant. The blower forces thecooled air out of the evaporator into the cab.


Heat exchange, as explained under condenser opera-tion, depends upon a temperature differential of the airand the refrigerant. The greater the temperature differ-ential, the greater will be the amount of heat exchangedbetween the air and the refrigerant. A high heat loadcondition, as is generally encountered when the airconditioning system is turned on, will allow rapid heattransfer between the air and the cooler refrigerant.

The change of state of the refrigerant in and goingtoward the evaporator coil is as important as that of theair flow over the coil. All or most of the liquid that didnot change to vapor in the expansion valve or connect-ing tubes boils (expands) and vaporizes immediatelyin the evaporator, becoming very cold. As the processof heat loss from the air to the evaporator coil surfaceis taking place, any moisture (humidity) in the air con-denses on the cool outside surface of the evaporatorcoil and is drained off as water.

At atmospheric pressure, refrigerant boils at a pointlower than water freezes. Therefore, the temperature inthe evaporator must be controlled so that the watercollecting on the coil surface does not freeze on andbetween the fins and restrict air flow. The evaporatortemperature is controlled through pressure inside theevaporator, and temperature and pressure at the outletof the evaporator.

Superheat

The liquid refrigerant admitted to the evaporator coil isusually completely vaporized before reaching the coiloutlet. Since liquid R-12 is vaporized at relatively lowtemperature, it can be seen that the vapor remainscold, even though the liquid is completely evaporated.

The cold vapor flowing through the remainder of thecoil continues to absorb heat, becoming superheated.This means that the temperature of the refrigerant hasbeen raised above the point at which it evaporatedwithout an increase in pressure.

As the refrigerant vaporizes through the absorption ofthe heat in the evaporator, the temperature of the vaporrises at the coil outlet and reaches a difference of about5° F (3° C) between the vaporizing temperature andoutlet refrigerant temperature.

The difference in this temperature is called superheat.All expansion valves are adjusted at the factory tooperate under superheat conditions present in theparticular type of unit for which they are designed.

ELECTRICAL CIRCUITThe air conditioner’s electrical circuit is fed from anaccessory circuit and is normally protected with a30-ampere fuse or circuit breaker.

The blower control is a switch which provides a rangeof blower speeds from fast to slow. When the blowerswitch is turned on, current is fed to the thermostat.Once the blower is turned on, fan speeds may bechanged without affecting the thermostat sensinglevel.

The thermostat reacts to changing temperatures whichcause electrical contacts to open and close. Thethermostat has a capillary tube extended into theevaporator coil to sense temperature.

When the contacts are closed, current flows to theclutch field and energizes the clutch, causing thecrankshaft to turn which starts the refrigeration cycle.When the temperature of the evaporator coil drops toa predetermined point, the contacts open and theclutch disengages.

When the clutch is disengaged, the blower remains atthe set speed. After the evaporator temperature risesabout twelve degrees above the cutout point, the con-tacts in the thermostat close and the refrigeration cycleresumes.

THERMOSTAT

An electromagnetic clutch is used on the compressorto provide a means of constant temperature control ofthe cab. The clutch is controlled by a thermostat in theevaporator which is set initially by the driver to a pre-determined point. Coil temperature is then maintainedby the cycling action of the clutch.

The thermostat is simply a thermal device which con-trols an electrical switch. When warm, the switch isclosed; when cold, it is open. Most thermostats have apositive OFF position as a means to turn the clutch OFFregardless of temperature.

The bellows type thermostat is connected to a capillarytube filled with refrigerant. The capillary tube is at-tached to the bellows inside of the thermostat. Expan-sion of the gases inside the capillary tube exertspressure on the bellows, which in turn closes the con-tacts at a predetermined temperature.


COMPRESSOR CLUTCH

An electromagnetic clutch is used in conjunction withthe thermostat to disengage the compressor when it isnot needed, such as when a defrost cycle is indicatedin the evaporator, or at other times when the air condi-tioner is not being used.

The stationary field clutch is the most desirable typesince it has fewer parts to wear out. The field is mountedto the compressor by mechanical means dependingon the type field and compressor. The rotor is held onthe armature by a bearing and snap rings. The arma-ture is mounted on the compressor crankshaft.

When no current is fed to the field, there is no magneticforce applied to the clutch and the rotor is free to turnon the armature, which remains stationary on thecrankshaft.

When the thermostat or switch is closed, current is fedto the field. This sets up a magnetic force between thefield and armature, pulling it into the rotor. When thearmature becomes engaged with the rotor, the com-plete unit rotates while the field remains stationary. Thiscauses the compressor crankshaft to turn, starting therefrigeration cycle.

When the switch or thermostat is opened, current isremoved. The armature snaps back out and stopswhile the rotor continues to rotate. Pumping action ofthe compressor is stopped until current is again ap-plied to the field.

SAFETY SWITCHES (Not Used In All Systems)

Condenser Safety Switch (Overheat Switch)

The condenser safety switch shuts off the air condi-tioner when the refrigerant temperature reaches ap-proximately 190° F (88° C) at the outlet of thecondenser.

Since the refrigerant will break down at about 232° F(111° C), the 190° F (88° C) cut off point gives ampleprotection. The switch is fully automatic and will turnthe unit back on when the refrigerant temperaturereaches 150°F (66° C).

Refrigerant Loss (Low Pressure) Switch

The refrigerant loss switch prevents the clutch fromengaging in the event the system loses its refrigerantcharge, or if the refrigerant pressure drops below 5 psi(0.89 Kg /cm2).This is a simple breaker type switch at5 psi (0.89 Kg/cm2).


SYSTEM SERVICINGServicing an air conditioning system really meansclosely monitoring refrigerant flow. For this reason, thefollowing procedures deal extensively with the properuse, handling, care and safety factors involved in therefrigerant quality and quantity in an air conditioningsystem.

Because the refrigerant in an air conditioning systemmust remain pressurized and sealed within the unit tofunction properly, safety is a major consideration whenanything causes this pressurized, sealed condition tochange. The following warnings are provided here toalert you to their importance BEFORE you begin learn-ing the correct procedures. Read, remember, and ob-serve each warning as you begin actual systemservicing.

NOTE: If the mine operates a fleet with some trucksusing R-12 and others using the new R-134a refriger-ant, it is essential that servicing tools (gauge sets,charging equipment, recovery/recycle equipment etc.)be dedicated to one type refrigerant only to preventcross contamination.

Federal regulations prohibit venting R-12 or otherrefrigerants into the atmosphere. An SAE and ULapproved recovery/recycle station must be used toremove refrigerant from the AC system.

Although accidental release of refrigerant is a re-mote possibilty when correct service proceduresare followed, the following warnings must be ob-served when servicing AC systems:

Provide appropriate protection for your eyes (gog-gles or face shield) when working around air con-diitioning refrigerant.

Because R-12 refrigerant boils at a normal sea leveltemperature of -21.6° F (-30° C), a drop of the liquidon your skin will cause frostbite. Wear gloves andexercise extreme care when handling refrigerant.

If even the slightest trace of refrigerant enters youreye, flood the eye immediately with cool water andseek medical attention as soon as possible.

When exposed to flames or sparks, the compo-nents of R-12 refrigerant change and becomedeadly phosgene gas. This poison gas will damagethe respiratory system if inhaled. NEVER smoke inan area where R-12 is used or stored.

Never direct a steam cleaning hose or torch indirect contact with components in the air condi-tioning system. Localized heat can raise the pres-sure to a dangerous level.

Do not heat or store refrigerant containers above120° F (49° C).

Do not flush or pressure test the system using shopair or other compressed air sources. Shop airsupplies contain moisture and other contaminantsthat could damage system components.

R-12 Containers

Two basic, readily available containers are used tostore R-12 refrigerant: the 30 or 60 pound bulk canis-ters (Figure 9-2).

Always read the container label to verify the contentsare correct for the system being serviced. R-12 andR-134a refrigerants must not be mixed.

FIGURE 9-2. REFRIGERANT CONTAINERS

1. 30 Pound Cylinder 2. 60 Pound Cylinder


SERVICE TOOLS AND EQUIPMENT

RECOVERY/RECYCLE STATION

Whenever refrigerant must be removed from the sys-tem, a dual purpose station (Figure 9-3) performs bothrecovery and recycle procedures which follows thenew guidelines for handling used refrigerant. The re-covered refrigerant can then be recycled to reducecontaminants, and reused in the same machine or fleet.

NOTE: To be re-sold, the gas must be ‘‘re-claimed’’which leaves it as pure as new, but requires equipmentnormally too expensive for all but the largest refrigera-tion shops.

Equipment is also available to just remove or extractthe refrigerant. Extraction equipment does not cleanthe refrigerant. It is used to recover the refrigerant froman AC system prior to servicing.

To accomplish this, the recovery/recycle station sepa-rates the oil from the refrigerant and filters the refriger-ant multiple times to reduce moisture, acidity, andparticulate matter found in a used refrigerant.

Mixing different types of refrigerant will damageequipment. Dedicate one recovery/recycle stationto each type of refrigerant processing to avoidequipment damage.

Disposal of the gas removed requires laboratory ormanufacturing facilities.

Recycle equipment must meet certain standards aspublished by the Society of Automotive Engineers andcarry a UL approved label. The basic principals ofoperation remain the same for all machines, even if thedetails of operation differ somewhat.

LEAK DETECTOR

Two basic types of leak detectors are used on airconditioning systems today to locate suspected leaks.The propane, or halide type detector (Figure 9-4) usesa flame which changes colors (from pale blue - normalto purple/blue/violet for a large leak to light green/yel-low for a small leak) to successfully detect leaks.

The halide type consists of a hose for leak searching,a burner, tank, and a control valve. Safety is a vitalconcern with this type, as the fumes can be poisonous.Refer to WARNING on page M9-7.

FIGURE 9-3. RECYCLE/RECOVERY UNIT

FIGURE 9-4. HALIDE (PROPANE) LEAK DETECTOR

1. Burner2. Search Hose

3. Cylinder4. Shut-off Valve


One of the most common types is the electronic detec-tor (Figure 9-5) which tends to be safer and moreaccurate. It is a small hand-held device with a flexibleprobe used to seek leaks. A buzzer, alarm or light willannounce the presence of even the smallest leak.

Note that electronic leak detectors are available for useonly with R-12 or only with R-134a, while other modelsare suitable for use with either.

VACUUM PUMP

The vacuum pump is used to completely evacuate allrefrigerant, air, and moisture from the system by delib-erately lowering the pressure within the system to thepoint where water turns to a vapor (boils) and togetherwith all air and refrigerant is withdrawn (pumped) fromthe system. Normally the vacuum pump is only usedwhen a system has completely lost its charge of refrig-erant.

FIGURE 9-5. TYPICAL ELECTRONIC LEAKDETECTOR

FIGURE 9-6. TYPICAL VACUUM PUMP


SERVICE VALVES

Because an air conditioning system is a sealed system,two service valves are provided on the compressor toenable diagnostic tests, system charging or evacu-ation. Connecting the applicable hoses from the mani-fold gauge set to the compressor service valvesenables each of these to be readily performed.

Air conditioning systems designed for R-134a re-frigerant are equipped with a different type servicevalve designed to prevent accidental use of R-12in the system. Be certain the servicing equipmentis compatible with R-12 refrigerant.

Stem Type

Service valves may be one of two types. The stem typevalve (Figure 9-7) is capable of being placed in three

positions: front seat; intermediate (mid); and back seat.Each position represents a specific function desiredwhen testing the system.

Schrader Type

The Schrader type service valve (Figure 9-8), similar inappearance and function to the valve in a truck tire (therubber compound and spring pressures being quitedifferent) is becoming more common due to its capac-ity for easier accessibility. The Schrader valve can bemounted almost anywhere in the system. Two posi-tions are possible with this valve: Closed and Open,each serves a specific function during testing.

Protective caps are provided for each service valvewhen not being used for servicing purposes. Thesecaps must be kept on each valve to prevent contami-nation or damage to the valve core.

FIGURE 9-7. STEM TYPE SERVICE VALVE

FIGURE 9-8. SCHRADER TYPE SERVICE VALVE


MANIFOLD GAUGE SET

The manifold gauge set consists of a manifold with twoscrew-type hand valves, one for low side and one forthe high side of an air conditioning system, located ateach end of the manifold (Figure 9-9). Three fittings areprovided between these two valves. The first fittingconnects the low side hose to the suction side of thecompressor or the evaporator outlet. The second (cen-ter) fitting is provided to connect to the servicing can-ister to charge the system or for other serviceprocedures. The third fitting connects to the systemhigh side (discharge) hose leading from the compres-sor. Shut-off valves are required within 12 in. of the hoseends to minimize refrigerant loss.

Low Side Gauge

The Low Side Gauge, registers both vacuum and pres-sure. The vacuum side of the scale is calibrated from 0to 30 inches of mercury (in. Hg). The pressure side ofthe scale is calibrated to 150 psi, however, normalpressures seldom exceed 75 -- 80 psi.

Never open the hand valve to the high side atanytime when the air conditioning system is oper-ating. High side pressure, if allowed, may rupturecharging containers and potentially cause per-sonal injury.

High Side Gauge

The High Side Gauge is used to measure pressure onlyon the discharge side of the compressor. The scale iscalibrated from 0 to 500 psi, though normal pressuresare usually 300 psi or less.

Installing Manifold Gauge Set

Before attempting to service the air conditioning sys-tem, a visual inspection of both the engine and systemcomponents is recommended. Particular attentionshould be paid to the belts, hoses, tubing and allattaching hardware plus the radiator cap, fan clutch,and thermostat. Inspect both the condenser and theradiator for any obstructions or potential contamina-tion. Minimize all the possibilities for error or malfunc-tion of components in the air conditioning system.

Shut off engine. DO NOT attempt to connect serv-icing equipment when the engine is running.

1. Be sure all valves on the manifold are closed allthe way (turn them clockwise).

2. Check the hose connections on the manifold fortightness.

3. Locate the low and high side system servicefittings, clean and remove their protective caps.(See Figure 9-10)

4. Connect the two service hoses from the manifoldto the correct service valves on the compressor.(High side to compressor discharge valve and lowside to compressor suction side.)

The gauge hook-up process will be the same, regard-less of the gauge set being installed. Whether it is arecovery station or individual gauges, the connectionsare the same. The procedures performed next will varydepending on what type of equipment is being used. Ifa recovery/recycling station is being used, completeservicing can be accomplished. Using only a set ofgauges will limit the servicing to adding refrigerant orobserving pressures.

FIGURE 9-9. MANIFOLD GAUGE SET


Purging Air From Service Hoses

The purpose of this procedure is to remove all the airtrapped in the hoses prior to actual system testing.Environmental regulations require that all servicehoses have a shutoff valve within 12 in. of the serviceend. These valves are required to ensure only a minimalamount of refrigerant is lost to the atmosphere.

The initial purging is best accomplished when con-nected to recovery or recycle equipment. With thecenter hose connected to the recovery station, servicehoses connected to the high and low sides of thesystem, purging of the system can begin. (See Fig.9-11.)

The manifold valves should be closed. Activating thevacuum pump will now evacuate any air or moistureout of the center hose. This will require only a fewminutes of time as the hose is the only componentbeing placed in a vacuum. Closing the valve will theninsure the hose is purged. It is now safe to open theother manifold valves.

FIGURE 9-10. SERVICE HOSE HOOK-UP

FIGURE 9-11. PURGING SYSTEM


Adding Refrigerant to the System (without a charging station)

After determining that the system is low and additionalrefrigerant is required, perform the following:

1. Connect the center hose from the manifold gaugeset to the refrigerant dispensing valve on the con-tainer as shown in Figure 9-12.

2. Start the engine and set the idle at 1200 to 1500RPM and then turn on the air conditioning.

3. Open the refrigerant dispensing valve on the con-tainer and then the low pressure hand valve on themanifold. This will allow the refrigerant to enter thesystem as a gas on the low pressure or suctionside of the compressor. The compressor will pullrefrigerant into the system.

4. Continue adding refrigerant until the gauge readsin the normal range and/or the sight glass (ifequipped) is clear. The sight glass may not beclear for a moment just before or after the clutchcycles on and off, but should generally be clear.Gauge readings will fluctuate as the compressorcycles on and off.

Pressures within the air conditioning system varywith ambient temperature. A normal pressurerange is defined as follows:

Low side - 15 - 30 PSIHigh side - 150 - 280 PSI

5. When the gauges show a normal reading and/orthe sight glass (if equipped) is clear, close thehand valve on the refrigerant container.

FIGURE 9-12. TYPICAL CANISTER HOOKUP

1. Gauge Manifold2. Low side Hand Valve3. High Side Hand Valve

4. High Side Service Valve5. Low Side Service Valve6. Service Hose

7. Refrigerant Charging Container8. Shut-Off Valves9. Compressor


Stabilizing the AC System

Operating the system at full cooling capacity for a fewminutes after purging ensures that temperatures andpressures within the system will stabilize, allowing sys-tem testing.

During this stabilization period, do not open handvalves on manifold for any reason. Equipment dam-age and personal injury may result.

1. Leave test equipment attached to the system butensure it is clear of any moving components.

2. Start engine. Allow to operate approximately 1200- 1500 RPM.

3. Set air conditioning system to maximum coolingcapacity (blower at full speed, temperature settingat coldest point).

4. Open all truck windows and doors briefly to ex-haust any buildup heat in cab. Close windows anddoors.

5. Allow to operate in this manner for a minimum offive minutes. System should stabilize.

NOTE: If necessary, provide a fan in front of condensercoils large enough to develop air flow comparable tonormal ram air.

6. Place a thermometer in the air conditioning ventclosest to the evaporator. Wait five minutes toestablish that thermometer reflects temperatureinside cab, then check thermometer. At outsideambient temperature of 80° to 100° F, readingshould be between 38° and 45° F.

7. Check sight glass; bubbles may indicate systemis low on refrigerant.

NOTE: If low refrigerant is indicated by lower thannormal pressure readings and bubbles in sight glass,add refrigerant to enable adequate system testing

Adding Refrigerant and Stabilizing the System(with a recovery/recycling station)

When using a recovery/recycling station, the proce-dure is the same as previously described. The differ-ence is that instead of just opening the refrigerantcontainer, the refrigerant should be added 0.5 to 1pound at a time. After each instance of adding therefrigerant, pause long enough to observe the gaugereading and/or the sight glass (if equipped) to deter-mine if the system is full. Use the pressures listed onthe previous page.

Do not open high side hand valve. High side sys-tem pressure is greater than refrigerant container.Serious personal injury may result if the containerexplodes.Use hand valve to regulate low side reading duringcharging. DO NOT EXCEED 40 psi maximum. Exceeding this pressure may cause compressorfailure.

RECOVERING AND RECYCLING THEREFRIGERANT

Draining the Oil from the Previous Recovery Cycle

1. Place the power switch and the controller on therecovery unit in the OFF position.

2. Plug in the recovery station to the correct powersource.

3. Drain the recovered oil through the valve markedOIL DRAIN on the front of the machine.

4. Place the controller knob in the ON position. Thelow pressure gauge will show a rise.

5. Immediately switch to the OFF position and allowthe pressure to stabilize. If the pressure does notrise to between 5 psi and 10 psi, switch the con-troller ON and OFF again.

6. When the pressure reaches 5 to 10 psi open theOIL DRAIN valve, collect oil in an appropriatecontainer, and dispose of container as indicatedby local, state or Federal Regulation. THE OIL IS NOT REUSABLE, DUE TO CONTAMI-NANTS ABSORBED DURING ITS PREVIOUSUSE.


Performing the Recovery Cycle

1. Be certain the equipment being used is designedfor the refrigerant intended to be recovered.

2. Observe the sight glass oil level. Having drainedit, it should be zero.

3. Check the cylinder refrigerant level before begin-ning recovery to make sure you have enoughcapacity.

4. Confirm that all shut-off valves are closed beforeconnecting to the AC system.

5. Attach the appropriate hoses to the system beingrecovered.

6. Start the recovery process by operating the equip-ment as per the manufacturer’s instructions.

7. Continue extraction until a vacuum exists in the ACsystem.

8. If an abnormal amount of time elapses after thesystem reaches 0 psi and does not drop steadilyinto the vacuum range, close the manifold valvesand check the system pressure. If it rises to 0 psiand stops, there is a major leak.

9. Check the system pressure after the recoveryequipment stops. After five minutes, system pres-sure should not rise above ‘‘0’’ gauge pressure. Ifthe pressure continues to rise, restart and beginthe recovery sequence again. This cycle shouldcontinue until the system is void of refrigerant.

10. Check the sight glass oil level to determine theamount of oil that needs to be replaced. (Theamount of oil that was lost during the recoverycycle must be replaced back into the system).

11. Mark the cylinder with a ‘‘RECOVERED’’ (red)magnetic label to reduce the chance of charginga system with contaminated refrigerant. Keep arecord of the amount of refrigerant recovered, ifpossible.

Performing the Recycling Procedure

The recovered refrigerant contained in the cylindermust undergo the recycle procedure before it can bereused. The recycle or clean mode is a continuous loopdesign and cleans the refrigerant rapidly. Follow equip-ment manufacturer’s instructions for this procedure.

Evacuating and Charging the AC System

Evacuate the system once the air conditioner compo-nents are repaired or replacement parts are secured,and the AC system is reassembled. Evacuation re-moves air and moisture from the system. Then, the ACsystem is ready for the charging process, which addsnew refrigerant to the system.

Evacuating the System

1. Attach the high and low side hoses to the appro-priate connections.

2. Start the vacuum pump and run it for five minutes.

3. Check the gauge readings for five minutes. If thegauge needle moves up, the system is not sealed.The vacuum that was just created did not hold, airand moisture are being sucked into the system bythat same vacuum.

4. Tighten any loose connections. Re-start the pump,and open the hand valves on the gauges again.Repeat the vacuum test.

5. If the leak has been repaired, run the vacuumpump for at least an hour to remove any moisturefrom the system.

The moisture must turn to gas before the pump can pullit out. The moisture takes time to boil away, so that itcan be drawn out of the system. The vacuum pump candraw most of the air out quickly, but a deep vacuumrequires more time; the deeper the vacuum, the moretime required.

Charging the AC System

When adding a full charge of refrigerant, it is possibleto put it in as a gas or as a liquid. Adding refrigerant asa liquid is faster but can damage the compressor if notdone correctly. The procedure used, and where therefrigerant is added in the AC system makes a differ-ence. When using refrigerant as a liquid, never addmore than two thirds of system requirements as aliquid. Finish charging the system using gas.


SYSTEM PERFORMANCE TEST

This test is performed to establish the condition of allcomponents in the system. Observe these conditionsduring testing:

1. Start engine and operate at 1200 - 1500 RPM.

2. Place fan in front of condenser to simulate normalram air flow and allow system to stabilize.

3. Place a thermometer in air conditioning vent clos-est to evaporator.

4. Evaluate the readings obtained from the gaugesagainst those in Figure 9-19. In addition, consulteach applicable ‘‘diagnosis’’ situation in this sec-tion.

As preliminary steps to begin checkout of the system,perform the following:

1. Close all windows and doors in the cab.

2. Set air conditioning system at maximum coolingand blower to high speed operation.

3. Read indication on the two manifold gauges.Readings should be within normal range, ad-justed for current ambient temperature.

4. Observe sight glass. It should be clear of bubbles.

5. Compare evaporator discharge air temperaturereading against specifications shown in Figure9-19.

6. Carefully feel the hoses and components on thehigh side. All should be warm-hot to the touch.Check the inlet and outlet of receiver-drier for eventemperatures, if outlet is cooler than inlet, a re-striction is indicated.

7. Feel the hoses and components on the low side.They should be cool to the touch. Check connec-tions near the expansion valve, inlet side shouldbe warm and cold-cool on the outlet side.

8. Check the operation of the temperature controlswitch to ensure the compressor drive clutchengages and disengages. A 5°-- 10° F evaporatorair temperature rise between the cut-off and cut-inpoints of control switch is not uncommon.

9. If these conditions are met, the system is consid-ered normal. Shut down engine. Backseat servicevalves, if used. Remove gauges and install thecaps on the service valves.

10. If conditions are not met, refer to ‘‘Diagnosis’’section.

SYSTEM LEAK TESTING

Refrigerant leaks are probably the most commoncause of air conditioning problems, resulting in inade-quate or no cooling, to major internal component dam-age. Leaks most commonly develop in two or threeplaces. The first is around the compressor shaft seal,often accompanied by an indication of fresh refrigerantoil. If a system is not operated for a while (wintermonths), the shaft seal may dry out and leak slightly.The centrifugal force of the clutch pulley spinning canalso cause the problem. When the system is operatedand lubricant wets the seal, the leak may stop. Suchleaks can often be located visually, or by feeling withyour fingers around the shaft for traces of oil. (The R-12itself is invisible, odorless, and leaves no trace when itleaks, but has a great affinity for refrigerant oil.)

A second common place for leaks is the nylon orrubber hoses where they are crimped or clamped tothe fittings, or where routing allows abrasion. Otherthreaded joints or areas where gaskets are used shouldbe visually and physically examined. Moving your fin-gers along the bottom of the condenser and evapora-tor, particularly near the drain hole for the condensatewill quickly indicate the condition of the evaporator.Any trace of fresh oil here is a clear indication of a leak.

To locate a leak, four common types of leak detectorsare used. Usually, a 50% charged system is enough tofind most leaks. If the system is empty, connect themanifold gauge set to the system and charge at leastone (1) lb. of refrigerant into the system.

Use extreme caution leak testing a system whilethe engine is running. Stay clear of all movingcomponents, and don’t allow high side pressure toexceed 300 psi.

In its natural state, R-12 refrigerant is a harmless,colorless gas, but when combined with an openflame, it will generate toxic fumes (phosgene gas),which can cause serious injuries or death. Whenusing a halide torch for detecting air conditioningsystem leaks, always insure that the area is ade-quately ventilated. Do not breathe fumes from thetorch and keep flames away from flammable mate-rial.

NOTE: R-12 refrigerant is heavier than air and willmove downward when it leaks. Apply pickup hose ortest probe on the undersurface of all components tolocate leak.


Electronic leak detector

(Refer to Figure 9-5). As the test probe is moved intoan area where traces of R-12 are present, a visual oraudible announcement indicates a leak. Audible unitsusually change tone or speed as intensity changes.

Halide (propane) Torch

1. Light the torch (Figure 9-4) by opening the pro-pane can and igniting the flame; carefully adjustthe flame to a height sufficient to heat the reactionplate to a cherry red color.

2. As plate turns red, adjust flame to a height slightlyabove the plate and high enough to sustain thecherry red color.

Too high a flame will overheat and destroy thereaction plate.

3. Slowly and carefully move the pickup hose aroundthe various components of the system. Don’t rushtesting as R-12 must travel length of hose to reachflame.

4. Observe the flame for any noticeable change incolor.

Tracer dyes

Tracer dyes are available that can be added to thesystem as R-12 is added. The system is then operatedto thoroughly circulate the dye. As R-12 escapes, itleaves a trace of the dye at the point of leakage, whichis then detected using an ultraviolet light, revealing abright fluorescent glow.

Soap and water

Soap and water can be mixed together and applied tosystem components. Bubbles will appear to pinpointthe specific location of leaks.

After determining the location or source of leak(s),repair or replace leaking component(s).

Engine must not be running during this procedure.Supply adequate ventilation and extinguish anynearby flame sources.

FLUSHING AIR CONDITIONER COMPONENTS

The flushing process is used to remove contaminantsfrom hoses, lines and some of the other system com-ponents. DO NOT flush the compressor, expansionvalve or metering device or screens. These are benchchecked, cleaned and repaired or replaced. A receiver-drier, accumulator, expansion valve and tube are neverflushed, they are replaced. When you disassemble andflush components and hoses (lines), it is best to RE-VERSE FLUSH. Flush in the opposite direction of R-12flow. Flush the system using R-11 or R-13 or othercommercial solvent sold for that purpose. Figure 9-13illustrates the use of a flushing kit.

Always wear protective goggles and provide ade-quate ventilation when flushing components.Never use R-12 as a flushing agent.

When opening the AC system, plug any open linesexcept when flushing. Fill the cylinder of the flushinggun with solvent. Insert the rubber gun probe into theoutlet of each component and dispense solvent (re-verse flush). Unless there is a serious blockage, thesolvent will appear at the other end of the components.Flush the next component in turn until all parts areflushed.

FIGURE 9-13. FLUSHING COMPONENTS


Allow solvent to evaporate completely (about 30 min-utes) and then assemble the system replacing partswhere necessary.

NOTE: The length of the hose will affect the refrigerantcapacity. When replacing hoses, always use the samehose length, if possible. Always replace the receiver-drier when assembling the AC system after flushing.

Before system assembly, check the compressor oillevel and fill to manufacturer specifications.

SYSTEM REPAIRThe following service and repair procedures are notany different than typical vehicle service work. How-ever, AC system components are made of soft metals(copper, aluminum, brass, etc.). Comments and tipsthat follow will make the job easier and reduce unnec-essary component replacement.

All of the service procedures described are onlyperformed after the system has been discharged.Never use regular shop oil or joint compound tolubricate or seal any AC connections.

NOTE: To help prevent air, moisture or debris fromentering an open system, cap or plug open lines,fittings or components as soon as they are discon-nected. Keep all connections clean (also caps andplugs used) so debris can’t enter accidentally. As ageneral rule, replace any gaskets and O-rings with newones. Use fresh refrigeration oil to lubricate connec-tions, gaskets and O-rings.

Hoses and Fittings

When replacing hoses, be sure to use the same typeand ID hose you removed. After lubricating the hoseand fitting, slide the hose over the fitting. The hoseclamp should be on the hose before it is pushed ontothe fitting and seated. The hose should be fully seatedor pushed in to a locating bead if present. When hosesor fittings are shielded or clamped to prevent vibrationdamage, be sure these are in position or secured.

Lines

Always use two wrenches when disconnecting or con-necting AC fittings attached to metal lines. You areworking with copper and aluminum tubing which cankink or break easily. Tube O-ring type fittings requireonly 18 ft. lbs. (24.4 N.m) of torque for correct sealing.When grommets or clamps are used to prevent linevibration, be certain these are in place and secured.

Expansion Valve

When removing the expansion valve from the system,remove the insulation, clean the area and disconnectthe line from the receiver-drier. Detach the capillary(bulb) and external equalizer tube (if present) from their


mounting locations. Remove the expansion valve fromthe evaporator inlet. Expansion valve service is limitedto cleaning or replacing the filter screen. If this is notthe problem, replace the valve. Secure the capillaryand equalizer, if used, to clean surfaces and replace orattach any insulating material.

Receiver-Drier

The receiver-drier can not be serviced or repaired. Itshould be replaced whenever the system is opened forany service. If the receiver-drier has a pressure switchto control the clutch, it should be removed and installedon the new unit.

Thermostat

A thermostat can be stuck open or closed due tocontact point wear or fusion. The thermostat tempera-ture sensing element (capillary tube) may be broken orkinked closed and therefore unable to sense evapora-tor temperature.

When thermostat contact points are stuck open or thesensing element can not sense temperature in theevaporator, the clutch will not engage (no AC systemoperation). Causes are a loss of charge in the capillarytube or a kink, burned thermostat contact or just nocontact. A quick method of troubleshooting is to by-pass the thermostat by hot wiring the clutch coil with afused lead. If the clutch engages, replace the thermo-stat.

Thermostat contact points may be fused (burned)closed and the clutch will not disengage. Causes are afaulty switch that could be due to fatigue. The thermo-stat must be replaced. When the clutch will not disen-gage you may also note that condensate has frozen onthe evaporator fins and blocked air flow. There will alsobe below normal pressure on the low side of thesystem.

Side effects can be compressor damage caused by oilaccumulation (refrigeration oil tends to accumulate atthe coolest spot inside the system) and lower thannormal suction pressure that can starve the compres-sor of oil.

Clutch

Clutch problems include electrical failure in the clutchcoil or lead wire, clutch pulley bearing failure, worn orwarped clutch plate or loss of clutch plate spring tem-per. Defective clutch assembly parts may be replacedor the whole assembly replaced. If the clutch showsobvious signs of excessive heat damage, replace thewhole assembly.

The fast way to check electrical failure in the lead wireor clutch coil is to hot wire the coil with a fused lead.This procedure bypasses clutch circuit control de-vices.

Clutch pulley bearing failure is indicated by bearingnoise when the AC system is off or the clutch is notengaged. Premature bearing failure may be caused bypoor alignment of the clutch and clutch drive pulley.Sometimes it may be necessary to use shims or en-large the slots in the compressor mounting bracket toachieve proper alignment.

Excessive clutch plate wear is caused by the platerubbing on the clutch pulley when the clutch is notengaged or the clutch plate slipping when the clutchcoil is energized. A gap that is too small or too largebetween the plate and clutch pulley or a loss of clutchplate spring temper are possible causes. The ideal gapbetween the clutch pulley and the clutch plate is 0.030to 0.040 in., with 0.060 in. maximum. If the gap is toowide, the magnetic field created when the clutch coil isenergized will not be strong enough to pull and lockthe clutch plate to the clutch pulley.

Compressor

The compressor can fail due to shaft seal leaks (noR-12 in the system), defective valve plates, bearings,other internal parts or problems associated with highor low pressure, heat or lack of lubrication. Be sure thecompressor is securely mounted and the clutch pulleyis properly aligned with the drive pulley.

You may use a mechanics stethoscope to listen fornoises inside the compressor, loose wrist pins, pistonslap, noisy valves or bearings. Feel the compressorbody and note if the lower part of the crankcase isextremely hot. This indicates the compressor is low onor may be starved for oil. Compressor lockup is anindication of a broken piston or connecting rod.


CHECKING COMPRESSOR OIL LEVEL

Every air conditioning system and compressor de-pends on refrigeration oil for lubrication and safe op-eration.

Refrigerant oil, under normal circumstances inside thesealed system, cannot go anywhere, and there is noneed to check the oil at such times. It is a highly refined,pure mineral oil, containing no additives, waxfree andcontained in a dehydrated form. For this reason, al-ways keep a cap on an oil container except when inuse. Moisture is quickly absorbed by the oil.

Whenever a system is opened for service, the com-pressor oil level should be checked and clean refrig-eration oil added as required by the manufacturer’sspecifications (usually located on compressor).

York Compressor Oil Level Check (2 cylinder model).

NOTE: The York compressor need not be removedfrom the system to be checked. If system has beendischarged, steps 1 through 3 will not apply.

1. Run compressor for 10 to 15 minutes to allow oilto thoroughly circulate through the system. Stopengine.

2. Connect manifold gage set to compressor servicevalves.

3. Refer to ‘‘Performing the Recovery Cycle’’.

4. Unscrew oil check plug five full turns to bleed offremaining pressure until gauge reads 0.

NOTE: Suction pressure may rise slowly to 5 psi gaugepressure after both valves are closed.

5. Remove oil check plug and O-ring to check oillevel with dipstick. (See Figure 9-14 for details andFigure 9-15 for location.)

6. Check the findings against the values in the tablein Figure 9-14.

7. If necessary to add oil, add only the type specifiedby the system manufacturer (never more than 10ounces).

8. Slip the O-ring over the oil fill plug threads, beingcareful not to twist the O-ring. Insert oil plug in oilfiller opening and snug-tighten.

OIL CHARGE VS. DIP STICK DEPTHOIL

CHARGEOunces 6 8 10 12 16

HorizontalMount 13/16" 1" 1-3/16" 1-5/8" 1-15/16"

VerticalMount 7/8" 1" 1-1/8" 1-7/16" 1-7/8"

FIGURE 9-14. DIPSTICK DIMENSIONS & DETAILS(2 Cylinder York)

FIGURE 9-15. OIL LEVEL CHECK(York Compressor)


Sanden Compressor Oil Level Check (5-Cylinder)

NOTE: This check can be better performed with thecompressor out of the system and on the bench. Ifsystem has been discharged, steps 1 and 2 will notapply.

1. Run compressor for 10 minutes to allow oil tothoroughly circulate through the system.

2. Stop engine; recover refrigerant.

3. Remove compressor from the system by loosen-ing mounting bolts and removing drive belt. Placecompressor on bench with oil fill plug at top deadcenter.

4. Using an angle gage, determine the mountingangle across the two mounting ears flat surfaces.After centering the bubble on the gage, check theangle of mounting to the closest degree.

5. Remove oil filler plug slowly to release pressure.Using figure 9-16 as a guide, peer through oil fillerhole to rotate the clutch front plate to place inter-nal parts of compressor as shown in illustration.

6. If the compressor is right-mounted (facing clutch)(See Figure 9-17), position the parts as thoughthey were moving toward the rear of the compres-sor (equal to the discharge stroke of piston).

7. If the compressor is left-mounted (facing theclutch) (See Figure 9-17), position the parts asthough they were moving to the front of the com-pressor (equal to the suction stroke of piston).

NOTE: Either step will clear the path of internal partsso as to allow dipstick insertion to its full depth.

8. Insert dipstick (Sanden p/n 32447) through oil fillerhole until stop point is reached. (See Figure 9-17).Use the following as a guide to determining thecorrect angle of the dipstick for each type ofmounting (right or left):

If mounting angle is to the RIGHT, point of angleshould be to LEFT.

If mounting angle is to the LEFT, point of angleshould be to RIGHT.

In both, bottom surface of angle must be flushwith surface of oil filler hole.

9. Remove the dipstick and count the increments ofoil (numbers on dipstick). (Refer to Figure 9-18 forcorrect mounting angle/oil level determination.)

10. Add or subtract oil to reach a mid-range of valueif the actual reading is not exactly on the dipstickincrement.

Exercise care not to overtighten plug to stop a leakin step 11. Remove plug instead and install newO-ring.

11. Insert the oil filler plug, checking that O-ring is nottwisted. Torque the plug to 6 to 9 ft. lbs. (8 - 12N.m).

FIGURE 9-16. LOCATING INTERNAL PARTS

FIGURE 9-17. MOUNTING ANGLE FOR DIPSTICKINSERTION


EVACUATING THE SYSTEMEvacuating the complete air conditioning system isrequired in all new system installation. Also, whenrepairs are made on systems requiring a componentreplacement (system opened) or a major loss of refrig-erant has occurred. All will require that a vacuum bepulled using a vacuum pump that completely removesany moisture from the system. Once properly evacu-ated, the system can be recharged with refrigerantagain.

Using a pump to create a vacuum in the air condition-ing system effectively vaporizes any moisture, allowingthe water vapor to be easily drawn out by the pump.The pump does this by reducing the point at whichwater boils (212°F at sea level with 14.7 psi). In avacuum, water will boil at a lower temperature depend-ing upon how much of a vacuum is created.

As an example, if the ambient air outside the truck is75°F at sea level, by creating a vacuum in the systemso that the pressure in inches of mercury is below thatof the outside air (in this case, at least 29.5 inches ofvacuum is needed), the boiling point of water will belowered to 72°F. Thus any moisture in the system willvaporize and be drawn out by the pump if the pump isrun for approximately an hour. The following stepsindicate the proper procedure for evacuating all mois-ture from the heavy duty air conditioning systems.

Do not use the air conditioning compressor as avacuum pump or the compressor will be damaged.

NOTE: Lower the vacuum requirement one inch forevery 1000 feet above sea level at your location.

1. With the manifold gauge set still connected (afterdischarging the system), connect the center hoseto the inlet fitting of the vacuum pump as shownin Figure 9-19. Then open the low side hand valvesto maximum.

2. Open the discharge valve on the vacuum pump orremove the dust cap from the discharge outlet.Turn the pump on and watch the low side gauge.The pump should pull the system into a vacuum(if not, the system has a leak).

3. Run the pump for five minutes, close the handvalves and shut off the pump.

MOUNTINGANGLE

(Degree)

ACCEPTABLE OIL LEVEL IN INCREMENTS

Model 505010203040506090

4-66-88-1010-1111-1212-1312-1315-18

3-55-76-87-98-108-109-119-11

4-66-87-98-109-119-119-119-12

2-44-55-66-77-99-1010-1212-13

507 508 510

FIGURE 9-18. MOUNTING ANGLE/OIL LEVELDETERMINATION

FIGURE 9-19. VACUUM PUMP HOOKUP

1. Low Pressure Hand Valve 2. High Pressure Hand Valve

3. Vacuum Pump


4. Observe gauge reading and wait 10 minutes.Reading should not vary more than 1-2 in. hg.After waiting, if more vacuum is lost than this, aserious leak is indicated and the system must berecharged, leak tested, repaired and evacuated.

5. Turn on pump, open hand valves and continueevacuation for at least one hour.

NOTE: If system has excessive amounts of moisture,60 minutes evacuation may not be sufficient since thewater must turn to a vapor to be drawn out of thesystem. If a sealed system is known to be, and gaugereadings increase after 1 hour, extend the evacuationtime to ensure total moisture removal.

6. Close the manifold hand valves and turn off vac-uum pump, watching the low side gauge reading.If vacuum remains for a few minutes, the systemis ready for charging.


TROUBLESHOOTING PRE-DIAGNOSIS CHECKS

A lot of time and frustration can be saved if obviouscauses of system problems are checked before con-necting the manifold gauge set. If the system indicatesInsufficient cooling or no cooling, the following pointsshould be checked before proceeding with the systemdiagnosis procedures.

PREPARING FOR DIAGNOSIS

Successfully servicing an air conditioning system, be-yond the basic procedures outlined in the previoussection, requires additional knowledge of system test-ing and diagnosis.

A good working knowledge of the manifold gauge setis required to correctly test and diagnose an air condi-tioning system. An accurate testing sequence is usuallythe quickest way to diagnose an internal problem.When correctly done, diagnosis becomes an accurateprocedure rather than guesswork.

Compressor Belt - Must be tight, and properlyaligned.

Compressor Clutch - The clutch must engage. Ifit does not, check fuses, wiring, and switches.

Oil Leaks - Inspect all connection or componentsfor refrigeration oil leaks (especially in the areaof the compressor shaft). A leak indicates anR-12 refrigerant leak.

Electrical Check - Check all wires and connec-tions for possible open circuits or shorts. Checkall system fuses.

Note: Some systems use different safety devices in thecompressor circuit to protect the compressor. Checkthe thermal fuse, the low pressure cutout switch, highpressure cutout switch or trinary pressure switch ifequipped.

Cooling System - Check for correct cooling sys-tem operation. Inspect the radiator hoses, heaterhoses, clamps, belts, water pump, thermostatand the radiator for condition or proper opera-tion.

Radiator Shutters - Inspect for correct operationand controls, if equipped.

Fan and Shroud - Check for proper operation offan clutch. Check installation of fan and shroud.

Heater/Water Valve - Check for malfunction orleaking.

System Ducts and Doors - Check the ducts anddoors for proper function.

Refrigerant Charge - Make sure system is prop-erly charged with the correct amount of refriger-ant.

PRELIMINARY STEPS

The following steps outline the correct proceduresnecessary to prepare the truck and the system fortesting and diagnosis:

1. Correctly connect the manifold gauge set to thesystem. Refer to the connection and purging pro-cedures outlined in this section.

2. Run the engine with the air conditioning system onfor five to ten minutes to stabilize the system.

3. With the engine and the system at normal operat-ing temperature, conduct a Performance Test asoutlined in this section.

DIAGNOSIS OF GAUGE READINGS & SYSTEMPERFORMANCE

The following Troubleshooting Chart lists typical mal-functions encountered in air conditioning systems. In-dications and or problems may differ from one systemto the next. Read all applicable situations, service pro-cedures, and explanations to gain a full understandingof the system malfunction. Refer to ‘‘Suggested Cor-rective Action’’ for suggested service procedures.


TROUBLESHOOTING CHARTPossible Causes Suggested Corrective Action

TROUBLE: Insufficient Cooling

Indications: Low side pressure LOWHigh Side Pressure LOWDischarge air is only slightly coolBubbles observed in sight glass

Low R-12 charge, causing pressures to be slightlylower than normal.

Check for leaks by performing leak test.

No Leaks Found:1. Charge System

2. Performance Test System

Leaks Found:1. Discharge R-12 from system.

2. Repair leaks as necessary.

3. Check and replace any compressor oil lost dueto leakage.

4. Evacuate System

5. Charge System

6. Performance Test System

TROUBLE: Little or No Cooling

Indications: Low side pressure VERY LOWHigh side pressure VERY LOWDischarge Air WarmNo bubbles observed in sight glass, May show oil streaks.

R-12 sensing pressure switch may have compressorstopped.

R-12 Refrigerant excessively low; leak in system.

1. Add Refrigerant (make sure system has at least50% of its normal amount) and leak test system.

2. It may be necessary to use a jumper wire to en-able the compressor to operate if it has shutdown due to pressure sensing switch.

3. Discharge system, and repair leak.

4. Check and replace any compressor oil lost dueto leakage.

5. Evacuate System

6. Charge System

7. Performance test system.


TROUBLE: Insufficient or No Cooling

Indications:Low side pressure TOO HIGHHigh side pressure TOO HIGHDischarge air not coolOccasional bubbles appear in sight glass

Air and/or moisture in system

Large amounts of air will indicate higher gauge read-ings since the air is non-condensable under thesepressures. Hot gas (air) enters the evaporator, takingspace of R-12, causing temperature and pressure toincrease.

NOTE: Excessive moisture may be indicated with nor-mal gauge readings and then low side dropping into avacuum and high side lowering also. This usually oc-curs during the hottest part of a hot day when systemdemand is increased. R-12 freezes at the expansionvalve, blocking R-12, compressor evacuates low side,into high side. Since R-12 can’t flow past expansionvalve, it super cools in condenser causing tempera-tures and pressures to decrease on the high side.

1. Since system is saturated with air/moisture, Dis-charge R-12

2. Replace receiver-drier (desiccant)

3. Change refrigerant oil

4. Flush system components

5. Evacuate system thoroughly

6. Charge system

7. Performance test system

TROUBLE: Insufficient or No Cooling

Indications: Low side pressure HIGHHigh side pressure NORMAL TO HIGHDischarge air is warmSuction hose shows heavy sweating(considerable moisture)

Expansion Valve Malfunction (stuck open)

Expansion valve isn’t providing the restriction neededfor a proper pressure drop, R-12 flow is excessive andcondenser cannot remove enough B.T.U.’s causinghigher pressures and temperatures.

1. Operate system and spray liquid R-12 onto thecapillary tube (thermal bulb) or the head of theexpansion valve. Low side should drop into avacuum, indicating valve is all right. Clean sur-faces of thermal bulb and contact area, securein place and install insulating material.

2. If low side does not drop into a vacuum whenvalve is cooled, discharge system and replaceexpansion valve.

3. Evacuate System

4. Charge System



TROUBLE: Insufficient Cooling

Indications: Low side pressure TOO LOW (VACUUM)High side pressure NORMAL TOO LOWDischarge air only slightly coolExpansion valve outlet frosty or sweaty

Expansion valve malfunction (stuck closed)

Restriction near expansion valve (valve itself, inlet oroutlet screen clogged) or lost charge in thermal bulbcausing compressor to evacuate low side, R-12 supercools in condenser because of restricted flow, loweringtemperature and pressure.

1. Operate system and warm up expansion valve &thermal bulb area (hair dryer or with hand). Lowside pressure should increase, indicating valveis all right. Clean surfaces, secure in place andinsulate.

2. If no change is observed, discharge system andreplace expansion valve.

3. Evacuate system

4. Charge system



AMBIENTTEMPERATURE

(°F)

MANIFOLD GAUGE READING (PSI) EVAPORATOROUTLET TEMP.

(°F)Low Side High Side

60 0--4 95--11565 4--8 105--12570 8--12 115--135

35--55

75 12--14 130--15080 12--18 150--17085 16--20 165--18590 18--22 175--19595 22--24 185--205100 24--27 210--230105 25--29 230--250110 26--32 250--270115 30--36 265--285120 32--42 285--310

FIGURE 9-20. TEMPERATURE/PRESSURE RELATIONSHIP

NOTE: The pressures shown in this table are representative. They will vary depending uponsystem configuration, components and operating conditions. Evaporator outlet tempera-tures will vary depending upon thermometer placement location, blower fan speed andsystem conditions.


AUTOMATIC POSITIVE LOCKING DIFFERENTIAL

The automatic positive locking differential is anOption which may be installed when truck is originallymanufactured or may be installed in the truck to re-place the standard HAULPAK® differential.

Installation Of Locking Differential To ReplaceThe Standard HAULPAK® Differential

1. Refer to Section "G" for Differential Carrier Assem-bly Removal, Differential Cage Removal, and Dif-ferential Cage Disassembly.

2. Remove all roll pins from differential cage.

3. None of the internal parts of the HAULPAK®

differential cage will be used at assembly.

4. Install complete locking differential (3, Figure 12-1)with retainer (1). Install differential cage cap (4),tighten capscrews (2) to standard torque andsafety wire.

5. Be sure to remove retainer (1) before differentialcarrier assembly is installed in final drive case.

6. Refer to Section "G" for Differential Assembly toCarrier, Backlash Adjustment Bearing, BearingPreload and Installation into Final Drive Case.

Locking Differential Disassembly

The positive locking differential contains com-pressed springs. Install retainer (1, Figure 12-1)before separating differential cage. Place differen-tial assembly in press and maintain pressure onassembly as retainer is removed. Carefully releasepress until springs are no longer compressed.Failure to observe this warning can cause personalinjury.

1. Refer to Section "G" for Differential Carrier Assem-bly Removal, Differential Cage Removal, and Dif-ferential Cage Disassembly.

2. Install retainer (1, Figure 12-1) before removingdifferential cage cap (4).

3. After locking differential has spring pressure re-leased, inspect all parts for chipped splines andteeth. If splines or teeth are chipped, replace.

4. Check spring rate. At a length of 1.43 in. (36.3 mm),the load should be 220 ± 22 lbs. (99.8 ± 9.9 kg).

FIGURE 12-1. LOCKING DIFFERENTIAL

1. Retainer 3. Locking Differential2. Capscrews 4. Differential Cage Cap

M12001 Automatic Positive Locking Differential M12-1

Automatic Locking Differential Assembly

1. Be sure all parts are clean.

2. Assemble components to allow for compressionof springs (2, Figure 12-2) and installation of re-tainer (1, Figure 12-3).

3. Place one spring (2, Figure 12-2) over hub of sidegear (1). Be sure spring is fully seated on sidegear.

4. Install cup end of spring retainer (3) on spring.

5. Place driving clutch (4) on spring retainer withteeth pointing away from spring.

6. Be sure that these components freely engage asdriven clutch is pushed against spring and splinesengage side gear splines.

7. Install spider and center cam (5) on driven clutch.Check that long tooth on spider indexes slot inhold out ring of driven clutch and lugs of hold outring engage slots in center cam.

8. Install second driven clutch (4), spring retainer (3),spring and side gear.

9. Compress assembly and install retainer (1, Figure12-3).

Locking Differential Installation in Cage

The locking differential can be assembled as a unit withretainer installed and placed in differential cage, or theindividual components can be installed in differentialcage and assembly compressed for installation of cageretaining capscrews.

1. Place locking differential in ring gear end of differ-ential cage.

2. Install differential cage cap (4, Figure 12-3) andretaining capscrews (2). Tighten to standardtorque and safety wire.

Be sure to remove retainer (1) before installingdifferential cage in carrier.

3. Refer to Section "G" for Differential Assembly In-stallation to Carrier, Backlash Adjustment BearingPreload and Installation Into Final Drive Case.

FIGURE 12-2. LOCKING DIFFERENTIAL ASSEMBLY

1. Side Gear 4. Drive Clutch2. Spring 5. Spider and Center Cam3. Spring Retainer

FIGURE 12-3. LOCKING DIFFERENTIAL

1. Retainer 3. Locking Differential2. Capscrews 4. Differential Cage Cap

M12-2 Automatic Positive Locking Differential M12001

RADIATOR SHUTTERS

TEMPERATURE CONTROL CIRCUITThe temperature control system contains a solenoidvalve, temperature switch and relay, shutter controlcylinder, radiator shutter assembly and the necessaryhoses and wiring for operation.

OPERATIONHydraulic pressure to operate the shutters is suppliedfrom a pilot port on the auxiliary manifold and directedto the solenoid valve located on the right side of theradiator top tank.

On engine start up, the solenoid valve will be in itsnormally open position, allowing oil pressure to beapplied to the shutter control cylinder to move theshutters to a fully closed position. This blocks air flowthrough the radiator to speed the warm up of coolantthrough the system.

The 24 volt unswitched side of the engine oil pressureswitch supplies 24 volts to the solenoid switch.

As the system coolant temperature approaches normaloperating levels, the temperature switch on the enginethermostat housing will, at approximately 185oF(85oC), close and provide a ground for the solenoidvalve. The solenoid valve will then shift and redirectpressure oil to the cylinder, opening the shutters.

To maintain proper pressures in the air conditioningsystem, an over ride circuit to open the shutters isprovided by using the trinary switch located on thereceiver-dryer. When refrigerant pressure at the re-ceiver-dryer reaches approximately 200-230 psi (1.38-1.59 MPa), twenty-four volts from the engine oilpressure switch will be allowed through the trinaryswitch to the coil side of the relay. The relay (locatedon the top side of the radiator shroud), will close thenormally open contacts and provide a ground for theshutter solenoid valve. The solenoid valve will then shiftand redirect pressure oil to the cylinder, opening theshutters.

M19001 Radiator Shutters M19-1

NOTES:

M19-2 Radiator Shutters M19001

SECTION N

OPERATOR’S CAB

INDEX

TRUCK CAB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N2-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N2-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N2-4

OPERATOR COMFORT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-1OPERATOR SEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-1

Adjustment Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-1Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-1Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-1Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-2Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-2Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-2

HEATER/AIR CONDITIONER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-4Water Control Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-4Heater/Air Conditioner

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-4Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-6Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-7Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-7Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N4-7

OPERATOR CONTROLS AND INSTRUMENT PANEL . . . . . . . . . . . . . . . . . . . N5-1OPERATOR CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-1INSTRUMENT PANEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-4

Retarder Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-8INSTRUMENT PANEL (Right Side) . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-9HEATER/AIR CONDITIONER CONTROLS . . . . . . . . . . . . . . . . . . . . . . N5-12THROTTLE CONTROL PEDAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-13

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-13Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-13Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-14Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-15Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N5-15

N01009 3/90 Index N1-1

NOTES

N1-2 Index N01009 3/90

TRUCK CABRemoval

1. Raise the truck body and install the body-upretaining pin (1, Figure 2-1) to secure body in thefully raised position.


3. Insure key switch has been ‘‘Off’’ for at least 90seconds to allow steering accumulator oil to drainback to tank. Check by turning steering wheel.

4. Bleed the pressure from the brake accumulatorsby turning the bleeder valves located on the LowBrake Pressure Detection Module counterclock-wise. When the accumulators are completely bleddown, close bleeder valves by turning the bleedervalve handles clockwise. Do not leave valvesopen.

Make certain the steering and brake accumulatorsare completely bled down before any componentsare disconnected. Rotate the steering wheel, nomovement should occur.

NOTE: The hydraulic hoses on the steering controlvalve and the brake manifold do not need to be discon-nected to remove the cab. The steering control valveand brake manifold can be removed as assemblieswith hoses attached. If necessary to remove thesecomponents from the truck for repairs etc., mark allhoses prior to removal and cap all openings to preventcontamination.

5. Disconnect battery cables using the followingsequence:

a. Turn the ATEC power switch ‘‘Off’’.

b. Remove the battery positive (+) cable.

c. Remove the battery negative (-) cable.

NOTE: Identify all electrical connection points andwires before disconnecting.

6. Disconnect required transmission and engine cir-cuit wiring inside the cab and pull wires throughrouting holes from under the rear portion of thecab, near the horse collar. Make certain all wiringis disconnected and retaining devices removed.

7. Disconnect the four cannon plugs and any othersingle harness connectors from under the frontpart of the cab bottom. A ‘‘T’’ connection is pro-vided underneath the cab for disconnecting thepower cable leading to the instrument panel.

8. Remove all retaining clamps securing hoses andwiring to the cab.

9. Protect the ends of the electrical cables and wiresfrom damage and contamination and securethem to prevent interference with the cab re-moval.


1. Body-up Retaining Pin2. Body

3. Body Pivot Pin4. Frame

N02006 4/92 Truck Cab N2-1

10. Remove capscrews at flange (3, Figure 2-2). Re-move nuts (6), washers (7 & 8) and capscrew (9)at each rubber bushing. Lower the valve assemblyfrom the mount and support assembly to preventdamage to hoses if still attached.

NOTE: If the steering control valve is to be removedfor repairs, refer to ‘‘Hydraulic System, Section "L",Steering Control Valve.’’

11. Tag and remove hoses from the retarder treadlevalve. Cap openings to prevent contamination.

12. Remove capscrews securing brake manifold andtreadle valve to the cab floor.

13. Lower the brake manifold, treadle valve and hosesaway from the cab floor and support assembly toprevent damage to hoses if still attached.

NOTE: If repairs are required on the assembly, referto ‘‘Brake Circuit Component Service’’, Section "J".

14. Disconnect the cable from throttle control by re-moving the clevis pin and cable anchor. Securecable out of the way.

15. Remove capscrews retaining the section of hoodnearest the right side of the cab and set the hoodsection aside.

Do not disconnect any heater or air conditioninghoses from assembly for removal of cab.


1. Universal Joint2. Stub Shaft3. Flange & Isolator4. Steering Valve Column5. Mounting Plate6. Nut

7. Lockwasher 8. Flatwasher 9. Capscrew10. Steering Control

Valve11. Valve Mounting

Plate

FIGURE 2-3. HEATER/AIR CONDITIONERMOUNTING

1. Capscrews2. Filter Assembly3. Slotted Head

Capscrews

4. Heater/Air ConditionerAssembly

5. Capscrews

N2-2 Truck Cab N02006 4/92

16. Remove capscrews (5, Figure 2-3) and filter as-sembly (2) to provide the necessary clearance ofheater/air conditioner removal.

17. Release the two latches on the emergency exitwindow (right side) and raise it. Remove slottedhead capscrews (3).

18. Remove the capscrews (1) retaining the heater/airconditioner assembly and carefully lower assem-bly onto the remaining hood structure.

19. Remove rear cover plate near the heater/air con-ditioner controls and disconnect the necessaryelectrical wires from the cab circuit.

The heater/air conditioner assembly weighs ap-proximately 100 lbs. (45.36 Kg). Use caution whileremoving assembly. Make certain heater/air con-ditioner hose retaining clamps are removed fromcab section before attempting assembly removal.It is not necessary to disconnect any heater or airconditioner hoses from assembly to remove fromcab.

20. Slide the assembly off the hinges and secure it outof the way of cab removal.

21. Loosen the capscrews holding the deck structureon the left side of the cab.

22. Position a lifting strap around the center of deckstructure so that its weight is evenly distributedand take up slack.

23. Remove the capscrews and the left deck from thetruck.

24. Disconnect electrical wires on the headlights andturn signal mounted on the left deck structure.

25. Loosen the capscrews holding the front left deckstructure to the cab and attach lifting strap aroundstructure so its weight is evenly distributed. Takeup slack.

26. Remove capscrews and front deck and railing fromtruck position deck structures out of the way.

27. Install four eyebolts (1, Figure 2-5) in tapped padswelded in the roof of the cab. The threads of thetapped pads are 0.62--11 UNC.

FIGURE 2-4. HEATER/AIR CONDITIONERASSEMBLY REMOVAL

1. Hood Structure2. Heater/Air Conditioner Assembly

3. Hinges

FIGURE 2-5. LIFTING CAB ASSEMBLY

1. Eye Bolts 2. Lifting Device

N02006 4/92 Truck Cab N2-3

The integral ROPS cab assembly weighs approxi-mately 2800 lbs. (1271.2 Kg). Make certain liftingapparatus is of adequate capacity.

28. Install lifting device to the four eyebolts in cab roof.As illustrated in Figure 2-5. Take up slack.

29. Remove capscrews (3, 5 and 8, Figure 2-6) fromcab mounting pins under the cab.

30. Drive out pins (2, 6 and 7) from mounting pads andstrut and remove cab assembly from the truck.

Secure the strut to prevent it from swinging downduring pin removal.

Installation

The integral ROPS cab assembly weighs approxi-mately 2800 lbs. (1271.2 Kg). Make certain liftingapparatus is of adequate capacity.

1. Install four eyebolts in tapped pads welded in theroof of the cab. The threads of the tapped padsare .62--11 UNC.

2. Install lifting device to the four eyebolts in cab roofand take up slack.

3. Lift cab into position and install threaded shaft (2,Figure 2-6) and pins (6 and 7).

4. Install capscrews (5 and 8) and tighten to standardtorque. Install clamp structures (1) and locknuts(3) and tighten to 300 ft.lbs. (407 N.m) torque.

5. Remove lifting device and four eyebolts from thecab roof.

6. Install lifting device around the front deck andrailing and lift deck into position on truck.

7. Install all capscrews that retain the deck andrailing in place. Tighten to standard torque.

8. Install lifting device around the left deck andposition it on the left side of the cab.

9. Install capscrews that retain the deck structure inplace. Tighten to standard torque.

10. Connect electrical wires on headlights and turnsignal mounted on front deck structure.

The heater/air conditioner assembly weighs ap-proximately 100 lbs. (45.36 Kg). Use caution whileinstalling assembly.

11. Slide the heater/air conditioner assembly onto thehinges on the right side of the cab and allow theassembly to rest on hood structure.

FIGURE 2-6. CAB MOUNTING POINTS

1. Clamp Structure (two)2. Threaded Shaft3. Locknuts (two)4. Strut

5. Capscrew6. Pin7. Pin8. Capscrew

N2-4 Truck Cab N02006 4/92

12. Connect electrical wires into the rear portion of theassembly to the control switches and install therear cover plate.

13. Swing the assembly up into position on the caband install capscrews (1, Figure 2-3). Tighten tostandard torque.

14. Install the slotted head capscrews (3) into theupper portion of the assembly and tighten tostandard torque.

15. Install filter assembly (2) and capscrews (5).Tighten to standard torque.

16. Install the left section of the hood into position nearright side of cab and capscrews. Tighten to stand-ard torque.

17. Install brake manifold and treadle valve. Tightencapscrews to standard torque.

18. Remove caps and attach hoses to retarder valve.

19. Install throttle control and tighten capscrews tostandard torque. Connect cable and install clevispin and cable anchor.

20. Insert steering control valve (10, Figure 2-2)through cab floor and align splines on valve col-umn with the isolator flange assembly. Install cap-screws (9) through the rubber bushings from thebottom side of the mounting plate (11). Installflatwashers, lockwashers, and nuts. Install cap-screws in isolator flange (3) and tighten to stand-ard torque.

21. Connect the four cannon plug connectors and anyother single harness connectors under the frontpart of the cab bottom.

NOTE: Make certain connections are clean and se-curely hand tightened.

22. Connect transmission and engine circuit wiringinside the cab.

23. Install all harness and hose retaining devicesinside cab and under cab to prevent abrasionand/or damage.

24. Connect battery cables in the following sequence:

a. Install battery negative (-) cable.

b. Install battery positive (+) cable.

c. Turn ATEC power switch ‘‘On’’.

25. Start the engine and check for any hydraulic leaksand for proper operation of instrument panel com-ponents.

26. Remove body-up retaining pin and lower body.

27. Check hydraulic oil; add oil if needed. Refer toSection "P", Lubrication and Service.

Refer to Brake System, Section "J" to bleed thebrake system and to checkout brake circuit beforereleasing the truck for operation.

28. Bleed and check operation of brakes.

Refer to Hydraulic System, Section "L", SteeringCircuit to checkout steering circuit before releas-ing the truck for operation.

29. Check the operation of the steering circuit.

30. Check the operation of the throttle and retardercontrols. Refer to procedures in Section "C" for thethrottle and Section "J" for the retarder if adjust-ments are required.

N02006 4/92 Truck Cab N2-5

Notes

N2-6 Truck Cab N02006 4/92

OPERATOR COMFORT

OPERATOR SEAT The operator’s seat provides a fully adjustable cush-ioned ride for the driver’s comfort and ease of opera-tion. The seat is independently mounted from the cabfor easy maintenance and repair.

Adjustment

The following adjustments must be made while sittingin the seat.

1. To adjust fore/aft location of seat:

a. Raise slide adjustment lever (2, Figure 4-1).

b. Move seat backward or forward as desired.

2. To adjust seat height:

a. Depress the ‘‘Height Adjust’’ lever (1).

b. Adjust seat assembly to desired height.

3. To adjust weight:

a. Turn knob ‘‘Weight Adjust’’ (3).

b. Moving knob clockwise decreases cushioningeffect of seat and turning counterclockwise in-creases cushioning effect.

c. Proper adjustment results in Weight Indicator(4) being flush with seat base while operator isseated.

4. To adjust seat cushion:

a. Raise ‘‘Cushion Tilt Latch’’ lever (3, Figure 4-2)on left side of seat.

b. When lever is unlatched, choose between twodifferent positions.

Removal

1. Remove capscrews, lockwashers and nuts (7,Figure 4-1) that secure seat base to seat riser.

2. Remove seat assembly from cab to clean workarea for disassembly.

Seat Weight: 102 lbs. (46.3 kg).

Installation

1. Mount seat assembly to seat riser. Install cap-screws, lockwashers and nuts. Tighten cap-screws to 35 ft. lbs. (47.5 N.m) torque.

2. Install stop cable ends (2, Figure 4-2) if they wereremoved.

FIGURE 4-1. SEAT ADJUSTMENT CONTROLS

1. Height Adjustment2. Slide Adjustment3. Weight Adjustment4. Weight Indicator

5. Lower Housing6. Boot7. Capscrews,

Lockwashers & Nuts

FIGURE 4-2. STOP CABLE & TILT LATCH

1. Capscrew , Washer & Nut2. Stop Cable

3. Tilt Latch4. Capscrew

N04007 6/98 Operator Comfort N4-1

Disassembly

1. Remove springs (3, Figure 4-3) from spacer bar(39) and link (2).

2. Remove bolts and washers (9) and nuts (4) secur-ing back cushion (5) to side brackets (1 & 7) andremove cushion.

3. Remove link (2) from back of cushion only ifreplacement is necessary.

4. Before starting any further disassembly, adjust theseat height to highest position and turn the weightadjustment lever clockwise to release tensionfrom spring (18).

5. Remove suspension boot (33).

6. Remove spring (8) from side brackets and cush-ions (6).

7. Remove capscrews, nylon washers and nuts (10)securing seat cushion to side brackets. Removeseat cushion.

8. Remove bolts, washers and nuts (41) securingcables (40) and spacer bar (39) to side brackets.

9. Remove locknuts and washers (37) securing sidebrackets to cross link assembly (36). Remove sidebrackets.

10. Remove locknuts (32) and nylon bearings (20) frombearing shafts (19).

Seat spring (18) is under pressure. Use care whenremoving bearing shafts from seat suspension.

11. Remove bearing shafts (19) from seat suspensions(16).

12. Remove upper housing (34) and cross link assem-bly (36) as an assembly.

13. Remove capscrews (38) and springs (35) fromcross links only if replacement is necessary.

14. Remove nylon bearing and locknut (29) from shoul-der bolts (24) securing shock absorber to lowerhousing (27). Remove shock absorber.

15. Remove spring (18) and spring pad (23).

16. Remove nylon slider blocks (17) from seat suspen-sion (16).

17. Remove slide stop (26) and lower housing (27)from slide track (28).

18. Remove rollers (25) from lower housing if replace-ment is necessary.

Inspection

1. Check the shock absorber (30) for oil leakagearound shock absorber shaft. The unit shouldhave a stiff action in one direction, if not, replacewith a new unit.

2. Check and clean nylon tube bearings (20) andnylon slider block bearings (17).

3. Check rollers (25) for wear. Bearings are sealedunits and cannot be greased.

4. Clean and inspect slide track (28) and slide latchassembly (22) on lower housing (27).

5. Inspect teeth on gear and shaft assemblies (14 &15).

6. Inspect spring (12) and teeth on latch (13).

7. Check spring (18) and spring pad (23) for damage.

8. Check rubber bumpers (11) for wear.

9. Add grease where necessary. Clean all parts be-fore assembling seat.

Assembly

1. Mount rollers (25) onto lower housing (27) if re-moved or replaced.

2. Mount lower housing (27) into slide track (28) andinstall slide stop (26).

3. Install nylon tube bearings (20) onto bearing shafts(19).

4. Mount spring (18) and spring pad (23) on lowerhousing.

5. Install nylon slider blocks (17) onto seat suspen-sion (19).

6. Mount seat suspension (16) between lower hous-ing (27) and upper housing (34).

7. Slide lower bearing shaft (19) through lower hous-ing (27) and seat suspension (16). Slide upperbearing shaft through upper housing (34), shockabsorber (30) and nylon bearing (31).

N4-2 Operator Comfort N04007 6/98

FIGURE 4-3. OPERATOR SEAT

1. Left Side Bracket 2. Tilt Back Link 3. Spring 4. Nut 5. Back Rest Cushion 6. Seat Cushion 7. Right Side Bracket 8. Spring 9. Bolt & Washer10. Capscrew, Nylon Washers

& Nut11. Bumper12. Spring13. Latch14. Gear & Shaft Assembly15. Gear & Shaft Assembly16. Seat Suspension17. Nylon Slider Block18. Spring19. Bearing Shaft20. Nylon Tube Bearing21. Spring22. Slide Latch Assembly23. Spring Pad24. Shoulder Bolt25. Roller26. Slide Stop Spacer &

Capscrew27. Lower Housing28. Slide Track29. Nylon Bearing & Locknut30. Shock Absorber31. Nylon Bearing32. Locknut33. Suspension Boot34. Upper Housing35. Spring36. Cross Link Assembly37. Locknut & Washer38. Capscrews39. Spacer Bar40. Cable41. Bolt, Washer & Nut


8. Install lower part of shock absorber (30) and nylonbearings (29) onto lower housing (27) with shoul-der bolts (24) and locknuts.

9. Mount cross link assembly (36) and springs (35)onto lower housing with capscrews (38) if removedor replaced.

10. Install side brackets (1 & 7) onto cross link assem-bly (36) with nuts and washers (37).

11. Install seat cushion (6) onto side brackets andsecure with capscrews, nylon washers and nuts(10).

12. Mount spacer bar (39) and cables (40) to sidebrackets with capscrews, washers and nuts (41).

13. Install springs (8) to side brackets and bottom ofseat cushion.

14. Mount link (2) onto cushion, if removed or replaced.

15. Mount back cushion (5) to side brackets withcapscrews and washers (9).

16. Install springs (3) to spacer bar (39) and link (2).

17. Mount suspension boot (33) onto upper and lowerhousings.

HEATER/AIR CONDITIONER

Heat for the cab is provided by passing coolant fromthe engine cooling system through a heater core. Blow-ers move air across the heating core which warms theair for heating or defrosting.

For heater operation, start the engine and allow it towarm up. Move the toggle switch to the ‘‘Heat’’ position,pull the (push-pull) temperature control knob out andturn the blower to high, medium or low speed fordesired air flow. The temperature control will providemaximum heat output when pulled out as far as possi-ble. To decrease temperature, push the knob in untildesired temperature is attained.

For air conditioner operation, place the toggle switchin the ‘‘A/C’’ position and push the temperature knobin. Adjust the air temperature using the ‘‘A/C TEMP’’knob.

WATER CONTROL VALVEThe water control valve is controlled by a cable leadingto the push-pull temperature control. The lever opensor closes the valve in varying degrees according to theposition of the control knob.

A leaky control valve will allow heated water to passthrough the hose between the valve and the heatercore. If the hose is warm and the push-pull tempera-ture control knob is in the ‘‘cool’’ position, check cableadjustment to be certain that the control valve is beingcompletely closed.

If the hose is still warm after these checks, the controlvalve is leaking and should be replaced. The controlvalve has a directional arrow stamped on the body, thisarrow must point in the direction of flow for valve tooperate properly.

Heater/Air Conditioner Removal

The coolant system is pressurized by thermal ex-pansion of the water. DO NOT remove radiator capwhile engine is hot. Severe burns may result.

1. Relieve radiator pressure by slowly loosening ra-diator cap.

2. To minimize coolant inside operator’s cab, placetemperature control in ‘‘Off’’ position. Close shut-off valve on engine block attached to heater inlethose. Remove hose from valve.

3. Remove capscrews retaining the section of hoodnearest the right side of the cab and set the hoodsection aside.

4. Remove capscrews (5, Figure 4-4) and filter as-sembly (2) to provide the necessary clearance ofheater/air conditioner removal.

5. If removal of heater/air conditioner assembly re-quires the assembly to be completely removedfrom truck, refer to Section ‘‘M’’, Air ConditioningDischarging, to discharge the R-12.

DO NOT disconnect any air conditioning hosesfrom assembly until system is properly discharged.Refer to discharging procedures in Section "M".

6. If required, discharge the air conditioning systemand disconnect hoses to the evaporator. Tightlycap hoses and connections.


7. Loosen clamp securing heater return line (linewithout valve) to heater core. Loosen line until itstarts to leak, then move ‘‘Push-Cool/Pull-Heat’’control knob to ‘‘Heat’’ position. Heater core willdrain through hose removed from the shut-offvalve on the engine block.

NOTE: Make certain return line, loosened in Step 7, issucking air to prevent siphoning of coolant from radia-tor and engine.

8. Release the two latches and raise the emergencyexit window (right side) to provide access to theslotted head capscrews (3).

9. Remove the capscrews (1, Figure 4-4) retainingthe heater/air conditioner assembly and carefullylower assembly onto the remaining hood struc-ture as illustrated in Figure 4-5.

10. Remove rear cover plate near the heater/air condi-tioner controls and disconnect the necessary elec-trical wires from the cab circuit.

The heater/air conditioner assembly weighs ap-proximately 100 lbs. (45.36 Kg). Use caution whileremoving assembly. Make certain heater/air condi-tioner hose retaining clamps are removed from cabsection before attempting assembly removal.

11. Slide the assembly off the hinges.

FIGURE 4-4. HEATER/AIR CONDITIONERMOUNTING

FIGURE 4-5. HEATER/AIR CONDITIONERASSEMBLY REMOVAL


Installation

The heater/air conditioner assembly weighs ap-proximately 100 lbs. (45.36 Kg). Use caution whileinstalling assembly.

1. Slide the heater/air conditioner assembly onto thehinges on the right side of the cab and allow theassembly to rest on hood structure.

2. Connect electrical wires into the rear portion of theassembly to the control switches and install therear cover plate.

FIGURE 4-6. HEATER ASSEMBLY

1. Air Intake Cover2. Housing Assembly3. Core Cover4. Entry Ring5. Blower Assembly6. Motor7. Blower Assembly8. Blower Wheel

9. Motor Retainer 10. Panel11. Water Control Valve12. Heater Core13. Resistor14. Cover Assembly15. Plate

16. Evaporator17. Expansion Valve18. Drain Hose19. Air Diffuser20. Control Panel21. Switch (HI, MED, LO)22. Control Cable

23. Bezel Nut24. Switch (Heat-A/C)25. Thermostat26. Knob27. Louver28. Filter29. Clip Filter (Not Shown)


3. Connect heater hoses, tighten clamps securely toprevent leaks.

4. If removed, connect heater hose to shut-off valveon engine block. Open the shut-off valve.

5. If removed, connect air conditioning hoses toevaporator. Refer to Section M to charge andperformance test the system.

6. Swing the assembly up into position on the caband install capscrews (1, Figure 4-4). Tighten tostandard torque.

7. Install the slotted head capscrews (3) into theupper portion of the assembly and tighten tostandard torque.

8. Install filter assembly (2) and capscrews (5).Tighten to standard torque.

9. Install the left section of the hood into position nearright side of cab and capscrews. Tighten to stand-ard torque.

10. Check coolant level in radiator and refer to Section"P", lubrication and service for appropriate mixtureof antifreeze.

11. Start engine and move the ‘‘Push-Cool/Pull-Heat’’control knob the the ‘‘Heat’’ position. Run enginefor a short time for coolant to completely fill theheater circuit and lines.

12. Shut down engine, recheck coolant level and addcoolant mix, if necessary.

13. Start engine. When unit is up to operating tempera-ture, check out heater/air conditioner system.


Disassembly

1. Remove cover (3, Figure 4-6) from heater assem-bly by removing screws on each side and at upperfront of the cover.

2. Remove both hoses and clamps from heater corefittings.

3. Slide heater core (12) from unit.

4. Remove screws holding motor retainer (9) inplace.

5. Disconnect electrical wiring from blower motor.Wires are color coded for easy identification. Noteproper connection location.

6. Slide out motor and blower assembly from hous-ing (2, Figure 4-6).

7. Remove screws holding entry ring (4) to blowerhousings (5 & 7).

8. Remove entry ring (4).

9. Loosen setscrews on blower motor shafts holdingblower wheels (8) in place.

10. Remove blower wheels (8).

11. Remove two nuts holding each end of motor (6) toblower housings (5 & 7).

NOTE: Mark position of blower housing and fan withrespect to motor to insure proper fan rotation at assem-bly.

12. Remove blower housings.

Inspection

1. Clean and check blower wheels.

2. Check operation of blower motor.

a. If noisy oil bearing.

b. If bearings are loose, repair or replace motor.

3. Clean blower housings (5 & 7).

4. Clean filter (28, Figure 4-6).

5. Clean drain hose (18).

Assembly

1. Install blower housings (5 & 7) on each end ofmotor and secure in place with two machine nutson each side.

NOTE: To insure proper fan rotation, reassemble unitusing match marks made at disassembly.

2. Install blower wheels (8) on blower motor shafts.Position blower wheels and tighten setscrews.

3. Spin blower wheels to make sure wheels do notrub on blower housings.

4. Install entry rings (4) on sides of blower housing(5 & 7). Install and tighten screws.

5. Install motor and blower assembly into housing (2,Figure 4-6).


6. Connect electrical wiring to blower motor. Wiresare color coded for easy identification (Orange,Black).

7. Install motor retainer (9) in place and install ma-chine screws and tighten securely.

8. Slide heater core (12) into housing (2).

9. Install both hoses and clamps to heater core (12)and tighten.

10. Install filter (28) in bottom of housing (2).

11. Install cover (3) to heater assembly mount screwsand tighten.

12. Check operation of ‘‘Push-Cool/Pull-Heat’’ controlknob to see that it works freely.


OPERATOR CONTROLS AND INSTRUMENT PANEL

Access to back of instrument panel to service wiring and gauges can be obtained by removing three capscrews (notshown above) from top of panel and swinging panel toward the operator seat.

OPERATOR CONTROLSThe function and operation of each control is essentialknowledge for proper and safe operation of the ma-chine. The following discussions reference items 1--10in the Operator Controls illustration Figure 5-1.

(1) Steering Column And Controls

The steering column will tilt up and down and telescopein and out to provide a comfortable drive position forthe operator, or move up and away for easy entry andexit.

(2) Dimmer Switch And Turn Signals

The dimmer switch is located in the turn signal lever. Ifheadlights are on low beam, pulling the lever towardthe steering wheel will change headlights to high beam.Pulling the lever again changes headlights back to lowbeam.

Turn signals lights are activated by moving the lever‘‘up’’ to activate right turn lights, and moving the lever‘‘down’’ for left turn lights.

FIGURE 5-1. OPERATOR CONTROLS

1. Steering Wheel2. Turn Signals and Dimmer Switch3. Steering Wheel Tilt Lever4. Horn/Telescope Adjustment

5. Hoist Control6. Retarder Pedal7. Brake Pedal8. Throttle Pedal

9. Cigarette Lighter10. Ash Tray11. Range Selector12. ‘‘DO NOT SHIFT’’ Light

(Not Shown - HAZARD Flasher Switch below Steering Wheel)

N05011 4/94 Operator Controls and Instrument Panel N5-1

(3) Tilt Lever

Adjust the tilt of the steering wheel by pulling the TiltLever toward the steering wheel and moving the wheelto the desired angle. Releasing the lever will lock thewheel in the desired location.

(4) Horn And Telescoping Adjustment

The horn is activated by depressing the center ‘‘but-ton’’. Operation of the horn should be verified beforestarting engine or moving truck.

The steering wheel adjustment may be moved ‘‘in’’ or‘‘out’’ (telescoped) by rotating the housing around thehorn button counterclockwise to unlock the adjust-ment. After selecting the desired position, rotate thehousing clockwise to lock the adjustment.

Hazard Flasher Switch

Not shown in the previous illustra-tion is the ‘‘HAZARD’’ flasherswitch. It is located below thesteering wheel, approximately inthe ‘‘seven O’ clock’’ position. Pull-ing the switch out activates all turnsignal lights, causing all lights to

flash simultaneously. These should be used to mark thetruck when necessary to park an inoperative truck atthe side of the road or other unusual parking place.

(5) Hoist Control Lever

The hoist control lever is a three-position hand oper-ated switch located to the left of the operator seat. Apush button in the center of the control knob must bedepressed to unlock the lever from the neutral position.

Pulling the lever up actuates the hoist circuit causingbody to raise. Hold lever in hoist position until load isdumped. Releasing the lever from the hoist position willplace the body in a hold position.

To lower body, move the hoist lever to the ‘‘Down’’position and release. Releasing the lever, places thehoist control valve in the ‘‘Float’’ position allowing thebody to return to the frame.

(6) Retarder Pedal

The Retarder Pedal is a foot operated pedal whichallows the operator to apply the rear, oil cooled brakesonly; the front brakes are not applied. The retardershould be used to control the speed of the truck andfor non-emergency stops whenever speed and loadconditions permit.

(7) Brake Pedal

The Brake Pedal is a foot operated pedal controlling ahydraulic valve, which applies both, the front dry discbrakes and the rear wet disc brakes. The service brakesshould be used to slow or stop the truck wheneversaftey and/or truck speed/load conditions exceeds thecapability of the retarder.

(8) Throttle Pedal

The Throttle Pedal is a foot operated pedal whichallows the operator to control engine RPM.

(9) Lighter

Used for lighting cigars and cigarettes. Always useCAUTION with smoking materials.

(10) Ash Tray

Used for extinguishing and depositing smoking mate-rials. DO NOT use for flammable materials such aspaper wrappers. Be certain that all fire ash is extin-guished.

FIGURE 5-2. HOIST CONTROL LEVER

N5-2 Operator Controls and Instrument Panel N05011 4/94

(11) Range Selector

The lever-type range selector has eight positions (R,N, D, 5, 4, 3, 2 and 1). To change positions, releasethe range holding mechanism on the lever (just belowthe knob) and move lever to the desired range.

"N" NEUTRAL - used when starting engine. The truckcannot be started unless the Range Selector is inNEUTRAL position.

"R" REVERSE - use this position to back the truck. TheReverse Warning Horn is activated when this gear isselected.

COMPLETELY STOP the truck before shiftingfrom FORWARD to REVERSE or vice-versa.

"D" DRIVE - position. The transmission will shift to firstgear and as truck speed increases, the transmissionwill automatically upshift through each gear to sixthgear operation. As the truck slows down, the transmis-sion will automatically downshift to the correct gear.

5, 4, 3, 2 - positions. Road and load conditions some-times make it desirable to limit the automatic shiftingto a lower range. These positions provide greater en-gine braking on grades. The transmission will not shiftabove the highest gear selected. When conditionsimprove, select position D for full range operation.

1 - Use this gear when pulling through mud and deepsnow, or when maneuvering in tight spaces, whendriving up or down steep grades where maximumdriving power and maximum engine braking is needed.

NOTE: As engine and ground speed increases, thetransmission will automatically UPSHIFT to the gearrange required up to the highest range selected. How-ever, DOWNSHIFTS will not occur, regardless of gearrange selected, until engine and ground speed arereduced to match the next lower gear range require-ments.

(12) Do Not Shift Light

This light comes on anytime the on-board computerfinds a potentially serious problem in the system. Thecomputer will cause the transmission to lock-in-gearand also to disengage the lockup clutch. These actionsby the computer reduces the possibility of damage tothe truck and transmission. The hold-in-gear featureprevents upshifts and downshifts when a problem isdetected in the operation of the transmission. Thehold-in-gear circuit permits the transmission to con-tinue to operate in the gear it was in at the time the DONOT SHIFT light and buzzer came ‘‘On’’. Selection ofa different gear range will have no effect on the trans-mission. The hold-in-gear circuit is released when theengine is shut-off. If the problem causing the DO NOTSHIFT light is still present when the engine is restarted,the transmission will be in ‘‘Neutral’’ and will remain in‘‘Neutral’’ until the probem is corrected.

RESET PROCEDURE - When the DO NOT SHIFT LIGHT and/or CHECKTRANS light (on instrument panel) comes ‘‘On’’, thesystem can be cleared, or reset. To reset, bring thevehicle to a stop at a safe location and shutdownengine. Wait about 10 seconds and restart engine. Ifthe problem is temporary, the DO NOT SHIFT (11) andCHECK TRANS lights will not come back ‘‘On’’ and thetruck can be operated in a normal manner.

FIGURE 5-3. RANGE SELECTOR

11. Range Selector Knob12. ‘‘DO NOT SHIFT’’ Light


INSTRUMENT PANELThe identification, function and operation of each in-strument and control is essential knowledge for properand safe operation of the machine. The following itemsreference the Instrument Panel illustration Figure 5-4,items 1--33. Items marked (OPTIONAL) may not applyto the truck being serviced.

(1) Fog Lights (Optional)

The fog lights are an optionalpiece of equipment, useful inheavy rain and foggy conditions.When present, the switch hastwo positions, ‘‘On’’ and ‘‘Off’’.

(2) Lights--All

The instrument panel lights andthe head lights are controlled bya three position switch. Movingthe switch from the ‘‘Off’’ positionto the second position com-pletes the circuit from battery tothe instrument panel lights andtaillights. Moving the switch to

the third position completes the circuit to the headlights in addition to the panel and tail lights.

(3) Lights-- Instrument Panel

The panel light dimmer control isa rheostat which allows the op-erator to vary the brightness ofthe instrument panel lights.

(4) Windshield Washer

The windshield washer switch,when held in the ‘‘On’’ position,directs water from the reservoir(located in the cab to the left sideof the passenger seat box) to thewindshield for cleaning pur-poses. Wipers (5) should be op-erating when washer is activated.

This switch is spring loaded to the ‘‘Off’’ position. Thewindshield washer has a 2 qt. (2 l) plastic container.

(5) Windshield Wiper

The windshield wiper controlswitch is a three position rockerswitch. Moving the switch from‘‘Off’’ to the second positionplaces the wiper in the low orslow cycle. Pushing the switch tothe third position places thewiper motor in high or fast cycle.

(6) Engine Starting Aid

The ether starting aid is used forcold weather starting and is con-trolled by a switch which isspring-loaded to the ‘‘Off’’ posi-tion. When the switch is held inthe ‘‘On’’ position, the ether is in-jected into the engine intake

manifold to aid in cold weather starting. In coldweather, below 50° F (10° C), turn the keyswitch (7) tothe ‘‘Start’’ position. Push the cold weather startingswitch to the ‘‘On’’ position for three seconds whilecranking, then release. If engine does not start, waitthree seconds before repeating the procedure.

(7) Keyswitch

The key switch is a three position (‘‘Off’’, ‘‘Run’’, ‘‘Start’’)switch. When it is moved to the ‘‘Run’’ position, theswitch activates the accessory circuits. When movedto the ‘‘Start’’ position, the engine’s starting system isactivated. After engine start, allow the switch to returnto the spring-loaded ‘‘Run’’ position.

(8) Engine Shut Down

The engine shutdown switch is aspring return rocker switch that isconnected to the engine shut-down solenoid. In order for thisswitch to work, the keyswitchmust be in the ‘‘Run’’ position.

The engine shutdown switch must be depressed untilthe engine comes to a complete stop. When the switchis held closed, fuel to the engine is shut off.

(9) Windshield Wiper Fuse Holder

This is a 15 amp.- dual element,time delay (slow blow) type fuse.Replacement with any other typeis not recommended.


FIGURE 5-4. INSTRUMENT PANEL


(10) Turn Signal Fuse Holder

This is a 15 amp.- dual element,time delay (slow blow) type fuse.Replacement with any othertype is not recommended.

(11) Circuit Breaker

5 amp circuit breaker protects the warning cluster andthe sound alarm. If a malfunction occurs, the breakerwill open to protect the circuit from excessive current.The circuit breaker can be reset manually by pushingthe red reset button.


15 amp circuit breaker protects the hourmeter and thesteering bleeddown timer. If a malfunction in the cir-cuitry occurs, the breaker will open the circuit. Thecircuit breaker can be reset manually by pushing thered reset button.


30 amp circuit breaker protects the heater blowermotor and the air conditioning system. The circuitbreaker can be reset manually by pushing the red resetbutton.

Investigate cause of any burnt out fuses or circuitbreakers that need repeated resetting. These maybe indications of serious problems that may resultin fire or damage to components if neglected.

(14) Brake Lock

The brake lock switch actuatesthe hydraulic brakes on the rearof the truck. Apply the brake lockswitch while truck is beingloaded. When pulling into theshovel or dump area, do not ap-ply the brake lock switch untiltruck is completely stopped.

(15) and (18) Brake Off

When the Brake Lock switch (14)or Parking Brake switch (17) is inthis position, the brake is off.

(16) and (19) Brake On

When the Brake Lock switch (14)or Parking Brake switch (17) is inthis position, the brake is on.

(17) Parking Brake

To apply parking brake, movecontrol to ‘‘On’’. To release, moveswitch to the ‘‘Off’’ position. Theparking brake is spring appliedand hydraulically released. Whenthe parking brake is actuated, anindicator light (42) will be illumi-nated on the instrument panel.

The parking brake can only be applied with thekeyswitch in the ‘‘Run’’ position and the transmissionrange selector in the NEUTRAL position. The parkingbrake is automatically applied when the engine is shut-down.

The following are not used on 140M/210MHAULPAK® with Rear Wet Disc Brakes

(20) Slippery Road Switch

(21) Switch Open

(22) Switch Closed


(23) Transmission Temperature

The transmission temperaturegauge indicates the temperature ofthe oil during operation. Allowablemaximum operating oil tempera-ture is 250° F (121° C) during non-retarder operation with an absolutemaximum temperature of 300°F(149° C) during intermittent re-

tarder operation. If oil exceeds maximum temperature,safely pull the truck to the side of the road, shift trans-mission to ‘‘Neutral’’ and run engine at 1000-1200 RPMuntil transmission temperature returns to ‘‘Normal’’. Iftemperature does not return to ‘‘Normal’’ within a fewminutes, shut down engine and investigate cause ofproblem. Refer to Section C, Cooling, and/or F, Trans.

(24) Water Temperature

The engine water temperaturegauge indicates the temperatureof the coolant in the engine cool-ing system. The temperaturerange after engine warm-up andtruck operating under normalconditions, should be:

165° F (74° to 91° C).

(25) Transmission Oil Pressure

The transmission oil pressuregauge indicates the pressure in thetransmission clutch system inpounds per square inch (psi).

Normal operating pressure afterwarm-up should be:

170 to 210 psi (1172-1448 kPa).

(26) Engine Oil Pressure

The engine oil pressure gauge in-dicates the pressure in the enginelubrication system in pounds persquare inch (psi). The gauge has arange of 0-80 psi.

Normal operating pressure after engine warm-upshould be:

Idle: 20 psi (138 kPa)

Rated Speed: 45 to 70 psi (310 to 483 kPa).

(27) Brake Oil Temperature

The brake oil temperature gaugeindicates the temperature of therear brake cooling oil during op-eration. Maximum operating oiltemperature is 250° F (121° C). Ifoil temperature exceeds this maxi-mum, Brake Oil TemperatureWarning light (48) will turn on. As

quickly as safety will permit, bring the truck to a com-plete stop away from traffic, move transmission rangeselector to ‘‘Neutral’’, apply the parking brake, and runengine at high idle. Continue to run engine at high idleuntil Brake Oil Temperature Warning light turns off andbrake oil temperature cools to below 250° F (121° C).Iftemperature does not return to this range within a fewminutes, shut down engine and investigate cause ofproblem. Refer to Section J.

(28) Voltmeter

The voltmeter indicates the out-put voltage of the battery charg-ing alternator. Normal indicatedvoltage at high idle is 27 to 28volts. When the keyswitch is ‘‘On’’and the engine not running, thevoltmeter indicates battery volt-age.

(29) Speedometer

The speedometer indicates the truck speed in miles perhour (MPH) and kilometers per hour (km/h).

(30) Left Turn Indicator (Red Light)

This light flashes to indicate thatthe left turn signal lights on thetruck have been activated. It willalso flash simultaneously with rightturn signal indicator (32) when‘‘Hazard’’ switch (on steering col-umn) is On.

(31) High Beam Indicator (Blue Light)

The high beam indicator light,when lit, indicates that the truckheadlights are on ‘‘High’’ beam. Toswitch headlights to ‘‘High’’ or‘‘Low’’ beam, pull lever-operateddimmer switch (turn signal lever)and release.


(32) Right Turn Indicator (Red Light)

This light flashes to indicate thatthe right turn signal lights on thetruck have been activated. It willalso flash simultaneously with leftturn signal indicator (30) when‘‘Hazard’’ switch (on steering col-umn) is On.

(33) Tachometer and Hourmeter

This gauge includes an Hourmeter to register enginehours of operation and a Tachometer which registersengine speed in hundreds of Revolutions Per Minute(RPM).

Engine Speeds:

Low Idle - 700 ± 25 RPM.

High Idle, No load - 2450 RPM

Governed Speed - 2100 RPM

Retarder Operation

When approaching a descending grade, the operatorshould slow the truck and select the proper transmis-sion gear range to maintain an engine speed of 1650 --2350 RPM (green area on tachometer) and the brakeoil temperature below 250° F (121° C) during retarderoperation. Refer to the Grade/Speed decal in the cababove the windshield.

When descending a grade, the operator should applythe retarder pedal and observe both the Tachometerand the Brake Oil Temperature Gauge (27). The engineRPM must be maintained at 1650 -- 2350 RPM (greenarea on tachometer) and the Brake Oil Temperaturemust be maintained below 250° F (121° C).

If the operator observes that either the maximum en-gine speed of 2350 RPM or the Brake Oil Temperatureof 250° F (121° C) are about to be exceeded, theoperator should immediately move the transmissionrange selector to the next lower range and apply theservice brakes until the truck is slowed to a speedwhich will permit the transmission to downshift to thegear range selected. Continue this procedure to down-shift to the required gear range to maintain enginespeed at 1650 -- 2350 RPM and brake oil temperaturebelow 250° F (121° C). The service brakes should beused only long enough to slow the truck to allow thetransmission to downshift. When the proper gear rangeis attained, continue using the retarder to maintain asafe, productive speed.

If brake oil temperature exceeds 250° F (121° C), theBrake Oil Temperature Warning light (48) will turn on.As quickly as safety will permit, bring the truck to acomplete stop away from traffic, move transmissionrange selector to ‘‘Neutral’’, apply the parking brake,and run engine at high idle. Continue to run engine athigh idle until Brake Oil Temperature Warning lightturns off and brake oil temperature cools to below 250°F (121° C). If temperature does not return to this rangewithin a few minutes, shut down engine and investigatecause. Refer to Section J.


INSTRUMENT PANEL -- RIGHT SIDEThe following discussions (items 34--54) are referencedto Figure 5-5. This area contains the Warning indicatorsthat will illuminate in the event that a monitored systemshould malfunction. The operator or service technicianshould immediately recognize all of these indicatorsso that emergency action may be exercised whennecessary.

(34) Equal Fault Light

The charge condition of the two 12 Volt batteries ismonitored to make sure that both batteries are beingcharged equally. The Equal Fault Light will illuminate ifmore than a 0.85 volt variance between the two batter-ies is detected.

(35) CHECK TRANS Light

The ATEC system has a built in computer (ECU) thatmonitors various functions and performances. Whenthe computer senses that the system is not performingproperly, the CHECK TRANS light comes ‘‘On’’ to warnand alert the operator that a problem has occurred andthat the vehicle should be serviced as soon as possible.The CHECK TRANS light will come ‘‘On’’ when theignition is turned ‘‘On’’. After about two seconds, thelight will go ‘‘Off’’. This provides a light bulb check anda system check.

In cold weather, when the transmission oil is below -10°F (23° C), the DO NOT SHIFT lights on the range

selector and the CHECK TRANS light will stay on afterthe engine is started. The transmission will stay inNEUTRAL, regardless of which range is selected untilthe oil is warmer than -10° F (-23° C). When the trans-mission oil warms up, the CHECK TRANS and DO NOTSHIFT lights will turn off and the transmission willoperate in first gear or reverse only. At 20° F (-7° C), thetransmission may be operated safely in all ranges.

If the transmission oil temperature reaches 250° F(121° C), the CHECK TRANS indicator light will come‘‘On’’. The ECU (Electronic Control Unit) will inhibitoperation of the truck in higher gears.

NOTE: The Transmission Temperature Gauge (23)indicates the converter temperature. The ECU sensesoil temperature in the sump. The two temperaturesmay be different.

FIGURE 5-5. INSTRUMENT PANEL WARNING INDICATORS

SUMP OIL TEM-PERATURE

‘‘DO NOTSHIFT’’LIGHT

‘‘CHECKTRANS’’LIGHT

TRUCK OPERATION

-10° F (-24° C) andBelow ON ON Neutral Only

-9° F (-22° C) to+ 19° F (-7° C) OFF OFF Neutral, First &

Reverse Only

+ 20° F (-7° C) andAbove OFF OFF Full Operation in

All Ranges


(36) ALT FAULT Light

This light will illuminate if the alternator output exceeds30 VDC or battery voltage is less than 24 VDC.

(37) Lamp Test Switch

The lamp test switch is providedfor the operator to test the warn-ing and indicator lights before en-gine start-up. The key switch isturned to the ‘‘Run’’ position andthe lamp test push button switchis depressed to the ‘‘On’’ position.This action will complete a circuit

to the warning and indicator lights.

(38) Alarm Horn

The alarm horn is a signaling deviceused to alert the operator of a malfunc-tion within a system. The alarm hornsenses low steering pressure and lowbrake pressure. When the alarm hornsounds during operation, a warninglight will come ‘‘On’’. This warning light

(39 or 41) will be the operator’s visual aid in determiningwhich system is malfunctioning.

(39) Emergency Steering

The Emergency Steering Light,when actuated, indicates that thesteering circuit pressure is de-creasing and is below 1800 psi(12.4 MPa).

If the light comes ‘‘On’’, stop the truck immediatelyand check the system. Do not attempt further op-eration until malfunction is located and corrected.Refer to Section L.

(40) Brake Lock

The Brake Lock light is on onlywhen the brake lock switch hasbeen activated by the operator.The light indicates that only therear brakes have been applied.The brake lock switch is to beused only at the shovel or dumparea.

(41) Low Brake Pressure Warning Light

This light indicates a malfunctionwithin the hydraulic brake circuit.The low brake pressure warninglight indicates that the hydraulicpressure in the brake system isdecreasing and is below 2000 psi(13.8 MPa).

When the pressure drops to 1650 psi (11.4 MPa),all brakes will automatically be fully applied to stopthe truck. If this light comes ‘‘On’’ when the brakepedal is depressed or comes ‘‘On’’ continuously,shut-down the truck and investigate cause of prob-lem. Refer to Section J.

(42) Parking Brake

The Parking Brake light indicatesthat the parking brake switch hasbeen moved to the ‘‘On’’ positionor that the park brake is ‘‘On’’. Donot use the parking brake whileloading or dumping.

(43) Coolant Temperature Light

This light indicates the enginecoolant temperature has ex-ceeded 200° F (93° C).

If light comes On, bring truck to a safe stop as soonas possible out of way of traffic. Move transmissionrange selector to Neutral and operate engine at1500 RPM until light goes out, or for about 3minutes. If light does not go out, shut engine downand investigate cause of problem. Refer to SectionC.


(44) Coolant Level

This light indicates the coolantlevel in the radiator is low. If lightcomes On, bring truck to a safestop as soon as possible out ofway of traffic. Check coolant leveland refill as required.

(45) Transmission Main Filter

The Transmission Main Filter lightalerts the operator that oil passingthrough the filter elements is be-ing restricted. Occasionally, thewarning light may come on andflicker; but when the light comeson and remains on, the filtersshould be changed as soon as

possible. This warning light may come on at startupand remain lit until the transmission oil is warm.

(46) Engine Oil Pressure

The Engine Oil Pressure Warninglight will come ‘‘On’’ indicating en-gine oil pressure is below normaloperating range.

If light comes On, bring truck to a safe stop as soonas possible out of way of traffic. Shut engine downimmediately and investigate cause of problem.Serious damage may result to engine if operatedwithout sufficient lubricating oil pressure.

(47) Hydraulic Oil Filter

The Hydraulic Oil Filter light indi-cates that the oil passing throughthe filter elements is being re-stricted. Occasionally, the warn-ing light may come on and flicker;but when the light comes on andremains on, the filters should bechanged as soon as possible.

(48) Brake Oil Temperature

The Brake Oil Temperature warn-ing light indicates brake coolingoil has exceeded 250° F (121° C)

If light illuminates during operation, bring the truckto a stop as quickly as safety will permit, away fromtraffic. Place the transmission range selector to‘‘Neutral’’, apply the parking brake, and operate theengine at high idle. Continue to run the engine athigh idle until the Brake Oil Temperature warninglight turns off and brake oil temperature cools tobelow 250° F (121° C). If temperature does notreturn to this range within a few minutes, investi-gate the cause. Refer to Section C for informationregarding brake system cooling.

( 49) Transmission Cooler Filter

The transmission Cooler Filterlight alerts the operator that oilpassing through the elements, inthe filter assembly, is being re-stricted. Occasionally, the warn-ing light may come on and flicker;but when the light comes on andremains on, the filters should be

changed as soon as possible. The TransmissionCooler Filter Warning light may come on at startup andremain lit until the oil is warm.

(50) Low Accumulator Precharge Warning Light

The Low Accumulator PrechargeWarning light, when lit, indicatesa low steering accumulator nitro-gen precharge. If the nitrogenprecharge within the accumula-tors falls below 850 psi (5.9 MPa)the warning light will illuminate.

Do not attempt to operate truck until the accumu-lator has been recharged to 1050 ± 25 psi (7.2-7.5MPa).


(51, 52, 53, 54): Reserved for future accessories.

HEATER/AIR CONDITIONERCONTROLSThe following (items 55--60) are referenced to Figure5-6.

(55) Fan

The fan switch controls theheater/air conditioner three-speed blower motor. The speedsare High, Medium, and Low.

(56) Temperature Control Knob

The push/pull knob controls the amount of hot waterthat will flow through the heater core to heat the air asit passes through the core and circulates throughoutthe cab.

(57) Louvers

The louvers can be rotated or adjusted to direct theflow of air to any part of the cab for the operator’scomfort.

(58) Heater/Air Conditioner Switch

The heater/air conditioner switch is a three-positiontoggle switch. When the switch is moved to the ‘‘Heat’’position, the blower motor is ‘‘On’’ and can be control-led by the three-position fan switch (55). If the switchis moved to the air conditioning position, the compres-sor magnetic clutch is turned ‘‘On’’ and the compressorwill deliver R-12 refrigerant to the evaporator coil in theheater/air conditioner unit in the cab.

(59) Air Conditioning Temperature Control

The thermostatic switch controlsthe temperature of the air enteringthe truck cab. The control is set bythe operator as desired.

(60) Inside/Outside Air Control Knob

The inside/outside air control knob is connected to avent, which allows either outside or inside air to becirculated through the heater assembly. Pulling theknob out permits inside air to be recirculated throughthe heater. Pushing the knob all the way in permitsoutside air to circulate through the heater assembly.

FIGURE 5-6. HEATER/AIR CONDITIONERCONTROLS


THROTTLE PEDAL

The Throttle Pedal (1, Figure 5-7) is a foot operatedpedal which allows the operator to control engine RPM.The treadle is mechanically connected by a cable tothe engine fuel pump. The movement of the fuel pumplever corresponds directly to travel of the pedal as it isapplied by the operator. The fuel pump lever controlsfuel to the engine to control engine RPM. When thepedal is released, the return spring returns the pedaland fuel lever to their original position and the enginespeed returns to low idle.

Removal

1. Remove cotter pin (3, Figure 5-8) and clevis pin (2)from clevis (4).

2. Remove cable anchor (1) and separate cable frompedal assembly.

3. Roll cable in a loop and position it in an out-of-the-way place.

4. Remove capscrews, lockwashers and nuts hold-ing pedal assembly to cab floor.

5. Remove pedal assembly to maintenance area forinspection and repair.

Installation

1. Install pedal assembly on cab floor using cap-screws, lockwashers and nuts. Tighten cap-screws to standard torque.

2. Inspect control cable for corrosion and any dete-rioration that could cause the cable to bind. Re-place if necessary.

3. Install cable clevis (4) into pedal assembly. Insertclevis pin (2) and cotter pin (3) into place.

4. Tighten jam nut to secure clevis in place.

5. Secure cable onto pedal assembly by installingcable anchor (1) in place.

6. Check operation of linkage and adjust if neces-sary. Refer to Section C, ‘‘Engine Components’’for cable adjustment.

FIGURE 5-7. THROTTLE PEDAL ASSEMBLY

FIGURE 5-8. CONTROL CABLE REMOVAL

1. Cable Anchor2. Clevis Pin

3. Cotter Pin4. Clevis


Disassembly

Note orientation of the cable hanger assembly duringdisassembly to insure correct cable routing when in-stalled.

1. Remove spring clip (5, Figure 5-9) from pin (3) andremove pin (3) from block (4) and pedal.

2. Remove spring clip (16) from pivot pin (15) andseparate pivot pin from pedal (14).

3. Remove block (4) from fork (push-rod) (13).

4. Remove nuts (11) and lockwashers (10) fromU-bolt (9) and bracket (8).

5. Separate fork (13) from pedal base and removebellows (32).

6. Remove clip (2) from plate hanger (21). Separatebearing (1), lever (12) and spring (7) from platehanger. Remove bolt (27) and travel stop (28)from lever (12).

7. Remove spring clip (5) from pin (6) and separatefork from lever (12).

FIGURE 5-9. THROTTLE CONTROL PEDAL

1. Bearing2. Clip3. Pin4. Block5. Spring Clip6. Pin7. Spring8. Bracket

9. U-Bolt10. Lockwasher11. Nut12. Lever13. Fork14. Pedal15. Pin16. Spring Clip

17. Bracket18. Capscrew19. Nut20. Washer21. Hanger22. U-Bolt23. Shim24. Nut

25. Bolt26. Nut27. Bolt28. Travel Stop29. Clevis30. Cotter Pin31. Clevis Pin


Inspection

1. Wash all parts in cleaning solvent and blow dry.

2. Check bellows (32) for cracks or cuts.

3. Inspect all parts for excessive wear.

4. Check spring (7) for corrosion.

5. Replace any damaged or worn components.

Assembly

1. Mount fork (13, Figure 5-9) to lever (12) using pin(6) and spring clip (5).

2. Assemble plate hanger (21), bearing (1), spring (7)and lever (12) together and secure in position withclip (2). Mount bolt (27) and travel stop (28) tolever, if removed.

3. Mount rubber bellows (32) on pedal base andinsert fork (push-rod) (13) through rubber bellows(32).

4. Mount plate hanger (21) and lever (12) assemblyto pedal base using U-bolt (9), bracket (8), lock-washers (10) and nuts (11). Tighten nuts securely.

5. Thread block (4) onto fork (push-rod) (13).

6. Mount pedal (14) onto pedal base using pivot pin(15) and spring clip (16).

7. Slide pin (3) through block (4) and pedal and installmount spring clips (5).

8. Lubricate treadle mechanism with a light weight oiland check operation of unit.


NOTES


SECTION P

LUBRICATION AND SERVICE

INDEX

LUBRICATION AND SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-1

LUBRICATION SPECIFICATIONS CHARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-1SERVICE CAPACITIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-1ANTI-FREEZE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-1OIL AND GREASE SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . P2-2

10 HOUR LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . . . . . . P2-3

100 HOUR LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . . . . . P2-5

250 HOUR LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . . . . . P2-7

1000 HOUR LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . . . . P2-9

5000 HOUR LUBRICATION AND MAINTENANCE CHECKS . . . . . . . . . . . . . . . . . . P2-10

P01008 4/92 Index P1-1

NOTES

P1-2 Index P01008 4/92

LUBRICATION AND SERVICE

Preventive Maintenance will contribute to the long lifeand dependability of the HAULPAK® truck and itscomponents. The use of proper lubricants and theperformance of checks and adjustments at recom-mended intervals is most important.

The service intervals presented here are in hours ofoperation and are recommended intervals in lieu ofan oil analysis program which may determine dif-ferent intervals. However, if truck is being operatedunder extreme conditions, some or all of the intervalsmay need to be shortened and the service performedmore frequently.

Periodic routine maintenance should include a thor-ough cleaning and washing of the complete truck.Periodic thorough cleaning is necessary to keepbreathers free of mud build-up, linkage free moving,and to allow for careful inspection of all components(including main frame) for evidence of cracks, deterio-ration of rubber parts (deck bushings) and leakage.Local conditions should dictate the frequency of suchperiodic cleaning and inspection, but every 1,000hours should be considered a minimum.

Refer to manufacturer’s service manual when servicingthe engine or any components of the Allison transmis-sion system.

Lubrication requirements are referenced to the lubekey found in the Truck Lubrication SpecificationsChart. For detailed service requirements for specificcomponents, refer to the service manual section forthat component (i.e. Section "G" for Final Drive, Section"H" for Suspensions, etc.).

210M SERVICE CAPACITIES

Cooling System

Crankcase -- Cummins(includes lube oil filters)

Hydraulic System (incl tank)

Hydraulic Tank

Fuel Tank

Final Drive

Front Spindle

Transmission

48

14.2

144

95

154

56

1

22

181.7

53.8

5451

3601

583.7

212.2

3.8

83.4

Gallons Liters

COOLING SYSTEM ANTI--FREEZE RECOMMENDATIONSEthylene Glycol Permanent Type Anti-Freeze

10202530354045505560

Percentage ofAnti-Freeze

Protection to:

°F °C

+ 23+ 16+ 11+ 4

-3-12-23-34-48-62

-5-9

-11-16-19-24-30-36-44-52

Use only antifreeze that is compatible with engine asspecified by engine manufacturer.

TEMPERATURE CHART FOR C-4 FLUIDS

P02009 4/94 Lubrication and Service P2-1

LUBRICATION SPECIFICATIONS

LUBEKEY

TYPE LUBRICANT -65oF TO -25oF -25oF TO + 32oF + 32oF T0 + 90oF ABOVE 90oF

A ENGINE OIL SEE ENG. MANUAL* SEE ENG. MANUAL* SEE ENG. MANUAL SEE ENG. MANUAL

AA LUBRICATING OIL SAE 10W SAE 10W SAE 10W SAE 10W

B MULTI-PURPOSE GREASE MIL-G-10924B MIL-G-10924B MIL-G-10924B MIL-G-10924B

C MULTI-PURPOSE GEAR OIL MIL-L-2105CSAE 75W

MIL-L-2105CSAE 80W-90



D HYDRAULIC OIL C-4

MIL-L-2104DSAE 10W

MIL-L-2104DSAE 10W

MIL-L-2104DSAE 10W

MIL-L-2104DSAE 10W

E MOLYBDENUM DISULPHIDE GREASE -3% MIN # 0 # 1 # 2 # 2

DESCRIPTION SYM. PTS. LUBE KEY 10 HR

100 HR

250 HR

1000HR

BODY HINGE PINS 1 2 E GREASE

PANHARD ROD 2 2 E GREASE

FINAL DRIVE 3 * * C CHECK CHANGE

FINAL DRIVE BREATHER 4 * * CLEAN

HOIST CYLINDER PIVOTS 5 4 E GREASE

FINAL DRIVE PIVOT PIN 6 1 E GREASE

HYDRAULIC TANK 7 1 D CHECK CHANGE

HYDRAULIC FILTER 8 2 CHANGE

FRONT WHEEL BEARINGS 9 2 C CHECK

FUEL FILTERS 10 2 CHANGE

ENGINE AIR CLEANER 11 1 CHECK

ENGINE LUBE FILTERS 12 2 CHANGE

STEERING BALL STUD/PIVOT 13 6 E GREASE

HYDRAULIC TANK BREATHER 14 2 CHECK CHANGE

ENGINE CRANKCASE OIL 15 1 A CHECK CHANGE

TRANSMISSION OIL FILTER 16 1 CHANGE

TRANSMISSION OIL 17 1 D CHECK CHANGE

TRANSMISSION COOLER FILTER 18 1 CHANGE

U-JOINT CROSSES 19 4 B GREASE

U-JOINT SLIP SPLINE 20 2 E GREASE

SUSPENSION BEARINGS 21 4 E GREASE

ENGINE CRANKCASE BREATHER 22 4 CLEAN

FUEL TANK BREATHER 23 1 CLEAN

FUEL TANK -- H20 & SEDIMENT 24 1 DRAIN

STEERING COLUMN BEARINGS 25 2 B GREASE

THROTTLE CABLE LINK 26 2 AA OIL

CAB DOOR HINGE 27 3 AA OIL

* AUXILIARY HEATERS REQUIRED BELOW -10o F.

** SEE MANUAL

LUBRICATION CHART

WA9847

10 HOUR (DAILY) INSPECTIONPrior to each operating shift, a "walk around" inspectionshould be performed. Check the truck for generalcondition. Look for evidence of hydraulic leaks; checkall lights and mirrors for clean and unbroken lenses;check operator’s cab for clean and unbroken glass;check frame, sheet metal and body for cracks. Notifythe proper maintenance authority if any discrepanciesare found. Give particular attention to the following:

CHECK ALL FLUID LEVELS

a. Engine oil --

NOTE: Refer to engine manufacturer servicemanual for oil recommendations.

b. Radiator -- Check coolant level and fill with propermixture as shown in Cooling System Recommen-dation Chart.

c. Battery -- Check electrolyte level and add water ifnecessary.

d. Hydraulic tank -- Check oil level in tank, add ifnecessary. Lube key ‘‘D’’, C-4 hydraulic fluid.

NOTE: Check hydraulic oil level with truck level,engine idling, body down, and oil warm. Oilshould be visible in sight glass. -- DO NOT OVERFILL. --

Check that breathers are open to atmosphere.Remove any debris or mud build-up.

e. Transmission -- Check oil level. If necessary, addoil. Refer to Section "F" for "Transmission Fill In-structions". Lube key ‘‘D’’, C-4 hydraulic fluid.

NOTE: Check transmission oil level with trucklevel, engine running, oil at operating tempera-ture, and transmission in neutral. Oil level shouldbe not more than half full in sight glass or justtrickle from top (full) petcock (or should be justbelow the FULL mark). DO NOT OVERFILL.

f. Fuel Tank -- Fill as required.

g. Final drive -- Check oil level in sight glass. Truckshould be on level surface; oil should fill sightglass.Check that breather Is open to atmosphere. Re-move any debris or mud build-up.

Truck Serial Number ____________________________

Site Unit Number ______________________________

Date:______________Hour Meter_________________

Serviceperson Name___________________________

COMMENTS √’d INITIALS


10 HOUR (DAILY) INSPECTION(continued)

AIR CLEANERS

a. Check service indicator. If indicator shows red,replace with clean filters. Reset indicator by press-ing button on top of indicator.

b. Empty air cleaner dust cups. See Section ‘‘C’’ ofthe service manual. Remove and empty aircleaner dust cups.

DRIVE BELTS

a. Check alternator and fan belts for proper tensionand condition.

b. Inspect for alignment.

ENGINE AND TURBOCHARGERS

Inspect for leaks, vibrations or odd noises.

TIRES

After each wheel mounting operation, recheckwheel mounting capscrew tightness after aboutfive hours operation. Check again at the end of theshift and then periodically until all capscrews holdat the prescribed 300 ft.lbs. (407 N.m) torque. Thisrequirement is prescribed for both front and rearwheels.

a. Inspect for proper inflation and wear.

b. Inspect for debris embedded in cuts or tread.

LUBRICATION

a. Panhard Rod -- Grease pins and bushings atgrease fittings. Lube Key ‘‘E’’. (2 pts.)

b. Final Drive Pivot Pin -- Grease bushing at greasefitting. Lube Key ‘‘E’’. (1 pt.)

c. Body Hinge Pins -- Grease pins and bushings atgrease fittings. Lube Key ‘‘E’’. (2 pts.)

d. Hoist Cylinder Pivots -- Grease pins and bush-ings at grease fittings. Lube Key ‘‘E’’. (4 pts.)

e. Steering Ball Studs/Pivot and Tie Rod -- Greasebearings and pins at grease fittings . Lube Key ‘‘E’’.(6 pts.)

f. Suspension Bearings -- Grease pins and bush-ings at grease fittings. Lube Key ‘‘E’’. (4 pts.)


P2-4 Lubrication and Service P02009 4/94

100 HOUR LUBRICATION AND MAINTENANCE CHECKSNOTE: 10 Hour service should be included with thefollowing:

CAB

a. Steering Column Linkage -- Use hand gun andlubricate with grease. Lube Key ‘‘E’’. (2 pts.)

b. Cab Door Hinges -- Oil hinges as necessary. LubeKey ‘‘AA’’ (SAE 10W). Check door & windows forproper operation, correct as required.

c. Cab Air Filter -- Clean or replace.

d. Cab Mounts -- Check rubber cab mounts, replaceas required.

e. Outside Mirrors And Lights -- Check for damageand operation, repair as required.

f. Instrument Panel -- Check instruments for properoperation. Verify operation of all lights and warn-ing devices. Check alternator charging rate. Cor-rect as required.

FRONT WHEEL --

Check front wheel bearing oil level. Lube Key ‘‘C’’.

NOTE: To check oil in front wheel hub, rotatewheel hub until one fill/drain hole is horizontal,and the other is "up", add lube oil as required.

THROTTLE CABLE LINKAGE --

Oil linkage with SAE 10W oil (Lube Key ‘‘AA’’).

BRAKES --

Check hydraulic brake control valve, brake cali-pers, brake pads, hoses and tubes for leaks orwear, repair as required.

U-JOINTS/DRIVE SHAFTS --

Use hand gun and lubricate at grease fittings onthe cross and bearing assemblies and splines.Lube Key ‘‘E’’ (6 pts.).

FUEL TANK --

Drain water and sediment from fuel tank.

HYDRAULIC TANK BREATHER --

Remove spin-on breathers and check breathersfor cleanliness. Replace as necessary.

Truck Serial Number ____________________________Site Unit Number _____________________________Date:______________Hour Meter_________________ Serviceperson Name___________________________



100 HOUR LUBRICATION AND MAINTENANCE CHECKS(continued)

FINAL DRIVE --

Check oil level. Add oil as required. Lube Key ‘‘C’’.

FINAL DRIVE BREATHER --

Remove and clean.

REAR HYDRAIR SUSPENSION --

Grease bearings. Lube Key ‘‘E’’. (4 pts.).

SUSPENSIONS --

Check suspension cylinders for leaks (more than50% of dirt ring washed away). Check for properextension. Refer to service manual, Section "H" ifservicing is required.



250 HOUR LUBRICATION AND MAINTENANCE CHECKSNOTE: 10 Hour and 100 Hour service should be in-cluded with the following:

ENGINE

a. Crankcase Oil -- Change engine oil (use Lube Key‘‘A’’ on Lubrication and Specification chart) andcorrosion filters.

b. Lube Oil Filters -- Change.

c. By- Pass Filter -- Change.

d. Other EngineChecks --

• Remove primary air filters if indicator showsRED. Clean or replace as required.

• Change safety filter when green dot disappearsfrom wing nut on safety element. If safety ele-ment is disturbed, replace O-ring seal.

• Check air filter cover gasket, replace as re-quired.

• Check radiator, water pump, hoses and pipesfor leaks, replace or repair as required.

• Check cooling system for correct coolant mix-ture. Add mixture as required.

• Check exhaust manifolds, gaskets, pipes &exhaust box for leaks, repair as required.

• Check lubrication hoses and pipes for leaks,replace or repair as required.

FUEL FILTER AND STRAINER -

Change filter and strainer element.

HYDRAULIC FILTERS -

Change 2 filter elements.

OTHER CHECKS AND ADJUSTMENTS -

Check hydraulic tank, lines, valves and cylindersfor leaks and/or wear, repair as required.

Check orbitrol steering control unit for binding,steering column for excess play, hoses and tubesfor wear or leaks, steering cylinders for excessiveplay or leaks, repair as required.

Check parking brake actuator, hoses and tubesfor leaks or wear, repair as required.

Check parking brake adjustments (lining and link-age), adjust/repair as required.

Truck Serial Number ____________________________Site Unit Number ______________________________Date:______________Hour Meter_________________ Serviceperson Name___________________________



NOTES


1000 HOUR LUBRICATION AND MAINTENANCE CHECKSNOTE: All 10, 100, and 250 hour service points shouldbe included with the following:

ENGINE -

Remove and clean breather elements.

Check engine mounts, repair as required.

Adjust/replace fuel injectors as required.

Adjust intake and exhaust valves as required(Cummins recommends 1500 hours).

FUEL TANK -

Remove breather and clean in solvent. Dry withair pressure.

Drain water and sediment from fuel tank.

TRANSMISSION -

Remove and clean magnetic plug and drain trans-mission oil.Remove and clean sump strainer.Remove, clean, oil and replace breather.

Refill transmission oil. Lube Key ‘‘D’’.

TRANSMISSION FILTERS -

Change transmission oil and oil cooler filter elements.

HYDRAULIC TANK -

Drain hydraulic oil. Remove, clean magnetic plug.Change filter elements. Refill with oil. Use LubeKey ‘‘D’’, C-4 hydraulic fluid.

HYDRAULIC TANK BREATHER -

Install new breather.

FINAL DRIVE -

Change final drive oil. Lube Key ‘‘C’’. Fill final drivehousing at rear fill plug until oil level is at bottomof fill hole. Oil must flow from center housing outto both planetaries; add oil until level is maintainedat bottom of hole. Allow approximately 15 minutesfor proper fill. NOTE: Long, high speed runs and high operatingtemperature may require a more frequent changeinterval.




1000 HOUR LUBRICATION AND MAINTENANCE CHECKS(continued)

OTHER CHECKS AND ADJUSTMENTS -

Check and record hydraulic pressures:

- Steering pressure RH and LH -- 2750 psi (19.0 MPa).

- Hoist up pressure -- 2750 psi (19.0 MPa).

- Hoist down pressure -- 1000 psi (6.9 MPa).

- Hoist valve pilot pressure -- 125 psi (0.9 MPa).

- Brake pressure - all wheels.

- Correct hydraulic pressure as required.

- Check Rear Oil Brake Disc Wear (Use tool installed; Refer to service manual, Section "J", Rear Wet Disc Brakes)

Check steering and brake accumulator prechargepressure -- 1050 psi (7.2 MPa).

NOTE: SERVICE ACCUMULATORS WITH DRYNITROGEN ONLY.

NOTE: For specific checkout procedures or addi-tional information, refer to service manual.



5000 HOUR LUBRICATION AND MAINTENANCE CHECKS NOTE: All 10, 100, 250, and 1000 hour service pointsshould be included with the following:

FRONT WHEELS -

Drain oil and check bearing preload as covered inSection ‘‘G’’ of the Service Manual. Use Lube Key‘‘C’’.

AIR CLEANER -

Clean the Donaclone Tubes in the pre-cleanersection of the air filter. Use low pressure coldwater or low pressure air to clean tubes.

NOTE: Do not use a hot pressure washer or highpressure air to clean tubes because pre-cleanertubes will distort.

STEERING CONTROL FILTER -

Change or clean in-line filter at orbitrol steeringcontrol unit inlet line.

RADIATOR -

Clean cooling system with a quality cleaning com-pound. Flush with water. Refill system with anti-freeze and water solution. Check Cooling SystemRecommendation Chart for correct mixture.Maintain cooling system according to enginemanufacturer’s recommendations.

NOTE: For additional or more specific information,refer to service manual.




NOTES


SECTION QALPHABETICAL INDEX

AAccumulator

Brake . . . . . . . . . . . . . . . . . . . . L6-1Shuttle Valve . . . . . . . . . . . . . . . . . J2-2Steering . . . . . . . . . . . . . . . . . . . L6-1

Actuator, Park Brake . . . . . . . . . . . . . J7-2Air Cleaner Engine . . . . . . . . . . . . . . . C5-1

Pre-cleaner Section . . . . . . . . . . . . . C5-4Air Conditioning Circuit . . . . . . . . . . . . D3-7Air Conditioning System . . . . . . . . . . . M9-1

Charging . . . . . . . . . . . . . . . . . . M9-20Components . . . . . . . . . . . . . . . . M9-3Discharging . . . . . . . . . . . . . . . . . M9-13Evacuating . . . . . . . . . . . . . . . . . M9-19Repair . . . . . . . . . . . . . . . . . . . M9-15Servicing . . . . . . . . . . . . . . . . . . M9-6Troubleshooting . . . . . . . . . . . . . . M9-22

Alternator . . . . . . . . . . . . . . . . . . . . D2-3Automatic Positive Locking Differential . . . M12-1Auxiliary Manifold . . . . . . . . . . . . . . . L7-2

BBackup Horn . . . . . . . . . . . . . . . . . . D4-5Backlash Adjustment, Ring and Pinion . . . G5-12Ball Stud Bearing . . . . . . . . . . . . . . . G3-5Battery

Charging Circuit . . . . . . . . . . . . . . . D2-5Charging Components . . . . . . . . . . . . D2-6Equalizer . . . . . . . . . . . . . . . . . . . D2-1

Bearing, Front Wheel Adjustment . . . . . . G3-2Bleeddown Solenoid Valve . . . . . . . . . . . L4-3Body Pads . . . . . . . . . . . . . . . . . . . B3-3Body Pivot Pins . . . . . . . . . . . . . . . . B3-2Body Position Indicator . . . . . . . . . . . . B3-4Body-Up Limit Switch Adjustment . . . . . . . B3-4Body Up Pin . . . . . . . . . . . . . . . . . . B3-3Brake, Parking . . . . . . . . . . . . . . . . . J7-1Brakes, Service

Accumulators . . . . . . . . . . . . . . . . . J2-2Bleeding (Front) . . . . . . . . . . . . . . . J5-4Bleeding (Rear) . . . . . . . . . . . . . . J6-13Brake Lock (Circuit) . . . . . . . . . . . . . D3-2Brake Lock Shuttle Valve . . . . . . . . . . J2-3Brake Lock Valve . . . . . . . . . . . . . . J2-3Caliper Repair . . . . . . . . . . . . . . . . J5-2Circuit . . . . . . . . . . . . . . . . . . . . . J2-1

B (cont’d)Brakes, Service (cont’d)

Disc (Front) . . . . . . . . . . . . . . . . . G3-2Disc Pack Thicknesses (Rear) . . . . . . . J6-12Lining Replacement . . . . . . . . . . . . . J5-1Manifold . . . . . . . . . . . . . . . . . . . J2-3Pressure Warning Switch . . . . . . . . . . J2-3Rear Brake Shuttle Valves . . . . . . . . . . J2-5Treadle Valve, Service . . . . . . . . . . . . J3-2Treadle Valve, Retarder . . . . . . . . . . J3-10

Burnishing, Park Brake . . . . . . . . . . . . J7-4Burnishing Procedures (Front) . . . . . . . . . J5-4

CCab . . . . . . . . . . . . . . . . . . . . . . N2-1

Heater . . . . . . . . . . . . . . . . . . . . N4-4Calipers, Front . . . . . . . . . . . . . . . . J5-1Carrier Bearing . . . . . . . . . . . . . . . G5-12Cautions and Warnings . . . . . . . . . . . . A4-1Charts

Metric Conversions . . . . . . . . . . . . . A5-1Standard Torques . . . . . . . . . . . . . . A5-1

Check Valves, Hoist Circuit . . . L7-2, L10-9, L10-10Circuits (Electric)

Air Conditioner . . . . . . . . . . . . . . . D3-6Auto/Manual (Transmission) . . . . . . . . D3-2Backup Horn . . . . . . . . . . . . . . . . D4-5Battery, Charging . . . . . . . . . . . . D2-3, 4-3Brake Lock . . . . . . . . . . . . . . . . . D3-2Control Power . . . . . . . . . . . . . . . D4-5Gauge & Tachometer . . . . . . . . . . . . D3-3Heater . . . . . . . . . . . . . . . . . . . D3-7Hoist Control . . . . . . . . . . . . . . . . D3-5Hoist Interlock . . . . . . . . . . . . . . . D4-5Hourmeter . . . . . . . . . . . . . . . . . D3-3Indicator, Warning Light . . . . . . . . . . D3-3Light . . . . . . . . . . . . . . . . . . . . D3-6Speedometer . . . . . . . . . . . . . . . . D3-3Starter . . . . . . . . . . . . . . . . D3-8, D4-5Transmission Control . . . . . . . . . . . . D4-1Windshield Wiper . . . . . . . . . . . . . . D3-1

Controls, Operator . . . . . . . . . . . . . . N5-1Cooling System . . . . . . . . . . . . . . . C3-1

Q01014 9/90 Alphabetical Index Q1-1

DDifferential . . . . . . . . . . . . . . . G5-3, G5-5

Automatic Positive Locking Differential . . M12-1Deck Structure . . . . . . . . . . . . . B2-1, N2-3Dump Body . . . . . . . . . . . . . . . . . . . B3-1

EElectrical Schematic . . . . . . . . . . . Section RElectrical Supply System . . . . . . . . . . . D2-1Element, Washing . . . . . . . . . . . . . . . C5-3Emergency Apply Valve . . . . . . . . . . . J2-3Engine . . . . . . . . . . . . . . . . . . . . C4-1

Oil Pressure Switch . . . . . . . . . . . . . D3-3Shut-Down Circuit . . . . . . . . . . . . . . D3-6

FFilter Air

Cleaning . . . . . . . . . . . . . . . . . . . C5-3Replacement . . . . . . . . . . . . . . . . C5-1

Final Drive . . . . . . . . . . . . . . . . . . G5-1Final Drive Driveline . . . . . . . . . . . . . . F5-1Final Drive Planetaries & Wheel Hub . . . . . G6-1Floating Ring Seal . . . . . . . . . . . . . . J6-7

Seal Carrier Dimension . . . . . . . . . . . . J6-3Front Wheel Hub & Spindles . . . . . . . . . G3-1Fuel Tank . . . . . . . . . . . . . . . . . . . B4-1

GGauges . . . . . . . . . . . . . . . . . . . . N5-1Gauge, Circuit . . . . . . . . . . . . . . . . D3-2Grille & Hood . . . . . . . . . . . . . . . . . C3-2

HHeat Exchanger . . . . . . . . . . . . . . . . C3-4Heater Circuit . . . . . . . . . . . . . . . . . D3-6Heater, Cab . . . . . . . . . . . . . . . . . . N4-4

Water Control Valve . . . . . . . . . . . . . N4-4Hoist Auxiliary Manifold . . . . . . . . . . . . L7-2Hoist Circuit . . . . . . . . . . . . . . . . . . L8-1Hoist Circuit Checkouts . . . . . . . . . . . L10-6Hoist Circuit Pressures . . . . . . . . . . . . L10-7Hoist Circuit Operation . . . . . . . . . . . . . L7-1Hoist Cylinder . . . . . . . . . . . . . . . . . L8-4Hoist Overcenter Valve . . . . . . . . . . . . L7-2Hoist Pump . . . . . . . . . . . . . . . . . . . L3-1Hoist Valve . . . . . . . . . . . . . . . . . . . L8-1Hoist Valve Pilot Pressure . . . . . . . . . . L10-6Horn Circuit . . . . . . . . . . . . . . . . . . D3-1Hourmeter/Tachometer Circuit . . . . . . . . . D3-3Hot Start . . . . . . . . . . . . . . . . . . . M7-1

H (cont’d)Hub, Front Wheel . . . . . . . . . . . . . . . G3-1HYDRAIR® Suspension

Charging . . . . . . . . . . . . . . . . . . . H4-1Front . . . . . . . . . . . . . . . . . . . . . H2-1Rear . . . . . . . . . . . . . . . . . . . . . H3-1Spherical Bearing (Rear) . . . . . . . . . . H3-4

HydraulicCircuit Description . . . . . . . . . . . . . . L2-1Diagram . . . . . . . . . . Schematics, Section RFilter Pressure Switch . . . . . . . . . . . . L3-12Hydraulic Filter(s) . . . . . . . . . . . . . . L3-10Pump Specifications . . . . . . . . . . . . L6-21Steering Brake Pump Repair . . . . . . . . L6-7Steering Circuit . . . . . . . . . . . . . . . L4-1System . . . . . . . . . . . . . . . . . . . L2-1Tank . . . . . . . . . . . . . . . . . . . . . L3-9

Breathers . . . . . . . . . . . . . . . . . L3-10

IIndicator Light Circuit . . . . . . . . . . . . . D3-3Instrument Panel . . . . . . . . . . . . . . . N5-1

KKeyswitch . . . . . . . . . . . . . . . . . . . D4-6

LLight Circuit . . . . . . . . . . . . . . . . . . D3-6Low Brake Pressure Detection Module . . . . J3-1Low Pressure Sensing Valve . . . . . . . . . J2-2Lubrication . . . . . . . . . . . . . . . . . . . P2-1

MManifold, Brake . . . . . . . . . . . . . . . . J3-1Manifold, Stop Light and Tee . . . . . . . . . J2-5Manual/Auto Maintenance Switch . . . . . . . D4-5Metric Conversion Chart . . . . . . . . . . . . A5-1

NNitrogen Charging, Accumulators, . . . . . . . L6-1Nitrogen Charging, Suspensions . . . . . . . H4-3

Q1-2 Alphabetical Index Q01014 9/90

OOil Cooled Disc Brakes (Rear) . . . . . . . . . J6-1

Bleeding Procedure (Rear) . . . . . . . . . J6-13Brake Disc Wear Indicator . . . . . . . . . J6-14Brake Circuit . . . . . . . . . . . . . . . . . J2-1Circuit Check-Out Procedure . . . . . . . . . J4-1Circuit Component Service . . . . . . . . . . J3-1Diagram (Hydraulic) . . . Schematics, Section RDisc Pack Specifications . . . . . . . . . . J6-12Heat Exchanger . . . . . . . . . . . . . . . C3-4Oil Temperature Warning Switch . . . . . . . D3-5Piston . . . . . . . . . . . . . . . . . . . . . J6-6Return Spring Specifications . . . . . . . . . J6-6

Oil Cooled Disc Brakes (cont’d)Seal Assembly/Installation . . . . . . . . . . J6-7

Oil Pressure Gauge, (Engine) . . . . . . . . . D3-3Oil Pressure Sensor . . . . . . . . . . . . . . D3-3Oil Pressure Switch . . . . . . . . . . . . . . D3-3Operators Cab . . . . . . . . . . . . . . . . . N2-1

Seat . . . . . . . . . . . . . . . . . . . . . N4-1Operator Controls . . . . . . . . . . . . . . . N5-1

Retarder Operation . . . . . . . . . . . . . . N5-8Throttle Pedal . . . . . . . . . . . . . . . N5-13

PPanel, Instrument . . . . . . . . . . . . . . . N5-4Panhard Rod Bearing . . . . . . . . . . . . G4-3Park Brake . . . . . . . . . . . . . . . . . . . J7-1Park Brake Actuator . . . . . . . . . . . . . . J7-2Park Brake Circuit . . . . . . . . . . . . . . . D3-2Parking Brake-Hoist Valve Circuit . . . . . . . L7-2Power Down Pressure . . . . . . . . . . . . L10-7Power Take-Off . . . . . . . . . . . . . . . . F4-1Pressure Relief Valve, Adjusting . . . . . . . L10-7Pump, Hoist . . . . . . . . . . . . . . . . . . L3-1Pump, Steering . . . . . . . . . . . . . . . . . L4-1

QQuick Fuel Systems . . . . . . . . . . . . . M5-1

RRadiator . . . . . . . . . . . . . . . . . . . . C3-1Radiator Shutters . . . . . . . . . . . . . . M19-1Relay Box . . . . . . . . . . . . . . . . . . . D4-6Rear Brake Shuttle Valves . . . . . . . . . . . J2-5Rear Wet Disc Brakes . . . . . . . . . . . . J6-1Retarder Operation . . . . . . . . . . . . . . N5-8Retarder Treadle Valve . . . . . . . . . . . . J3-10Return Hydraulic Filter(s) . . . . . . . . . . . L3-10

SSafety Rules . . . . . . . . . . . . . . . . . A3-1Seat, Operators . . . . . . . . . . . . . . . . N4-1Service Brake, Treadle Valve . . . . . . . . . J3-2Shutters, Radiator . . . . . . . . . . . . . . M19-1Shuttle Valves, Rear Brake . . . . . . . . . J2-5Solenoid, Start . . . . . . . . . . . . . . . . D4-6Special Tools . . . . . . . . . . . . . . . . . M8-1Specifications . . . . . . . . . . . . . . . . . A2-1Speedometer . . . . . . . . . . . . . . . . . D3-3Spider Gear . . . . . . . . . . . . . . . . . . G5-8Spindle . . . . . . . . . . . . . . . . . . . . G3-1Start Solenoid . . . . . . . . . . . . . . . . . D4-6Starter, 24V . . . . . . . . . . . . . . . . . . D3-8Steering Bleeddown Circuit . . . . . . . . . . D3-5Steering Circuit . . . . . . . . . . . . . . . . L4-1Steering Control Valve . . . . . . . . . . . . L5-1Steering Cylinders . . . . . . . . . . . . . . L4-3Steering Pressure Switch . . . . . . . . . . . L4-3Structures

Body Pads . . . . . . . . . . . . . . . . . . B2-1Body Pivot Pins . . . . . . . . . . . . . . . B2-1Body Position Indicatior . . . . . . . . . . . B3-4Body-Up Pin . . . . . . . . . . . . . . . . . B3-3Cowl and Hood . . . . . . . . . . . . . . . B2-1Decks . . . . . . . . . . . . . . . . . . . . B2-1Dump Body . . . . . . . . . . . . . . . . . B3-1Fuel Tank . . . . . . . . . . . . . . . . . . B4-1Liner Plates/Body Repair . . . . . . . . . . B3-4Rock Ejectors . . . . . . . . . . . . . . . . B3-4

Switch, Body-Up Limit . . . . . . . . . B3-4, D3-5Switch, Brake Pressure Warning . . . . . . . J2-5System, Electrical . . . . . . . . . . . . . . . D2-1

Q01014 9/90 Alphabetical Index Q1-3

TTachometer Circuit . . . . . . . . . . . . . . D3-3Tank, Hydraulic . . . . . . . . . . . . . . . . L3-9Tank, Fuel . . . . . . . . . . . . . . . . . . B4-1Throttle Control Pedal . . . . . . . . . . . . N5-13Tires and Rims . . . . . . . . . . . . . . . . G2-1

Front . . . . . . . . . . . . . . . . . . . . G2-3Rear . . . . . . . . . . . . . . . . . . . . . G2-4Removal . . . . . . . . . . . . . . . . . . . G2-2Tire Matching . . . . . . . . . . . . . . . . G2-5

Toe-In Adjustment . . . . . . . . . . . . . . G3-6Torque Chart, Standard . . . . . . . . . . . . A5-1Transmission . . . . . . . . . . . . . . . . . . F2-1Transmission Circuit Components . . . . . . D4-6

Check Light . . . . . . . . . . . . . . . . . D4-1"Do Not Shift" Light . . . . . . . . . . . . . D4-1

Transmission Control Circuits . . . . . . . . D4-3Transmission Drive Line . . . . . . . . . . . F5-1Transmission Filter . . . . . . . . . . . . . . F2-4Transmission Heat Exchanger . . . . . . . . F3-1Troubleshooting

Air Conditioning . . . . . . . . . . . . . . M9-22Brake System . . . . . . . . . . . . . . . . J2-5Hydraulic System . . . . . . . . . . . . . . L10-8

VValves

Accumulator Charging Valve . . . . . . . . L6-4Accumulator Discharging Valve . . . . . . . J2-2Accumulator Shuttle Valve . . . . . . . . . . J2-2Auxiliary Valve Adjustment . . . . . . . . L10-6Brake Lock Shuttle Valve . . . . . . . . . . J2-3Brake Lock Solenoid Valve . . . . . . . . . J2-3Brake Manifold Shuttle Valve . . . . . . . . J2-3Check Valves, Hoist Circuit . L7-2, L10-9, L10-10Emergency Apply Valve . . . . . . . . . . . J2-3Hoist Valve . . . . . . . . . . . . . . . . . . L8-1Low-Pressure Sensing Shuttle . . . . . . . . J2-2Overcenter Valve . . . . . . . . . . . . . . L7-2Pressure Reducing Valve . . . . . . . . . . L7-2Retarder Treadle Valve . . . . . . . . . . J3-10Service Brake Treadle Valve . . . . . . . . J3-2Shuttle Valves

Accumulator Shuttle Valve . . . . . . . . . J2-2Brake Lock Shuttle Valve . . . . . . . . . J2-3Rear Brake Shuttle Valves . . . . . . . . J2-5Service Brake/Retarder Shuttle Valve . . . J2-4

Steering Bleeddown Solenoid Valve . . . . . D3-5Steering Control Valve . . . . . . . . . . . . L5-1

WWarning Lights . . . . . . . . . . . . . . D4-5, N5-9Warnings and Cautions . . . . . . . . . . . . A4-1Warning Light Circuit . . . . . . . . . . . . . D3-3Wet Disc Brakes, Rear . . . . . . . . . . . . J6-1Wheel Hub Removal, Rear . . . . . . . . . . G6-1Wheel Speed Disc Brake . . . . . . . . . . . J5-1Windshield Washer . . . . . . . . . . . . . . D3-1Windshield Wiper Circuit . . . . . . . . . . . D3-1

Q1-4 Alphabetical Index Q01014 9/90

SECTION R

SYSTEM SCHEMATICS

INDEX

ELECTRIC SCHEMATIC (3 Fold-Out Pages) . . . . . . . . . . . . . . . . . . . . . . . . . HE 403

HYDRAULIC SYSTEM SCHEMATIC (1 Fold-Out Page) . . . . . . . . . . . . . . . . . . . . HH 311(With Rexroth Steering/Brake Pump and Rear Oil-Cooled Disc Brakes)

ALLISON TRANSMISSION (CLT 5963/6063) HYDRAULIC SCHEMATIC . . . . . . . . AT 5/6-HO12

R01005 8/95 Schematics R1-1

NOTES

R1-2 Schematics R01005 8/95

betty panek

betty panek

betty panek

betty panek

betty panek

betty panek

betty panek

betty panek

betty panek

betty panek

Manual 210M

Documents

Transcript of Manual 210M