(DAIHATSUI TYPE SECTION

BEFORE RUNNING DAIHATSU DIESEL ENGINE 1 DL-20 SHEET 1

1. Read the following rules for correct and safe operation of Daihatsu Diesel Engines before use.

2. Engine specifications and separate assembly drawings shall have priority over this manual.

3. ln case of change in the fuel oil and/or in the working load, which is not shown in the specification, necessitated after delivery, some modification is necessary on the engine side.

For the following units and special specifications, see separata manuais:

Turbocharger

Hydraulic governor (Woodward, Diesel Kiki and others) Remote auto control unit and protective units

Automatic temperature control valves (for lubricating oil, cooling water, etc.) Reduction gears and operating units . . . . . . . . . . . . . . . . . . . Marine propulsion engne

Generator ............. : . . . . . . . . . . . . . . . . . . . . . . . . . Engine for generator

Heavy fuel oil system related parts . . . . . . . . . . . . . . . . . . . . When heavy fuel oil is used

Other units as per special specification

Contents of this manual are subject to change for improvement without notice.

IDAIHATSU) SECTION TYPE 2 SHEET DL-20

1

1. General Description of Engine The Daihatsu DL-20 Type Diesel Engine offers

excellent performance and durability with special design emphasis on simple and sturdy construc-tion, easy operation, compact size, light weight and high output.

Designed in accordance with various standards, rules and regulations (NK, AB and LR-), it has many applications as marine propulsion engine, auxiliary engine and stationary engine for power generation and power sources for various systems.

All the components parts are manufactured under the mass-production system and the strin-gent quality control system employed at Daihatsu plants to have complete interchangeability, and are available in enough quantities at ali times.

Output is at the flywheel end of the crankshaft. The opposite end is referred to as the front of the engine, where ali operation apparatus and gauges are arranged.

Cylinder numbers shall be 1, 2, 3 and so on, starting with the one locating at the front-most position.

DL-20 Type Diesel Engine comes in 6-cylinder models equipped with turbocharger and air-cooler. It is wide-ly adaptable to special specifications that it can easily be adapted to remate and automatic control systems and also to MO system setup.

DL-20 j A 1 87-6

GENERAL General Description of Engine

< Notation of types > (Example)

(6) DL (M) - 20 (L)(F) (S) ( 6) . . . . . . . . Number of cylinders DL (B) ...... Medium speed, vertical type (M) ....... Marine propulsion engine 20 -.-....... Cylinder bore (cm) (L) ........ Modified for reverse rotation (F) . . . . . . . . Modified for front end power

takeoff (S) ........ Modified for bottom installa-

tion sole plate design

Notes: 1) Rotating direction of engine when viewed from engine flywheel side, shall be defined as follows:

Clock wise rotation of flywheel: Normal rotation

Counterclockwise rotation of flywheel: Reverse rotation

2) Cylinder numbers shall be 1, 2, 3, and so on, as below.

Flywheel

CD@ FO

IDAIHATSUI

GENERAL TYPE SECTION 2 Cross-section DL-20 SHEET 2

1 DL-20 1 Z 1 84-3 1

IDAIHATSU) SECTION TYPE GENERAL 2 SHEET DL-20 Engine Specifications 3

Engine for generator and for general power unit Marine Propulsion engine Model

6DLB-20 6DL-20 6DLM-20

Type Vertical, water-cooled, direct-injection type, four-cycle diesel engine Number of 6 cylinders

Cylinder bore mm 200

Stroke mm 260

Engine speed rpm * * *

Output PS * * *

Rotating Clockwise as viewed from flywheel direction

Supercharger Exhaust gas turbocharger (with air-cooloer) Starting method Compressed air

Firing order 1 5-3-6-2 4

"' Length (A) 2645 ~ mm .:a "' ~ Width (!) s

(B) mm 1100 :e; Height (C) mm 1495 Weight kg 6700 6750

Notes: 1) The dimensions and weight of the engine shown above are of the engine proper only. 2) *Engine speed and output vary according specifications. Please fill them in at users.

i----------A------i

IDAIHATSUI GENERAL TYPE SECTION 2

Auxiliary Equipment DL-20 SHEET 4

E: Engine R: Engine room

Auxiliary equipment Type Place of Remarks installation

Turbocharger Exhaust gas turbocharger E VTR

Intercooler Fine tube E

Governar Hydraulic E

Fuel oil injection pump Bosch E ex

Fuel oil nozzle Bosch E TE

Fuel oil pump Gear or trochoid type Separately installed or driven by engine.

Lubricating oil pump Gear E With safety valve

Rocker arm lub. pump Trochoid type E With safety valve

Cooling water pump Centrifugai E (for jacket) Cooling water pump Centrifuga! R (for cooler)

Nozzle cooiing oil pump Gear Separately installed or driven by engine when heavy fuel oil is used.

Lubricating oil cooler Multi-tubular R

Fresh water cooler Multi-tubular R (for jacket) Nozzle cooling oil cooler Fin R When heavy fuel oil is used.

High-precision fuel oil filter Backwash type R Not required, depending on specifications

Fuel oil filter (engine inlet) Notche wire or Laminate E

Lubricatng ol filter Notch wire E

Governor lubricating oil filter Notch wire E When SG2 or PSG governar used.

Rocker arm lubricating filter Laminate E

Nozzle cooling oil filter Laminate E When heavy fuel oil is used.

Full-flow fresh water filter Y-type strainer R (for jacket) Rockerarmlubricatingtank E 10 R Leaked oil tank E SR

Notes: 1) Refer to separate assembly drawings for specifications. 2) Descriptions in this table are subject to change according to specifications.

DL-20 1 D l so-9 1

(DAIHATSUI SECTION

3 SHEET

1

Intake valve

Exhaust valve

Starting rotary valve

TYPE

DL-20

Item

Open (before T.D.C.)

Close (after B.D.C.)

Clearnace (A)

Open (before B.D.C.)

Close (after T.D.C.)

Clearance (A)

Open (after T.D.C.)

Close (after T.D.C.)

Fuel nozzle njection pressure

Maximum explosion pressure

Pressure of cylinder safety valve (Relief pressure)

ENGINE AD'"1USTMENT STANDARDS Engine Adjustment Table

Adjustment value (Design value)

75

35

0.4mm

50

60

0.4mm

o

125

300 kg/cm2

135 kg/cm2

170 kg/cm2

Remarks

B

1) Valve clearance is with engine cold. 2) should be set at "O" prior to the adjust-

ment of

Refer to the factory operation test result as the values vary wth individual engine specifications and output.

Note: These values vary with each engine. For actual values, refer to engine nameplate and operation tesf result sheet.

DL-20 1A1 87-6

IDAIHATSUI ENGINE AD~USTMENT STANDARDS TYPE SECTION 3

Operating Specifications DL-20 SHEET 2

Alarm Setting Item Design Value (Emergency stop Remarks

Setting)

lntake air According to turbocharger specifications

Starting air 15 - 30 15

Fuel oil 2.0 - 3.0 Static pressure of tank head *(5.0-6.0) should be considered.

Pressure Lubricating oil 4.0 - 5.0 2.5(2.0) (kg/cm2 ) Rocker arm lubricating oil 0.6,..,,, 1.2 0.3

Cooling Jacket 2.5 - 3.5 Tank head and externai piping water Coo ler conditions should be considered.

Nozzle coolant pressure L0-3.0 Specified for opration with heavy fuel oil. Intake air Engine inlet 4Q,..,,, 50

Cylinder outlet 480 Exhaust gas Turbocharger inlet 580 According to turbocharger

Turbocharger outlet 480 specifications

Fuel oil Engine inlet 65 sec. RW No.1 80 sec. RW No.l Viscosities are for heavy fuel oil. (14 cst) (18 cst) Engine inlet 40-60 65

Tem per- Lubricating ature oil Engine outlet 70 (C) (inlet of LO cooler)

Engine inlet 70 ln case of inlet control system Jacket line Engine outlet 75 85 (90) ln case of outlet control system (fresh

Cooling water) Valve seat cool- 80 water ing water outlet

Cooler line Engine inlet 24- 32 (sea water)

Notes: l) Lower limit values are used for pressure settings; upper limit values are used for temperature settings for alarm and emergency stop.

2) Thermometer for measuring temperature of exhaust gas at turbocharger inlet is special specification.

3) Whether or not alarm and emergency stopping

IDAIHATSUI SECTION TYPE ENGINE ADJUSTMENT STANDARDS 3 SHEET DL-20 Capacity of Lubricating Oil and Cooling Water 3

(Unit: Q)

Item Capacity Remarks

Engine 10

Lubricating oil cooler 60 ...... A 50 ...... B A ... 9.7m2

, B .... 7.3m2

35 ...... e e ... 6.3m2

Turbocharger 1.5 ...... A 0.7 ...... B A ................ VTR161 B ................ VTR160

Lubricating oil Lubricating oil tank 1.0~2.0Q/PS is recommended. According to fuel oil porperty and bath engine specifications.

Rocker arm oil tank 10

Hydraulic govenor 1.3 ...... A 1.5 ...... B A ................ RHD 6 (Sump type) B ................ UG-8

Engine 100

Lubricating oil cooler 55 ...... A 45 ...... B A ... 9.7m2

, B .... 7.3m2

15 ...... e e ... 6.3m2

Cooling water Turbocharger 11 ..... A 8 ....... B A ............... VTR161 B ............... VTR160

Air cooler 15 ..... A ...... B A ................. DK30

11 B .......... ....... DK27

Note: Capacity in ths table may dffer accordng to specifications.

DL-20 1 A l a7-6

IDAIHATSUI ENGINE AD~USTMENT STANDARDS TYPE SECTION 3

Tightening Torque Table DL-20 SHEET 4

Names of bolts and nuts Size Width across Tightening torque flats (mm) (kg m) Cylinder head tightening nut M30x2.0 41 75

Main bearing mounting nut M30x2.0 41 75

Tie bolt M27 x2.0 41 40

Connecting rod bolt M30x2.0 41 A torque 35 kgm + 50 ** lB tornue 95 bml

Balance weight mounting bolt M30x2.0 46 60

Flywheel mounting bolt M33 X 3.0 50 70

Fuel cam tightening nut M72X1.5 - 80 **

Main Camshaft drive gear tightening nut M42 X 1.5 65 100 bolts Nozzle holder guide clamp nut M48 X 1.5 33 18 and nuts Nozzle ho,lder tightening nut Ml6 X 2.0 24 7

Fuel nozzle mounting cap nut M28 X 1.5 27 10-13 *

Rocker arm shaft holder tightening nut (1) M22x2.5 32 25 Rocker arm shaft holder tightening nut (2) Ml4x2.0 22 7 ldle gear shaft mounting bolt Ml6x2.0 24 17

Delivery valve holder, F.0. pump M45 x3.0 46 42-45 *

ldle gear shaft oiling bolt M30x2.0 41 60 *

ldle gear shaft retaining bolt Ml2X1.75 19 8 MlOx l.5 17 1.5-2

Ml2 X 1.75 19 3-4 General bolts and nuts

Ml4 X 2.0 22 3.5-5

Ml6x2.0 24 5-7

Notes: 1) Main bolts and nuts marked * should be tightened according to the following specifications. Connecting rod bolt . . . . . . . . . . . . . . . . . . . Section 7, Sheet 13, 14 Fuel cam tightening nut . . . . . . . . . . . . . . . Section 7, Sheet 20, 21

2) Nuts and bolts must be tightened in a diagonally alternating sequence. 3) Be sure to check for loose cylinder head t.ightening nuts and connecting rod bolts after a certain period

of operation. Refer to Section 6 for inspection frequency. 4) Anti-seizure agent should be applied before tightening to bolts seats and threads used for the parts

around the exhaust pipe, which are to be subject to high temperature. 5) Torque wrenches used for tightening shall be inspected periodically. 6) Anti-seizure agent (MOLYKOTE 1000 Spray type) should be applied before tightening to the seats

and threads of tightening bolts and nuts marked with;:.

DL-20 1 F J so-9

IDAIHATSU) SECTION TYPE ENGINE ADJUSTMENT STANDARDS 3 SHEET DL-20 Clearance and Wear Limit 7

Part Schematic drawing Size Standard Wear and repair Remarks and . clearance limit remedy

t; Tappet and tappet A=45 a =O.O 3-0.0 8 0.25 Replace the one P. guide wommore. P. s Llt >i 'O i:: Camshaft bearing ~ A=60 a=0.04-0.11 0.2 Replace bearing. '!;i ii ~ u Camshaft thrust b=0.15 Replace thrust bearing 0.45 bearing. !d

Idle gear shaft and e~ A=60 a=O.O 3-0.12 0.3 Replace bearing. ., bearing Cl) Cl) .$ . E-< Backlash. b=0.2 - 0.3 0.5 Replace gear. te ~ =~ Backlash b=0.3-0.6 0.8 Replace gear OIOO

P. A~ e IOll:::: Mouse ring and i:: P. A=105 a=0.25-0. 28 O. 7 5 :g ~ impeller o

MAINTENANCE Dimensions of Disassembly and Weights of Main

Detail "A".

( lVTR160

1674

Ml2X 1.75

t-

"' 8 ""'

~~

CRANK SHAFT CENTER

Weights of main parts

Cylinder head, complete

Piston and connecting rod, complete

Cylinder liner Camshaft, complete Lubricating oil pump

Turbocharger

Intercooler

::; Q ....

"' "'

"' ....

;:'.;

o

"' ;";

"" !!l -

Aluminum FCD

VTR 160 VTR 161

DK30 DK 27

(DAIHATSU) TYPE SECTION 3

Parts DL-20 SHEET 8

NO.I CYL. CENTER

725

Unit kg

6DL-20 78 55 58 52 77

27

160 204 240 220

1 DL-20 1 A 1 86-41

IDAIHATSUI SECTION TYPE GENERAL CONSTRUCTION 4 SHEET DL-20 Sole plate, Frame and Related Parts, Cylinder Head

1 and Related Parts

1. Sole Plate, Frame and Related Parts

(1} Sole Plate and Frame Sole plate and frame, of one-piece construction

respectively, are so designed to be sufficiently rigid yet lightweight and cause lease stress concentra-tion.

A water-jacket is formed between upper part of frame and cylinder liner. Crankcase is between lower part of frame and sole plate.

A large inspection hole is provided for each cyl-inder on the side face. of the crankcase to give access for inspection and overhaul of main bearing, connecting rod and the like main working parts.

Bach of the inspection windows is equipped with a safety valve, and a mist-gas outlet hole is provided at the rear part of the frame.

Standard design of the sole plate is a flat bot-tom type which does not store oil, but a ship-bottom type sole plate ( equipped with oil pan) which can store mininum quantity of oil may be available for special specification. Even in the case of the ship-bottom type sole plate, (not to men-tion the case where the standard flat-bottom type sole plate is used) a separate lubricating oil tank must be provided to store enough quantity of oil for initial filling of oil to every part of the engine.

Sole plate and trame

(2} Cylinder liner

Main bearing cap

Flat-bottom type sole plate

Cylinder liner is made of high grade cast iron material and its inner surface is super precision finished by honing. It is a so-called wet type liner forming a water jacket between the inner wall of the frame.

DL-20 1 Z 1 84-3 1

Flange part of the liner is firmly secured via packing along with the cylinder head to the frame to prevent leakage of water and exhal,lst gas. O ring is inserted to t:O.e lower periphery part of the cylinder liner to prevent leakage of water into the crankcase while providing relief for thermal expan-sion of the liner.

(3) Main bearing Main bearing cap is made of nodular cast iron

material and is set in the sole plate to be fixed to the frame with two metal cap bolts. It is boring finished together with the sole plate to form metal housing.

Main bearing

Main bearing is of a two-piece split type, in which aluminum alloy metal is deposited on mild steel backing to form a thin wall complete bearing. Although it is designed to be fully interchangeable, it must be replaced when necessary in a set of the upper and the lower halves without exception.

Catch is provided at asymmetric position on each half of the bearing so that the bearing is set in place without rotating along with the shaft and that each half will be set correctly.

The main bearing provided at the flywheel end serves concurren tly as a thrust bearing to the crankshaft, with a thrust bearing being inserted in the space between the side of the main bearing house and the crankshaft.

2. Cylinder Head and Related Parts (1) Cylinder head

The cylinder head is made to have sufficient rigidity using high grade cast iron material and designed to form effective cooling jackets and highly efficient intake and exhaust passage. At its center is the fuel nozzle, around which intake and exhaust valves, rocker arm and rocker arm shaft holder, starting air valve, cylinder safety valve and indicator valve are provided.

IDAIHATSUI GENERAL CONSTRUCTION TYPE SECTION 4

Cylinder Head and Related Parts, Piston, Connecting DL-20 SHEET Rod and Related Parts

A semi-enclosed system is employed for the automatc lubrication of the area around the rocker arm on the top face of the cylinder head, makng it splash-proof by means of the cylinder head cover.

(2) lntake and exhaust valves The intake and exhaust valves are of poppet

valve type equipped with valve rotator. They are so designed that an uniform thermal load can be obtained by rotating the valves.

The guide and the seat of both intake and exhaust valves are pressure-fit to the cylinder head.

Water-cooled design is employed for the ex-haust valve seat in consideration of use of heavy fuel oil.

The double-coil type valve spring is supported with the cylinder head at its lower end, while at its upper end split type cotter is inserted nesting on the valve rotator, which serves to hold the spring in place while securing the valve in position.

Valve rotator

lntake valve Exhaust valve

(3) Cylinder safety valve and indicator valve The cylinder safety valve opens automatically if

the explosion pressure inside the cylinder (Pmax) exceeds the normal value to prevent the mechani-cal stress exerted on major structural parts of the engine from becoming excessively great while issu-ing an alarm for abnormality in the condition of combustion. ln compliance with the ship classifi-cation rules, the cylinder safety valve isso adjusted th.t it will open automatically in case of a rise in the explosion pressure within 1.4 times the maxrnum explosion pressure.

The indicator valve consistues a unit together with the cylinder safety valve and used when de-tecting combustion pressure via a pressure indica-tor connected or for aiding in tuming of the en-gine by relieving the compression pressure.

2

3. Piston, Connecting Roei and Related Parts

(1) Piston, Piston Pin and Piston Ring The piston is available in solid aluminum cast-

ing type and solid nodular ron casting type for selection according to the property of the fuel oil used.

Cocktail shaker method on nozzle jet is em-ployed for cooling the piston, and the construc-tion of the piston having coolant passage inside makes it resistant to high temperature and high pressure.

Three piston rings are fitted to the upper part of the piston; of which the top ring and the second ring are chromium-plated to minimize wear on the liner and the rings.

The oil ring with a high tension has a coil to effectively shut out the upflow of lubricating oil.

The piston pin made of chrome-molybdenum steel material is grinding finished after hardening. The full-floating system employed for the piston boss hole and the piston pin bearing, which allows rotation in either . drection inside these parts, effectively prevents local wear because of the constant change in the pressure bearing surface and the sliding surface.

Piston ring

Retaining ring

Oil ring

Aluminum piston FCD piston

. Piston

(2) Connecting rod and crank pin bearing The connecting rod is made of solid forged

steel to have high rigidity. Precisely machined piston pin bearing hole is bored at its small end and a crank pin shaft bole is provided at its large end. The trunk portion of the connecting rod having 1-shaped cross section has an oil hole for lubrication of the piston pin bearing at its central part. The large end is split slantwise into two with serrated surfaces, and is fixed frmly by means of connecting rod bolts.

DL-20 1 A 1 87-6

(DAIHATSUI SECTION TYPE GENERAL CONSTRUCTION 4 SHEET DL-20 Piston, Connecting Rod and Related Parts,

3 Valve Operating Mechanism, Crankshaft and Flywheel

The piston pin bearing press-fit in the small end consists of lead bronze bearing metal deposited on the forged steel back-up metal of cylindrcal shape. The crank pn bearing is of thn-shell type consisting of aluminum alloy bearng metal depos-ited by non-solderng method on the two-piece split type forged steel back-up metal, havng the sarne feature as possessed by the main bearing.

The connectng rod bolts are made of special steel material to have enough tightening force and to be sufficently resistant to the force of inertia repeatedly exerted during operation.

Connecting rod

4. Valve Operating Mechanism The tappet which follows the intake/exhaust

cam is of roller tappet type and slides along the tappet guide seated in the tappet hole provided on the frame. The tappet is provided with a push rod seat, and a push rod protectve sheath is pro-vided between the tappet guide and the cylinder head.

The rocker arm recieves the vertical movement of the tappet controlled by the intake/exhaust cam via the push rod and performs the rocking motion around the rocker arm shaft to open and close the intake and the exhaust valves.

The valve clearance is necessary so that the valve will sit on the seat securely even when the valve stem and push rod expand with heat during operation. Thus an adjusting screw is provided on the rocker arm.

DL-20 1A1 87-6 1

. Rocker arm shaft Rocker ann adjusting screw Rocker arm

Push rod protective sheath

Pushrod

Tappet guide

Tappet

Intake/exhaust cam

Valve operating mechanism

5. Crankshaft and Flywheel The crankshaft is of one-piece constructon

using high grade RR forged steel and designed to have a hgh rigidity with greater shaft diameter n consideration of the pressure to be exerted on the bearing and torsonal vibration that may occur n each of the rotational frequencies durng opera-tion, Their dimensions are made to meet the re-quirements prescribed in different shp classifica-tion Rules and Regulations.

The rear end of the crankshaft constitutes the power output shaft coupling, to whch the fly-wheel is mounted via reamer bolts.

If required by the special specifications, power take~ff from the front of the crankshaft is possible.

Roles are provded along the perphery of the flywheel to faciltate for turning bynserting turn-ng bar in these holes.

ln the case of marne propulsion engine, engine torque is transmitted to the propeller shaft via the shock-absorbing rubber. For more detail on ths respect, please refer to the Operation Manual for Reduction Gear supplied in a separate volume.

lDAIHATSUI GENERAL CONSTRUCTION TYPE SECTION 4

Camshaft and Cam, Timing Gear, Governar and DL-20 SHEET Fuel Contrai Devices

6. Camshaft and Cam The camshaft made of carbon steel material is

driven, at 1/2 crankshaft rotation, by the crank-shaft via the timing gears.

The cam bearing is of a complete thin-wall type bearing, consisting of the white bearing metal de-posited thinly over the surface of the thin forged steel shell of semi-circular cross section, having the sarne feature as that of the main bearing and the crank pin bearing used in this engine.

Thrust of the camshaft is received via the cam-shaft retaining ring at No.1 cylinder side.

Both the intake/exhaust cam and the fuel cam ~re made of special steel material with their roller fit-up surfaces having been winding finished after hardening.

While the intake/exhaust cam is fixed to the camshaft by means of a key, the fuel cam is made to rotate around the camshaft to allow fine adjust-ment of fuel injection timing.

The camshaft is mounted to the frame via the camshaft bearing provided for each section wall in the frame and fixed with lubrication bolts.

Camshaft bearing cap is divided into two halves to be fixed together with reamer bolts.

Where there is a limitation to the space needed for extracting camshaft for maintenance, it is possible by special specification to employ a split camshaft construction divided at its central part.

Tightening nut .~hmlingwt

~.~ ~" Camshaft

Fuelcam

Fuel cam

Lubrication bolt

Bearlng metal

Camshaft

Cam bearing

4

7. Timing Gear The timing gear mechanism transmits the

driving force imparted by the crank gear to drive the cam gear via the idle gear.

Each of the gears is grinding finished after hard-ened by carburizing to improve wear resistance. The crank gear is mounted at the front part of the crankshaft and fixed by shrinkage fit.

Crank: gear

Timinggear

8. Governar and Fuel Contrai Devices The governor is of the hydraulic type. For details of its construction and correct

handling, refer to the separate Manual. The force of the governor used to control the

operation of the engine is transmitted to the rack of the fuel injection purnp from the common rod via the link spring fitted to the connecting rod.

The common rod is fitted with shock absorbing springs for each of the cylinders, so that even if the rack for a certain cylinder should fail to move due to sticking during operation, other cylinders are made to move in the direction reducing the rate of fuel oil supplied.

It can be started, run and stopped by operating the stop lever. ln the case of a remote-control or self-starting type engine, the stop lever is normally located at the RUN position and interlocked with the pneumatic control piston at the time of start-ing so that thrusting motion of rack is relieved.

Various kinds of sensors are provided around the common rod, including the rack stopper and other safeguard

IDAIHATSUI SECTION TYPE GENERAL CONSTRUCTION 4 SHEET DL-20 Rocker Arm Lubricating Oil System and Related Parts 9

15. Rocker Arm Lubricating Oil System and Related Parts

1. Since the oil which lubricates the rocker arm is apt t'O become dirty because of exhaust gas or fuel oil contamination, the line is made independent and separate from the line for system oil. As shown in the following rocker arm lubrication system diagram, lubricating oil pressured-fed by the rocker arm lubrication pump, after lubricat-ing the rocker arm, drops onto the top face of the cylinder head and is recovered via the return main pipe to the rocker arm lubricating oil tank.

However, some oil returns directly to the rocker arm lubricating oil tank from the oil pressure regulating valve at the end of the supply oil main pipe.

The trochid type rocker arm lubrication pump is fitted with a safety valve and driven by the gear at the front of the camshaft.

The rocker arm lubricating oil filter is of the metal lamination type; the pressure regulating valve is installed at the end of the supply oil main pipe to control the pressure inside the main pipe.

The rocker arm fbricating oil tank is located at the rear of the engine.

Lubricating oi! filter

Rocker arm lubricating oi! pump

:Retum main ppe

Rocker arm lubricating oil tank

2. ln Iand/emergency spec. engines, rocker arm and system oil Iubrication are by sarne system.

Supply oi! main pipe Pressure regulating valve

Oil flow regulating valve

Rocker Arm Lubricating Oil system Diagram (Separate type)

IDAIHATSU) GENERAL CONSTRUCTION TVPE SECTION 4

Cooling Water System and Related Parts DL-20 SHEET 1 o

16. Cooling Water System and Related Parts

The cooling water system differs according to the grade of fuel oil used and the operating specifications of the engine. Typical water cooling system setup is shown below.

The water cooling system shown in this diagram is divided into twQ lines; the jacket line and the cooler line. Thejacket line is so constructed that the cooling water in the line is bypassed to branch off from the cylinder jacket line to cool the turbocharger.

Standard cooling media used for the jacket tine is fresh water and that for the cooler tine is sea water.

The cooling water adjustment flange perrnits even distribution of cooling water to each cylinder. The adjustment flange is designed so that it is not fully closed even if it is set at the fully shut position. The fully open position is marked "0" on the adjustrnent flange, while the fully shut position is marked "S".

Fresh water head tank

. Air release valve

Fresh water pump .for jacket line

The tine marked with * is added for the specifi-cation of heavy fuel oil, where water-cooling of the exhaust valve seat is employed. To prevent blockage of the flowline in the exhaust valve seat cooling system, a full-flow strainer (installed on the ship's hull) is provided at the intake side of the cooling water pump.

Adjustment flange

Cooling Water Adjustment Flange

Jacket line outlet main pipe

* Valve seat outlet main pipe

Jacket line inlet main pipe

Turbochargeri----

Seawater pump for cooler line

Intercooler * Applies for engines operated on

heavy fuel oils

Lubricating oi! cooler

Cooling Water System Diagram

1 oL-20 1 e 1 so-s I

(DAIHATSUJ SECTION TYPE GENERAL CONSTRUCTION 4 SHEET DL-20 Nozzle Cooling Oil System and Related Parts 1 1

17. Nozzle Cooling Oil System and Related Parts

(For engine operated on heavy fuel oil) Either grade Diesel fuel oi! or thermal oi! is used as

nozzle cooling oi!, depending on the specifications. An example nozzle cooling oi! system is shown below.

Pressure-fed cooling oil from the nozzle cooling oil pump cools the nozzle and then returned to the cooling oil tank.

Part of the oil is directly returned to the return main pipe through the pressure regulating valve of the return main pipe.

When grade Diesel fuel oi! is used for this purpose, the tank containing the oi! may commonly be used as the nozzle cooling oi! tank with the nozzle cooling oi! cooler omitted in some cases.

Pressure regulating valve (adjustable)

Automatic temperature control valve

Nozzle cooling oi! tank

Filter

Return main pipe

Supply main pipe

Nozzle

Nozzle Cooling Oil System Diagram

1 DL-20 1A1 87-6

Pressure regulating valve (setting fixed)

IDAIHATSUI

M E M O TYPE 1 SECTION 1

DL-20 . SHEET -

1 DL20 1 Z 1 84 3 1

IDAIHATSUI SECTION TYPE OPERATION AND DAILY MAINTENANCE 5 SHEET DL-20 Preparation for lnitial Starting and Starting after Extended

1 Disuse

1. Preparation for lnitial Starting and Starting after Extended Disuse

( 1) 1 nspection prior to operation Check for:

1) Crankcase interior condition 2) Sufficient feed rate of cooling water; check

for leakage after supplying water. 3) Quantity of lubricating oil and leakage after

feeding oil in: 1. Lubricating oil tank (along with reduction

gears in the case of marine propulsion engine).

2. Rocker arm lubricating oil tank. 3. Turbocharger. 4. Governor, (When model RHD6 or UG8 is

used.) 5. Quantity of lubricating oil to cooling water

pump. 4) Quantity of cooling oil supply to nozzle and

leakage after oil supply. (When heavy fuel oil is used.)

5) Fuel oil quantity and leakage after fuel oil supply.

6) Starting air tank pressure Starting air pressure should always be main-tained at 25 - 30kg/cm2

7) Indicator valve looseness 8) Rack movement

Check if rack and common rod move smoothly. Also check if the graduation on the rack comes to the position of "O" when the control lever is brought to the STOP position. Also lubricate by hand around link.

9) Rotating condition (especially of turning bar) 10) Valve opening/closing of pipelines 11) Neutral position of clutch (in the case of ma-

rine propulsion engine) 12) Drain discharge from intake pipe and intercool-

er outlet. 13) With indicator valve fully opened, tum engine

and check that cylinder is free from fuel oil, water or lubricating oil.

1 DL-20 1 C 1 89-51

o

Corract lavel of oil in the rockar arm lubricating oil tank

Oil port

Turbin sida Blowar sida

Corract laval of oil in tha turbochargar

RHD6

UG8 Correct levei of oil in the governor

IDAIHATSUI OPERATION ANO DAILY MAINTENANCE TYPE SECTION 5 Preparation for lnitial Starting Extended Disuse, Starting

Note: Supply oi! until overflow

Correct levei of oil in the cooling water pump

. (21 Opening and cleaning filters Each of the filters used in the fuel oi!, lubrica-

ting oi!, rocker arm Iubricating oi!, cooling water and nozzle cooling oi! Iines should be opened and cleaned without fail prior to operation to remove dust or other foreign matter gathered there during transport or in mounting.

(3) Preparation for operation 1) Fuel oi! priming and air bleeding

1. Open fuel oi! Iine valves. (ln oi! feed pump at-tached to engine, open check valve at bottom.)

2. Open fuel oi! filter air vent cock to purge air. 3. Open injection pump air vent plug to purge

air.

2) Lubricating oi! priming Prior to operation, after turning and priming

the engine sufficiently, check main bearing, piston pin, crankpin, cam bearing and cylinder Iiner for oi! drip. If operation is to be Iong suspended, spread lubricating oi! over Iiner and piston.

Since piston cooling oi! is injected at 1 kg/cm2 max., check pressure regulating valve for sticking and injection carefully.

Also hand Iubricate rocker arm parts, governor and around common rod link.

and Starting after DL-20 SHEET 2

3) Starting air Keep starting air pressure at 25- 30 kg/cm2 Prior to operation, discharge drain from air

tank. It is desirable to keep air tank handle at 1/3

tum in consideration of high startability and Iow air consumption. 4) Operation of bypass valve

Check for proper flow of cooling water. ln sea water cooling, operate bypass valve carefully. ln the cold seasons, keep Iubricating oi! cooler bypass valve open. Close valve when Iubrication oi! temperature is increased to 35C or more.

If L.O. thermostatic valve is provided, check for its proper operation.

5) Running motor-Oriven pumps for individual lines Run motor-driven pumps for individual tines

and check if Iine pressures and temperatures attain th.e specified values.

For standard pressure~ and temperat.ures, refer to the Operating Specifications shown on Section 3, Sheet 2.

When no warming-up has been done prior to starting, warm up in accordance with the in-structions given in Section 5, Sheet 3 and in-crease the Ioad grad ually.

2. Starting It is advisable to conduct check and preparation

for daily operation in accordance with the instruc-tions given in "Preparation for lnitial Starting and Starting after Extended Disuse: on Section 5 , Sheet 1. But this may be ignored according .to the circumstances, if for example the period of disuse is short.

The engine shou1d be started using diesel fuel oil unless the use of heavy fuel oil is specified.

( 1) Precautionary instructions for starting Before starting, check that: o Operation levei is set at STOP and the rack

amount is reduced to zero. o Rotary section is not obstructed by turning

rod. Cold start (with reference to automatic remote

start-up engine) For initial starting or starting after a Iong in-terruption should start the engine manually

1) Air running Perform the air running 3 times (15 seconds/time)

with the indicator valve held open. Be sure to set the governor control Iever at '1STOP". After air running, the indicator valve should

be closed completely.

DL-20 1 e l a9-5

(DAIHATSUl SECTION TYPE OPERATION ANO DAILY MAINTENANCE 5 SHEET DL-20

3

2) Confirmaon of position of govemor con-trol lever When starting the engine, ascertain that the

control lever is in "ST ART" position. After confirming the following items, move the lever to "RUN" position. The control lever of the auto start-remote control engine is always set in "RUN" position, so it is unnecessary to operate the lever~

Power switch for the protective circuit should be set at "ON" position.

"ST ART" position of governor control lever

"RUN" position of governor control lever

3) Confirmation immediately after starting Pay special attention to the following items

immediately after starting and ensure that there is no abnormality. (ln the case of marine pro-pulsin engine, reduction gear is also included.) I . Oil pressure 2. Cooling water pressure 3. Vibration at various parts 4. Sound 5. Pilot lamp in the protective circuit 6. Others

DL-20 1B1 87-6 1

Starting, Running-in, Warming-up

4) Increase rpm quickly If no abnormality is found among items in

3) above, increase engine revolution quickly to eliminate excessive torsional vibration. Refrain from continuous running at below the designat-ed idling speed.

3. Running-in For running-in operation, use oi! specified in class

1 (Primary oi!), Section 9, Sheet 7. To prevent abi1ormal wear m the initial stage, an

engine specified for operation on heavy fuel oil should be run with diesel fuel oi! for a period of 300 to 500 hours after installation.

Also, sudden increase in load should be avoided as much as possible for a period of 300 to 500 hours af-ter installation, or replacement of piston, piston ring or cylinder liner.

4. Warming-up 1) Warm-up at the rated engine speed (from

idling speed to 500 rpm for marine pro-pulsion engines) for about 1 O minutes under no load. ln the case of an engine having a specific speed region at which torsional vibration must be avoided, such region should be passed as quickly as possible.

2) Warm-up with diesel fuel oil. 3) Prior to warm-up, air-bleed the lubricating oi!

filter, rocker arm lubricating oil filter and noz-zle cooler filter.

Rocker arm lubricating oil filter

Nozzle cooling oil filter

IDAIHATSUf

OPERATION ANO DAILY MAINTENANCE TYPE SECTION 5 Warming-up, Normal Operation

Lubricating oil filter

4) Increase load gradually after engine operation is stabilized. If engine is started when cold, take much time to increase load.

5. Normal Operation (1) Caution during normal operation

1) Measurement of engine performance Measure the following values regularly, under the

sarne operational conditions, as possible, and record the data. These data can be utilized when working out countermeasures in case of change in the en-gine's performance or in the case of an abnormali-ty, and can also serve as reference material for setting up maintenance and inspection schedules.

1. Exhaust temperature at the outlet of each cylinder.

2. Maximum explosion pressure for each cylinder.

3. Intake air pressure. 4. Intake air temperature. 5. Turbocharger rpm. 6. Graduation of the fuel rack indicated for

each cylinder. 7. Temperature and pressure of jacket cooling

water. For details of the standard temperatures and

pressures specified for individual parts and of the operating specifications, refer to the table of operating specifications, Sectioi1 3, Sheet 2 and the operation test results sheets.

Also check exhaust smoke concentration from time to time to ascertain if combustion is going on normally.

DL-20 SHEET 4

2) Intake air temperature It is desirable to keep the temperature of

intake air at 40-50C Adjust the temperature with the cock provided at the inlet side of the air cooler according to the room and cooling water temperature. The manufacturer's "TEST RECORD" is available in connection with the explosion pressure, etc. at full load with the intake air temperature 40 50C. If intake air is overcooled, condensate is formed, with the resul-tant damage to intake valve and reduction in lubricating performance. Therefore be sure to keep intake air at appropriate temperature.

It is generally claimed that the temperature of exhaust gas will change at twice the rate at which intake air temperature changes. How-ever, since the temperature change is affected by the fuel oil fu use, exhaust gas pressure, cleanliness of the turbocharger and intake and exhaust valves, and also by the degree of stain-ing on the ship's hull or the navigation con-ditions (including the shape of the propeller used), etc. in the case of marine propulsion engine, conditions of the installed engine must be understood with reference to the factory operation data. 3) Draining of intake pipe

In turbocharging engines, condensate is likely to collect because of the high intake air pressure and larger intercooler capacty. To cope with this, a drain separator is provided for such engines. The drain separator cock is normally open I/3, and this should be increased as the quantity of condensate increases.

Also open the drain cock installed on the intake air pipe from time to time to drain it. 4) Explosion pressure

The maximum explosion pressure (Pmax) varies according to the nature of fuel oil in use, the intake air temperature, etc. The dis-persion between cylinders should preferably be held within 3kg/cm2 . (However, it should not exceed the design pressure plus 3kg/cm2 .) Measure explosion pressure as described below.

1 DL-20 1 C 1 89-51

fDAIHATSU) SECTION TYPE OPERATION AND DAILY MAINTENANCE 5 SHEET DL-20

5

How to measure maximum explosion pressure

l. Let relieve pressure indicator valve slightly just once.

2. Set pressure indicator. 3. Open pressure indicator valve to the full and

measure pressure. 4. When pressure has been measured, dose

pressure indit:ator valve completely, and tighten lock nut.

S. After reading the maximum explosion pres-sure, open the exhaust valve for the indica-tor and disconnect the indicator after it indicates "O" kg/cm2

(Note) 1. Use gloves, since indcator becomes hot. 2. Measure after suffcient warm-up. 3. When compression pressure is measured by

operating the priming handle, cut off the injection pump and measure at no load. If measured at load, the turbocharger may surge.

In case of a heavy deviation of the Pmax from the design value, adjust by changing the timing of the beginning of delivery of the fuel cam. (Refer to Section7, Sheet 20.)

5) Deaeration of jacket cooling water Throughout engine operation keep open

(fully to 1/2) the deaeration valve at the end of jacket cooling water outlet main pipe so as to deaerate the jacket tine. However, throttle the flow to an extent that deaeration is maintained smooth when jacket cooling water temperature is to be rapidly increased immediately after engine start.

DL-20 1 C 1 89-5

Normal Operation

(2) Daily maintenance 1) Cleaning filters

The various filters should be opened and cleaned periodically to keep them clean at all times. For detail of the cleaning procedure, refer to Section 10, Sheet 1.2. Fuel oil filter

Either metal laminate type filter or notch wire double filter is used, depending on the quality of fuel oil used.

Be careful when heavy fuel oil is used, as the fuel oil and the filter have been heated and become hot.

It is recommended that the filter be over-hauled and cleaned while the engine is out of operation.

@ Full-flow l_ubricating oil filter This is a notch wire type double filter, both

sides of which are normally used. If the lubricating oil pressure falis, the filter should be blown off.

Should the pressure fail to recover the specified pressure levei even after blowoff, open filter and clean.

@ Rocker arm lubricating oil filter This is a metal laminate type filter. Since

rocker arm lubricating oil is contaminated especially heavily, the filter should be turned once a day, witb draining and cleaning upon disasseinbly once a week and once a month, respectively. @ Nozzle cooling oil filter

This filter is the sarne metp.l laminate type as the rocker arm lubricating oil filter.

@ Full flow fresh water filter (for jucket) This is Y-type filtor The cleaning procedures are described in section 10

2) Daily maintenance offiliers 1. Metal laminate typefilter(Self-cleaning type)

Filter Handle Operation

.

IDAIHATSU) OPERATION AND DAILY MAINTENANCE TYPE SECTION 5

2. Notch wire type filter (Blow-off procedures)

Normal Oper ation

During normal operation, the lever should be kept at the upright position, where both filters are in use.

Select lever position with care taken to its stopper and marking position.s, while observing the pressure gauge (at idling or under low load).

Blow-off operation should be performed when the pressure drops during operation. If pressure is not be restored after blow-off, be sure to clean filters.

To perform blow-off, recline the lever to either left or right side blow-off position (to about 60) and then return it to the normal upright position. Repeat this step for one side several times, allowing 1 to 2 seconds for each operation.

Perform blow-off for the other side in the sameway.

The cleaning procedures are described in Maintenance.

Standard blow-off and cleaning procedures are also described on the filter nameplate.

~'Blow-off" Operation Position

3) Lubricating oil pressure regulating valve Standard lubricating oil pressure is 4- 5 kg/cm2

when engine is operated at the rated speed. Pressure is adjusted via the pressure adjust-

ment screw of the lubricating .oil pressure-regulating valve. lf oil pressure does not rise even when the adjustment screw is turned, the valve may stick, or excess intake air or failure in the lubricating oil lines may be considered; investigation of these possible causes is then. necessary.

DL-20 SHEET 6

Adjustment of lubricating oil pressure

4) L.O. thermostatic valve The main function of the L.O. thermostatic

valve is to raise lubricating oil temperature in a short time when the engine 'is started in a cold condition. ln also functions to keep lubricat-ing oil temperature in the proper range (40 -60 C). It is, however, very difficult to keep precise control of temperature and it is not necessary to doso.

lf cooling water temperature changes over a wide range due to seasonal change or change of posi-tion at sea, lubricating oil control temperature may be affected accordingly.

This, however, can be compensated via the adjusting screw. The positioning of cap and lock nut is determined by the nature of the wax used. So, refrain from loosening them un-necessarily.

Even when the thermostatic valve is in order, lubricating oil temperature may sometimes rise excessively, if the lubricating oil cooler be-comes too dirty, volume of cooling water flow decreases, or lubricating oil is heated too much because of abnormal combustfon. Care should be taken as to these phenomena. If lubricating oil control temperature becomes too high due to a defective thermostatic valve, take the following emergency measures: Screw in the adjusting sc;ew (about 8mm max.) and open the valve at the cooler side passage by hand. If the engine (with L.0. thermostatic valve) is equipped with a bypass cock for lubricating oil cooler for emergency use, keep it fully open.

This bypass cock is intended for use when the L.O. thermostatic valve is out of order and is removed. If the engine is operated with the cock closed, it may result in damage to the lubricating oil cooler and the thermostatic valve or in seizure of the engine.

1 DL-20 1 C 1 89-51

IDAIHATSUI SECTION

5 TYPE OPERATION ANO DAILY MAINTENANCE

SHEET DL-20 7

/ L.O. thermostatic valve

ln the absence of such an L.O. thermostatic valve, it is necessary to manually adjust the bypass valve for the lubricating oil cooler to control the temperature of the lubricating oil.

When the lubricating oil temperature is too low during the cold season, a vibrating sound is sometimes heard around the lubricating oil outlet pipe and pressure relief valve due to the high viscosity of the oil. ln this case, open the bypass valve fully to raise the lubricating oil temperature quickly to appropriate temper-ature.

Operation of bypass valve

5) Cooling water outlet thermostatic valve This valve is provided to raise the tem-

perature of cooling y;ater in the jacket line in a short time. when the engine is started from the cold state, and to keep the temperature in the proper range (at around 75C at the engine outlet) during operation.

Careful temperature control is essential, as too low a temperature of cooling water in the jacket line, especially when'heavy fuel oil is in use, is likely to cause insufficient combustion or corrosion of important parts.

For details of the automatic cooling water temperature adjusting valve, refer to the separate manual.

ln the case of an engine without such an automatic cooling water thermostatic valve, perform sufficient warm-up in starting the

1 DL-20 1 C 1 92-9 (

Normal Operation

engine, with the bypass valve in the fresh water cooler fully open, and avoid feeding water of excessively low temperature.

6) Cooling water adjustment flange Throttle the cooling water adjustment flange on

the cylinder head properly so that cooling water will be supplied evenly to each cylinder with appropriate resistance, while reserving sufficient cooling water for the turbocharger and the valve seat cooling line, which are in the bypass line.

Adjust flange so that cylinder outlet tempera-ture difference falis within 3 C of the standard temperature specified in Section 3, sheet 2.

For adjustment flange, refer to Section 4, Sheet 10.

7) Rocker arm lubrication oil l. For details. of the rocker arm lubricating

oil, refer to Section 9, Sheet 3, Rocker Arm Lubricating Oi!.

2. Use manual lubricaton along with the automatic lubrication system to com-pensate for the insufficient lubricating oil immediately after starting.

3. The lubricating oil feed rate will decrease as the oil becomes contaminated. To cope with thiS, the initial feed rate should be set a little higher and lubrication at the valve end position should be checked periodi cally.

Adjustment of lubricating oil feed rate to rocker arm (1)

IDAIHATSUJ

OPERATION AND DAILY MAINTENANCE TYPE SECTION 5 Normal Operation

Adjustment of lubricating oil feed rate to rocker arm (2)

4. Lubricating oi! for the rocker arm tends to become contaminated more heavily than that in other Iines. Therefore, this oil should be replaced more frequently so as not to cause sticking or abnormal wear in the intake/exhaust valves. (It is desira-ble to replace the oil once every 150 to 200 hours of operation).

5. Oil level should be checked at least once a day.

6. Inside of lubricating oil tank should be flushed once a month.

7. Special care should be taken in cleaning inside the lubricating oi! tank with dust cloth or the like to prevent cotton dust or similar foreign matter from blocking the suction inlet port, which may reduce the capacity of the rocker arm pump.

8) Nozzle cooling oil (when heavy fuel oil is used) For detail of nozzle cooling oil, refer to

Se ction 9 , Sheet 4. Optirnum temperature of the nozzle cooling

oil differs according to the kind of fuel oil used and the particular starting method employed (for example, starting with heavy fuel oil). Refer to separate specification to determine proper oil temperature.

9) Turbocharger washing Contamination of turbocharger reduces intake

air pressure, increases exhaust gas temperature or emits black exhaust gas, adversely affecting en-gine performance or service Iife. Therefore be sure to wash turbocharger periodically in accordance with Section 6.

If turbochrger is provided with differential pressure manometer, wash turbocharger when the pressure loss exceeds 200 mmAq. or when intake air pressure is reduced by about IOo/o.

DL-20 SHEET 8

Wash prefilter wound around silencer filter weekly.

For silencer washing procedures, refer to In-struction Manual for Turbocharger.

Turbocharger not contaminated so heavily can be injection-washed during operation. Perform in-jection washing appropriately for the effective use of turbocharger.

Refer to Section !O, Sheet 3 for blower-side in-jection washing procedures and Section !O, Sheet 4 for turbine-side injection washing procedures.

10) Protective devices For each of the protective devices provided,

refer to individual manuais. 1. Should any alarms be actuated during

operation, stop engine immediately and investigate the cause. Close contact should be maintained with the personnel working on the decks so that appropriate actions may be taken in case of an alarm, to prevent accidents in the incipient stage.

2. Each of the protective devices shall be functionally tested at least once a month to ensure that each functions satis-factorily, actuating the alarm whenever an alarm condition is reached. Prior to conducting decreased pressure tests, be sure to throttle the pressure switch takeoff valve to reduce the pres-sure. The pressure reduction in this case takes place only in the pressure switch circuit. Therefore, such testing may be conducted while the engine is run under normal operating condition. The temperature switch can be functionally tested on utiliz-ing the separate hot water line.

11) Adjustment of fuel injection amount If. a cylinder with replaced fuel injection

pump or nozzle differs in exhaust gas tempera-ture from other cylinders, adjust rack scale with adjusting screw shown below.

No adjustment is required if variation in cyl-inders falls within approx. 30C. Variation in racks should be kept at 1 scale.

Do not adjust rack beyond that range. Gradual increase in exhaust gas temperature

may generally result from con tamination in turbocharger or intercooler.

Sudden increase in exhaust gas temperature, on the other hand, may result from damage to propeller or other externai causes.

DL-20 1B1 87-6

IDAIHATSUI SECTION

5 TYPE OPERATION ANO DAILY MAINTENANCE SHEET DL-20

9

< Rack adjustment > Loosen the adjusting screw as shown in

the illustration and adjust the rack to the proper position on the graduated scale. Then tighten screw.

DL-20 1 A 1 86-4

Normal Operation

IDAIHATSUI OPERATION ANO DAILY MAINTENANCE TYPE SECTION 5

Allowable Operational Range DL-20 SHEET 10

6. Allowable operational Range (for marine propulsion engine)

Allowable continuous operation range and recommended continuous normal operational range for marine propulsion engines are shown below.

Values for low load limit may vary according to the output when heavy fuel oi! is in use; the values are normally set at about 35% and 20% for the specifications set up to deal with such low load operations.

( 1) With FPP (fixed-pitch propetler) Allowing for sea margin (hull resistance) created

by soiling of ship bottom, etc., propeller horse-power absorption is designed generally as shown in the graph with respect to the general marine engine characteristics. Such sea margin should be taken into consideration to avoid a torque-rich state in the engine as a result of soiling on the ship's bottom, which may lead to possible damage of the parts constitu ting the com bustion cham ber, or may render proper engine maintenance at proper intervals impracticable. It is therefore, necessary to understand the accurate operational performance of the engine and operate it within the recom-mended range at ali times.

An excessively torque-rich condition may some-times induce a surging effect in the supercharger.

it::] Allowable operation range b:J Recommended continuous normal operational range

1 60

40

20

50 60 70 80 90

ldling speed

(2) With CPP (controllable-pitch propeller) ln a CPP, the vane angle can be changed to

match different engine speeds, allowing optional selection of engine output (load). This feature contributes to fuel saving and permits optimum engine operation through proper combination with other auxiliary equipment driven by the marine propulsion engine.

Because of its greater degree of freedom, how-ever, it tends to produce a torque-rich sfate in operation. To handle this, it is desirable to operate the engine on a planned schedule, with thorough understanding ofthe engine's allowable operational range and with the use of an ALC (automatic load control device) if possible.

Where generator or other auxiliary equipment is driven by the main engine, loads to be applied by the concurrent operation of the propeller and the auxiliary equipment and by independent oper-ation of such equipment should also be taken into full consideration, so that the engine will be operated within the recommended continuous normal operational range.

When deviation from the allowable operational range, as shown below, is inevitable dueto special specifications, the proper operational range should be determined in accordance with user specifica-tions or other instructions mutually agreed upon.

P curve: marine propulsion engine characteristic curve

M curve: curve taking sea margin into consideration

Propeller design point

95 100 105

___ .. ..,. Revolutions

Allowable operational range

DL-20

IDAIHATSU) SECTION TYPE OPERATION AND DAILY MAINTENANCE 5 SHEET DL-20

11

7. Stoppage ( 1) Precautionary instructions

1) lnspect every section of the engine at the time of stoppage to ensure that no trouble will occur at start up.

2) Stop the engine in an unloaded state (with the clutch in neutral in a marine propulsion engine.) ln order to let the engine coo! down gradually,

be sure to operate under no Ioad for about 10 minutes where diesel fuel oi! is used, before stop-ping the engine, except for the case of an emer-gency, or operate under no load for 3 - 5 minutes when blended fuel oi! (or heavy fuel oil) are n use.

3) ln an engine with a turbocharger, ascertain that the turbocharger has stopped smoothly. Generally it will take two to four minutes after the stoppage of the engine till the turbQ-charger comes to a complete stop. The matter should be checked when the ship is tested at launch.

4) After the engine has stopped, open the in-dicator valve and tum the engine over several times so that the combustion gas is discharged.

After the engine has b~ stopped, run lubri-cating oi! priming pump for about 10 minutes and cool piston down gradually.

5) Leave the cooling water undrained until the engine is completely cooled.

6) It is recommended that cooling water be drained from the engine and turbocharger, when the stoppage is expected to be prolong~ ed.

The cooling water should be drained with-out fail in winter as it may freeze and cause damage.

(2) When engine must be stopped immediately 1) When alarm monitor functions. 2) When an abnormal sound is heard from the

working parts of the engine. 3) When smoke is observed at bearings or

other working parts. 4) When lubricating oil pressure drops

suddenly. 5) When lubricating oil temperature rises

suddenly. 6) When engine revolutions increase rapidly

due to trouble in the governor or fuel injec-tion pump.

7) When supply of cooling water has stopped and water can not be supplied immediately. (Refrain from supplying cold water suddenly after overheating.)

f DL-20 1 B 1 87-6 1

Stoppage, SpeCial Operation

8) When temperature of the cooling water has rsen too high and no adjustment is effective in lowering it.

9) When any damage or looseness of screws or bolts of working parts is detected.

1 O) When piping for fuel oil, lubricating oil or cooling water is found to be broken.

11) When moisture is found mixed in the lubricating oil.

12) When turbocharger rpms and discharge air pressure decrease or exhust gas temperature rises to an abnormal levei.

13) When propeller or shaft is out of order. (This applies to marine propulsion engine.)

(3) Precautionary instructions to be observed during stoppage (These commonly apply during outfitting of a ship as well.)

1) When the stoppage .is expected to be prolonged, take rust preventive measures with regard to the engine. Apply rust preventive oil to the exposed machine-finished portions and cover the cylinder head.

2) Operate the engne more than once a week for about 10 minutes so that lubricating oil film is not lost. When this cannot be done, turn engine over several times to change contact positions of pistons, bearings, cams, etc.

3) Apply proper covers to the exhaust silencer, air filter ofturbocharger and mist gas vent pipe to prevent water from entering.

4) Apply cover over all the electric equip-ment, so that insulation resistance will not be impaired.

8. Special Operation ( 1 l Low Ioad operation

1) Operating the engine at low load for a long stretch of time should be avoided insofar as possible, as this may result in contamination of ir intake system and the combustion chamber due to the counter flow of the exhaust gas, incomplete combustion or abnormal wear ofindividual parts.

2) Low load limit varies according to the engine specifications. If engine must be run below the low load limit, use grade A heavy fuel oil without fail and restrict operation to as short period as possible.

(DAIHATSUI OPERATION AND DAILY MAINTENANCE TYPE SECTION 5

Special Operation

3) To maintain a satisfactory combustion state, adjust intake air cooler outlet cock. Increase in-take air temperature with care taken to keep cylinder outlet exhaust gas temperature below 450C.

If the water is reduced until intake air temper-ature exceeds 75C, scales are formed in fin tube. Therefore be sure to keep intake air temperature below 75C.

3/4 or more load operation for 30 minutes af-ter low load operation is effective to prevent con-tamination of combustion chamber and intake/exhaust system.

4) It is desirable to minimize low-load operation insofar as possible. If it takes a long time, be sure to increase injection washing of turbine or blower.

(2) Non-turbocharger operation Each vessel is provided with a set of turbo-

charger blank plates ( or exhaust relay pipes) so that the engine can be operated when the turbo-charger is out of arder. Load in this case is gener-ally at Pme (average effective pressure), which equals 4.5 kg/cm2 (about 25 "" 30% of the rated output). Since the carn and pistons are conditioned for turbocharged operation, exhaust gas temper-ature becornes quite hgh. Thus, when contnuous operation is req ured under non- turbocharger con-dition, take greater care with exhaust gas ternper-ature than load; operate the engine with the ex-haust gas temperature kept below 450C using diesel fuel oil.

ln non-turbocharged operation, refer to Section 1 O, Sheet 5 for the use of turbocharger blind plate and exhaust gas relay pipe.

(3) Operation with intercooler cut off from main line

If fin tube for the intercooler is broken or if water leaks into the air supply system, cooling water (sea water) may flow into the cylinders through the intake air line.

This may result in corrosion in the air supply system or in the parts constituting the combustion chamber, or damage to these parts. To avoid this, take the following countermeasures promptly if a failure in the intercooler is detected.

1) Stop feeding water to the intercooler and drain cooling water remaining inside the inter-cooler.

2) As a make-shift measure, operate the engine with diesel fuel oi! with the intake air temperature kept at 70C or lower and exhaust gas temperature at less than 450C.

DL-20 SHEET 12

When resuming supply of cooling water after temporary suspension, check carefully for any leakage of water through packing.

3) When the intercooler can be overhauled, check for the following and repair. 1. Fin tube damage 2. Fin tube expansion failure 3. Packing defect at air intake side drain hole

If the fin tube has broken, plug the cooling water inlet and outlet associated with the damaged tube with the wooden plugs supplied and continue operation.

Since the cooling efficiency of the inter-cooler is diminished in this case as well, con-tinue operation, paying attention to the tem-perature of exhaust gas.

(4) Operation with reduced number of cylinders Operation of diesel engine with reduced

number of cylinders should be restricted to emergency use for only a short period, because of the possible torsional vibration or externai vibra-tion which may accompany such an operation. Care should be taken of the following points when performing such an operation.

1) Expected output should be limited to: (Number of Number of cylinders - cylinders inoperative) x 70%

Number of cylinders If outlet temperature of each cylinder exceeds

the tolerance, reduce load furthermore. 2) Because of the increased vibration torque

exerted on flexible joints and reduction gear in the case of a marine propulsion engine, care should be taken to prevent damage thereto, and also for chattering. Refrain from operat-ing at the rpms at which chattering takes place.

3) ln the case of an engine used for a gene-rator, the vibrational stress exerted on the generator shaft may exceed the allowable limit established by the Ships Classification Societies. ln such a case, pay attention to the sound of the gears located at the front end of the engine and refrain from operation if the levei of sound is greater than normal.

4) When the engine is operated with some pistons and connecting rods removed, externai vibration of the engine may increase. ln such a case, refrain from using it if the vibration is excessive. This is particularly true with a flexible mount-ing system, so special care is necessary for type of engine:

l DL-20 1 C 1 89-5 1

IDAIHATSUI SECTION

5 TYPE OPERATION ANO DAILY MAINTENANCE SHEET DL-20

13

lt is preferable to inquire of the manufacturer and observe the instructions gven. For proper treatment of the lubricating oi! feed holes etc. left open as a result of the remova! of some pistons and connecting rods, please contact our Service Division.

5) If surging takes place, open drain cock to purge air.

ln this case, take due care of increase in ex-haust gas temperature.

(5) Measurement of compression pressure Turn the fuel oi! prirning Jig by 180 to shut off fuel oil supply. Measure pressure inside the cylinder in this state. (Be sure to tum the priming jib as quickly as possible by 180; the notched part on the prirning jig may be damaged if it is turned slowly by resting on half-way.)

Fuel oil priming jig

Fuel oil pump push rod

' Fuel oil cam .

T 1

Measurement of pressure inside cylinder is taken with fuel supply to the cylinder being cut off, which applies a torsional stress to the crankshaft. Therefore, it must be finished in as.shortest time as possible.

Special Operation

IDAIHATSU)

M E M O TYPE 1 SECTIDN 1 DL-20 . SHEET -

1 DL-20 1 Z 1 84 3 1

(DAIHATSUI SECTION

6 TYPE MAINTENANCE SCHEDULE

SHEET DL-20 1

1. Maintenance Schedule (1 ) General precaution

Periodic inspection and maintenance are essen-tial to keep performance from the engine.

Standard overhauling intervals differ greatly according to application, working conditions and quality and control of fuel and lubricating oils. It is recommended that a schedule be worked out to match the individual engine, using the table shown on the next page as a guide.

DL-20 1 Z 1 84-3

General Precaution

The standard overhauling intervals shown here are intended for engines that have undergone breaking-in and have entered normal operation. The first overhaul on newly built ships should be performed earlier than normal and engine condi-tions should be fully understood.

MAINTENANCE SCHEDULE Maintenance lntervals (Diesel fuel oil)

lnspection Item Task Monthly 3 mon. Daily Weekly 300- 1,000-

500 1,500

Cylinder head cover Check of interior (check for smooth rotation o the rotator etc.)

Fuelnozzle Check injection pressure * and condition, clean

lntake valve Inspect and fit

Exhaust valve ln spect and fit

~ ~ Inspectand fit "" .. lnspect and fit .. .e 11 Rotatot lnspect overhaul i! = ,., u Valve spring lnspect

Valve end clearance lnspect and adjust o Valve opening/closing lnspect time

lnspect overhaul Cylinder head Check cylinder head

fixing torque Extract piston, clean, measure and inspect

Pston Inspeet piston.!~g lnspect and measure

pin t piston pin bearing

Connecting rod lnspect crankpin bearing Check tightening Iorque of connecting rod bolt lnspect and measure interior

Cylinder liner Extract liner and inspect jacket lnspect and measure crankpin and journal Measure deflection and

~ Crankshaft adjust "'

Ch eck tigh tening torque .. or balance weight fixing . 5

~ bolt e Inspect main bearing Main bearing metal ::. Cheek tightening torque

of main bearing bolt Check cam and roller o fitting Check tappet and bush fitting

Camshaft lnspect and measure carnshaft

lnspect camshaft bearing

Check fuel cam fixing nut * tightening Iorque

Check tooth meshing and backlash

Timinggear lnspect idle gear bush

Check tightening boi! torque ..

Check amount of operation o oil e

. Check and replace operation I:~ Governor;

* 8!Z. oil -.;"! Disassemble and inspect &: fl major parts

Fuel control link lrispect o Adjust and lubrica te o Disassemble and lnspect

Pumps Replace seal

]~ Clibrate tachorneter .. lnspeet pressure gauges ..

~i Gauges and thermometers lnspect vibrationabsorb spting for gauge board

Safety devices lnspect, test and adjsu t o

(DAIHATSUJ TYPE SECTION 6

DL-20 SHEET 2

Running Hours 6 mon. 1 yr. 2,000- 4,000-

3,000 6,000

C2 : o Olc)

* o 0 z; e, o .. ,O--'-~ o e ;r';., t

"

o C'- ,~ Color penetran t check once every 4,000-6,000 Jus. of operation Afier l-0 hn. in smke for lhe initi11 chcck

o "'( '.)Ll j /

o 0-i,t(l,

* o

IDAIHATSU) SECTION TYPE MAINTENANCE SCHEDULE 6 SHEET DL-20 Maintenance lntervals (Diesel fuel oil)

3

Running Hours Inspection Item Task Monthly 3 mon. 6mon. 1 yr.

Daily Weekly 300- 1,000- 2,000- 4,000-soo 1,500 3,000 6,000

Check amount of Jubricating o oil /

s Replace lu bricating oil 11 Every 500-1,000 hrs. ~ ~ Clean air cleaner / o

.:= Disassemble, clean and .' "'

Turbocharger '

o ~ inspect jacket .,

,/ Refer to Turbocha.rger ... Replace lubricating oi! / - o v~

(.) Lubricating oil / ,' .5 Inspect _and replace / o N coo ler e.~ Inter cooler Inspect and replace ./ o ,,,,,_ Check for leakage o ~ Piping Check for loose bolts/ o 1l nuts Check for leakage o

Exterior of engine Check for !oose bolts/ o nuts Full flow fresh water Disassemble and clean I o filter

DL-20 ls~I

(DAIHATSU) MAINTENANCE SCHEDULE TYPE

SECTION 6

Maintenance lntervals (Heavy fuel oil) DL-20 SHEET 4

Running Hours

lnspection Item Task Monthly 3mon. 6mon. l~ Daily Weekly 300- 1,000- 2,000- 4 soo !,SOO 3,000

Check of in tcrior Cylinder head cover (check for smooth rotation

lhe rotator etc.) o

Fuelnozzle Ch eck injection pressure * 700-1,200 hrs. and condition, clean Exhaust valve lnspeC and fit * 3,000-4,000 hrs.

~ lntake valve lnspect and fit o "'

S tarting air valve lnspect and fit o l Cylinder safety lnspect and fit o .. "'

valve ~ Rotator lnspect overhaul 1 o ~ o Color penetrant clteck u V alve sprng lnspect once every 4,000-6,000 hrs.

of operation Valve end clearance lnspect and adjust o Alirr Sll ho. n smitt for tire inrtal check Valve opening/closing lnspect o time

lnspect overhaul o Cylinder head Check cylinder head

* o f'JXng Iorque Extract piston, cleant measure and inspect o

Piston lnspect piston ring o lnspect and measure o piston pin Inspect piston pin bearing o

Connecting rod lnspect crankpin bearing o Check tightening Iorque

* o ~boi! re o

Cylinder liner Extract liner and inspecl Every 4 yrs. jacket (16,000-24,000 h.rs.} Jnspect and measure llvery 2 yu. crankpin and journal (8,000-12,000 hrs.) Measure deflection and o Crankshafl adjust

~ Check tightenng torque o or balance weight fiicing a. bolt .5' lnspect maJn bearing Every 2 yrs. > o metal i (8,000-12,000 ltrs.) s Main bearlng .s Check tighten1g Iorque o 1 .. of main bearing bolt ::;

Check cam and roller o fitting 1 Check tappet and bush Every 2 yrs. fitting (8,000- 12,000 hrs.)

Camshaft lnspect and measure Every 4 yrs. camshaft (16,000-24,000 hrs.) lnspect camshaft bearing Every 4 yrs. (16,000-24,000 hrs.) Check fuel cam fi.xing nut

* \Vhenever fuel injection

tightening torque tning is adjusted Check tooth meshng and Every.2 yrs. back:lash (8,000-12,000 hrs.)

Timinggear lnspect idle gear bush Every 2 yrs. (8,000-12,000 hrs.) Check tighterung bolt Every 2 yrs. Iorque ( 8,000-12,000 hrs.) Check mount of operation o RHD6 or UG8 Governor oi;

. ~ Governor Check and replace operation * o RHD6 or UG8 Governor "ti oil 8 " Dsassemble and inspect li major paris o "-~

Fuel control link lnspect o Adjust and lubricate o

Pumps Disassemble and inspect o Replace seal o Whenever lcakllge is found ~~ Calibrate tachometcr o 5 :!f ~~~~~!f.:;~':,~fe::uges ;a .. o

"" Gauges ~1 Inspect vibraton~absorb =t o spring for gauge board Safety devices lnspect, test and adjsu t o

Note: ltems marked *denote those to be checked at time of first inspection. The first inspcction for these items sltoud be as early as practical; optimum interval for disassembly for inspection should be determined accordng to the actual findings on lhe first inspection.

[DAIHATSU) SECTION TYPE 6 MAINTENANCE SCHEDULE SHEET DL-20 Maintenance lntervals (Heavy fuel oil) 5

Running Hours Inspection Item Task Monthly 3mon. 6mon. 1 yr.

Daily Week!y 300- 1,000- 2,000- 4,000-500 1,500 3,000 6,000

Check amount of lubricating o oil

e Replace lubricating oil Every SOO- 1,000 hrs. li> ;,;;

Clean air cleaner o ~ .~

Turbocharger Disassemble, clean and o "' inspect jacket -:;; " Refer to Turbocharger .. Replace bearing ~ Operation Manual .,

Every 150,;,200 hrs. "

F1ush blower side .>( :l Flush turbine sde Every 150-200 hrs. .5

Intercooler Disassemble and clean, o hydrostatic leak test

-~ S tarting air valve Inspect o ';; and starting con- Drain condensate o E trol valve " lnspect rotary valve, o ge S tarting rotary ~~ check seat fitting .... valve

D rain condensate o ::: >-.. ~ ~

S tarting air Check air pressure o ri tanke Drain condensate o

Check rack graduation o position E Fuel injection Check fuel injection o ., pump timing -:;;

~ Disassemble, clean and o :;:: inspect o ;; Drain condensate o ~ Blow-off (for notch wir o If fuel oil pressure falis Fuel oil filter type filter)

Disassemble and clean *

Depends on fuel oil conditior Check lubrica ting oi! o

Lubricating oil quantity E tank Make-up or replacement ~ Analyze oil properties o depending on result of ~ analysis ' Drain condensate o "" Full-flow filter Blowoff (for nmch wire type fiher) o If Iubricating oi! pressure "' falis .: z Disassemble and clean o " ...l Lubricating oil Every 2 yrs.

coo ler Disassemble and clean (8,000-12,000 hrs.) .!. Check quantity of o "' Rocker arm lbri- Jubricating oil " ~ cating oil tank Replace rocker arm lubricating Every 150-200 hrs. oil, disassemble and clean :::

o ;::: :::: Drain condensate ~~ ~- Rocker arm lubri- Clean while turning with li> ., o .>( >-()"' cating oil fil ter handle o OI)

e

IDAIHATSUI

MAINTENANCE SCHEDULE TYPE SECTION 6 Manual Lubrication Maintenance lntervals DL-20 SHEET

6

(When disel fuel oil and heavy fule oil are used) Equipment Lubrication Lubrication Interval Lubricant Used Remarks

Cooling water pump *Oil cup Weekly # 30 engine oil Replace with new oil every 6 months. (by removing plug)

Governor Handle Every 3 months Grease

Fuel oi! control

fDAIHATSU) SECTION TYPE MAINTENANCE 7 SHEET DL-20 General Precautions for Disassembly, Assembly and

1 Adjustment

7 - 1 General Precautions for Disassembly, Assembly and Adjustment

General Precautions for Disassembly, Assembly and Adjustment Prior to disassembly, assem bly anl /or adjustment of the engine, the engine in-ternai construction and standard adjustment pro-cedures should be fully understood, and the standard maintenance procedures to be described herein read thoroughly. 1. Handle the engine and other parts carefully

"Safety first" should always be your slogan. 2. Give heed to the assembly sequence and

tally marks to avoid misassembly. 3. When disassembling jointed parts, pay special

attention to the match marks. If the match marks are not provided or are blurred, mark them clearly. When overhauling parts associat-ed with specific cylinder numbers mark them with paint or magic pen so that they can be clearly identfied in assembly.

4. Each disassembled part should be put in a designated box or the like container in good order or kept neatly in designated places to avoid misplacement.

5. Do not mix the special heat-resistant bolts and nuts used with the exhaust pipe, etc. (exposed to. high temperature) with other kinds of bolts and nuts in assembly.

6. Tighten bolts and nuts with even force observ-ing the correct tightening torques, as specified on Section 3, Sheet 4.

7. Check periodically for looseness of bolts and nuts for internai components which are not overhauled.

8. If tuming is necessary midway in disassembly or assembly, ensure that there are no parts that may come into contact . with the rotary part and that there is no danger to the per-sonnel working nearby.

9. Use standard tools when disassembling and assembling the engine.

10. When disassembling, take specified measure-ments at as many points as possible; data thus gained should be filed for later reference.

11. Packings should be replaced at each dis-assembly. So a sufficient number of packings should be at hand to match the degree of dis- . assembly.

12. When some spare parts are used, replenish them at once.

13. From the viewp_oint .of full utilization of engine performance, with appropriate periodic overhauling intervals, and of the interchange-ability and accuracy of the parts used, Daihatsu genuine parts should always be used.

14. Cover each of disassernbled parts without fail to keep out dust.

15. Before assernbling, mke sure that ali parts are clean. If any are soiled, wash with gas oil, or air-blow clean.

If you have any questions concerning about handling and main-tenance, please contact a Daihatsu Service engineer.

DL-20 1B1 87-61

MAINTENANCE Cylinder head, High pressure fuel

7 - 2 Disassembly, Assembly and Adjust-ment of Main Parts

1. Cylinder Head and Related Parts / (1) Cylinder head

< Overhauling process > 1. Remove cylinder head top cover. 2. Disconnect all pipings around cylinder head. 3. Remove rocker arm shaft holder. 4. Disconnect hgh pressure fuel pipe. 5. Remove cylinder head lower cover. 6. Remove push rod and protective sheath. 7. Remove cooling water regulating cock. 8. Remove nozzle holder. 9. Unscrew exhaust pipe fixing bolts.

10. Unscrew intake air pipe fixing bolts. 11. Remove indicator valve. 12. Remove cylinder head tightening nuts. 13. Remove cylinder head.

< Precautions > 1. When detachng cylinder head, take care not

to damage. fit-up surface of 0-ring fitted to cooling water guide.

2. Before scraping carbon deposits from com-bustion chamber, check deposit condition and quality.

3. Remove carbon deposits from combustion chamber and carefully check for cracks.

4. Since cylinder head packing has the impor-tant function of sealing high pressure gas, always replace it, insofar as possible, at each overhaul.

Since cylinder head packing seat section is susceptible to flaws, give special care to handling.

5. .Check for corrosion on fit-up surface of 0-ring for cooling water guide, and also for gas leakage through cylinder head packing. Minor corrosion or gas leakage should be corrected at once.

6. Check and remove fur accumulated on water jacket of cylinder head at least once every two years. If not cleaned for a long time, cooling efficiency drops, water passage is clogged and cracks may develop.

7. Upper surface of cylinder head serves as teturn passage for rocker arm lubricating oil. Clean this surface with care so that foreign matter such as dust or cotton waste, etc. does not enter lubricating oil.

8. When lifting cylinder head, lift it horizon-tally. Take care not to allow water inside jacket to enter cylinder.

9. Loosen cylinder head fixng nuts gradually n the sequence shown below, so that ali are loosened completely after second run. Loosen-ng each one fully at once will exert undue strain

oil

(DAIHATSUI TYPE SECTION 7

pipe DL-20 SHEET 2

on other bolts still tightened firmly. Proceed n the sarne manner also when tightening to fix cylinder head.

Loosening cylinder head fixing nuts (Numbered for sequence of loosening.)

10. When loosening cylinder head tightening nuts, use a box spanner. Use torque wrench only for tightening.

11. Thke special care in setting cylinder head so as not to scratch or dent packing surface of cylinder head or Iiner or fixing nut. Clean thoroughly to remove dust, etc. before fixing.

"ln consideration of nitial run-in, it is desirous to retighten cylinder head tightening nuts at an early stage after launching:

12. Tighten intake/exhaust pipe fixing bolts prior to tightening cylinder head fixing nuts.

Cylinder head adjust intake/exhaust pipe flange face to face.

(2) High pressure fuel oil pipe When conneting high pressure fuel oil pipe to

nozzle holder or disconnecting it, use double span-ners so no torque will be exerted on inlet connector.

High pressure fuel oil pipe should be handled with good care as it is subject to very high pres-sure. Special care should be taken not to scratch the fit-up surface of each fitting and joint. (Disassembly procedure) ..... (For extracting nozzle holder on A type or H type)

1. Remove 0-ring guide set bolt. 2. Displace 0-ring guide toward holder side. 3. Using special spanner provided, remove cap

nut at holder side. 4. Displace tube retainer upward. 5. Loosen cap nut at pump side. 6. Rotate nozzle holder sideways and detach

fitting to high pressure pipe from nozzle holder.

7. Extract nozzle holder. For B type, carry out steps 3. through 7. described above.

oL-20 1e1 as-s I

IDAIHATSUI SECTION TYPE

7 SHEET DL-20 High

3

< To extract B type high pressure fuel oil pipe > Remove cap nut at pump side in step S. above and pull out the pipe along wth the cover.

Nozzle holder

1 tT_J . 1

1 i

3

Cylinde~ head cover)I

2 1 ! 11 ((

) '

;:L Fuel injection pump_..-r: ,''=F!,. : l;=:f:_:\

. i Disassembly of high pressure fuel oil pipe {A type)

Fuel injection pump

MAINTENANCE pressure fuel oil pipe, Fuel nozzle

holder 3

Fuel injection pump __--.,..------~-..,........

Disassembly of high pressure fuel oil pipe (B type)

(31 Fuel nozzle Since maintenance of the fuel nozzle has a great

effect on the condtion of combustion and output, be sure to disassemble and inspect it whenever any change in exhast gas temperature or color is noted.

Be sure to use the nozzle specified on the factory operation data sheets.

Before removing nozzle, check condtion and quality of carbon deposits.

< Nozzle injection testing > 1. Detach the high pressure fuel oil injection

pipe and other piping, and remove nozzle from cylinder head using nozzle holder dis-assembly tool.

Disassemble of high pressure fuel oil pipe (H type)

Nozzle extraction

DL-20 1 C 1 89-5

MAINTENANCE Fuel nozzle

2. Before removing nozzle, measure and record nozzle injection pressure.

3. Remove pressure adjustment bolt cover of nozzle holder; loosen pressure adjustment bolt.

4. After removing carbon deposits, detach noz-zle from holder.

Be sure to loosen the pressure adjust-ment bolt without fail when attaching nozzle to nozzle holder, or detach-ing it from the noz-zle holder. (for avoid mal-atomi-zation) Nozzle extraction

5. Clean carbon from nozzle tip.

Nozzle cleaning

6. Attach nozzle to nozzle tester; set injection pressure as specified on Assembly and Ad-justment Table shown on Section 3, Sheet 1.

Nozzle testing

(a)

IDAIHATSUI TYPE SECTION 7

DL-20 SHEET 4

Pressure adjustment bolt

' .

/

' , . ' ._,

Adjusting fuel injection pressure

< Precautions > 1. Operate the nozzle tester hand lever at a stroke

of 4- 6 times per second and check the spray mist to see that it is uniform without abnormal-ity due to the blocked injection hole.

Sliown below are different conditions of fuel spraying through injection nozzle.

~ )t( ~ 1 ' 1 . "'

Clogging in (b} Malfunction (e) Dripping nozzle of needle valve of fuel oil

Fueloil ~

(d) Normal state of injection

DL-20 1 C 1 89-51

IDAIHATSUI SECTION TYPE

7 SHEET DL-20 Fuel nozzle,

5

2. When removing nozz1e, be sure to loosen nozzle holder pressure adjustment bolt. When remounting, pressure adjustment bolt should be loose. Nozzle removal/remounting with pressure adjustment bolt tightened may damage needle and cause mal-injection.

3. ln nozzle testing, check carefuDy also for wear or corrosion of needle valve, and replace it if worn.

Special care should be taken as to injection port wear, which is likely to occur when heavy fuel oil is used.

4. Check for smooth movement of nozzle and needle; replace if either is stuck.

Do not fit nozzle and needle with lapping agent.

Nozzle and needle are used as a pair; do not intermix pairs.

5. After cleaning nozzle and needle of carbon, wash in clean gas oil and air-dry.

6. Before fitting tested nozzle to nozzle holder, clean mating. faces thoroughly to remove dust or other foreign matter; then tighten with correct torque as specified in the Tightening Torque Table shown in Section 3, Sheet 4.

Tightening with excessive torque may result in sticking of needle valve.

7. Since the high pressure fuel injection pipe is subject