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FUEL SYSTEM 3-152) Install the key on the camshaft, then installthe automatic timer by aligning its keygroove with the key on the shaft. Install thespring washer and round nut.

.3) Instal.1 the ~eed pump.~ 4) Install seal lead and wire on the smokesetscrew and maximum speed adjusting bolt.-5) When installation is completed. fili the jnjec-tion pump with the specified oil from thepump side.

2-5 .Adjustment of injection pumpFIG.3-42(16) Install the pneumatic governor in thefollowing manner:Install the diaphragm. then install the pneumaticgovernor together with the pneumatic governorspring and adjust shims.NOTE: Apply a thin coat of diaphragm oil(55413-132) to the leather before install-ing the diaphragm assembly. When thediaphragm assembly is installed on thegovernor housing, apply grease to thecaulked portjon and governor housingfitting face of the diaphragm to preventair leaks. Keep diaphragm leather free

from grease.PAY CLOSE ATTENTION

(1) Preparation for adjustmentInstall the fitting plate (5781-005) on the injec-tion pump.1) Install the testing coupling assembly(5784-004) on the injection pump camshaft.2) Mount the injection pump assembly on theinjection pump tester.3) Bleed the injection pump completely.

The injectjon pump should be tested and adjustedusing an injectjon pump tester after overhauljng.Testing and adjustment procedures are descrjbedin the later paragraphs.(17) Instaltation of jnjectjon pump after

adjustment1) When injection pump adjustment is com-pleted, install the pump bracket on theflanged face of the injection pump housingby .aligning the notched lines.,

,.. FIG. 3-44(2) Control rack zero position setting1) Connect the control rack measuring device(5782-601) to the injection pump control

rack.2) With a screwdriver. depress the control pin-ion clamp screw in direction of fuel stop untilthe control rack comes to a stop. then cali-brate the scale (and vernier scale) to zeroand fix the measuring device in that position.Keep the idling spring unhooked durjng themeasurement.FIG. 3-43

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3-16 FUEL SYSTEM(3) In5pection of control rack 5troke1) Tilt the stop lever aJI the way in direction offuel increase and check that the stroke of thecontrol rack is in excess of 15 mm.If the measured v.alue is less than thespecified range. recheck setting of the rela-tive parts and if necessary, adjust by install-

ing a shorter push-rod.PUSH-RODSAVAlLABlE

camshaft slowly in counterclockwise direc-tion as viewed from the drive sjde of the in-jection pump and check that fuel stops flow-ing out from the nozzle holder overflow portwhen the tappet js lifted 2.25 .: : 0.05 mm(C240)..If the timjng is too fast or too slow. adjustwith the tappet adjusting washers. To adjustthe injection timing. proceed as fo1lows:; Turn the cam to a pojnt correspondjng.to the

.top dead center and insert the spring"hoJder(57931-410j into the groove in the tappetbody and turn the camshaft to bring the camto a pointcrresponding to the bottom deadcenter, then adjust the totaJ thjckness of theadjusting washers fit ted between the tappetand fower sprjng seat.

\

."'

2) Tilt the stop lever alI the way in direction offuel stop and check that the stroke of thecontrol rack is less than 1 mm. If the mea-sured stroke is in excess of 1 mm, rechecksetting of the relative parts.(4) Injection timing adjustment1) Bri ng the tappet i n the No.1 barrel to thelowest position corresponding to bottomdead center by turning the camshaft slowly.2) Hold the finger of plunger stroke measuringdevice (5782-402) over the tappet guide anddepress the measuring device in toward theplunger while pushing it to one side of thetappet chamber cover opening.

c.c...~- -~~~~_. .FIG. 3-465) Check the fuel Stop point of each barrel insequence of 1-3-4-2 by turning the camshaftcountercloCkwise slowly with hand andmake necessary adjustment with the tappetadjusting washers. So that the injection tim-ing of each barreJ is 90 : : 30. apart a~checked with the graduationS on the pumptester flywheel.

FIG.3-476) The tappet adjusting washers are available in17 different thicknesses as follows:

FIG. 3-453) Turn the camshaft sfightfy jn both djrectionswhife reading the djal indicator. When thediaf indicator needle stays stifl (it indjcatesthat the tappet js resting at the lowest posi-tion) cafibrate the dial to zero.4) Check that the control rack~~on the fullloadside (stroke is 10 mm or more). then turn the

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FUEL SYSTEM 3-17

3) Injection volume can be adjusted by turning, the control sfeeve after loosening the controlpinion clamp screw.Injection volume increases when the controlsleeve is turned counterclockwise and de-creaseswith clockwise turning of the controlsleeve.

7) Check the= tappet clearance of each .barrelwith the tappet re~ting .at the top: deadcenter. If the clearance is less than 0.3 mm,recheck injectio, ti_ming and setting (of theparts. "- -(5) Adjustment of injection volume (First Step)1) The injection volume should be tested andadjusted under the following condition.

Iniectjon nol e.njection nozzleholder ..

Injection starting pressureIniection l neesel fuel usedransfer pump pressure .

5780.0005780-208175 kg/cm2Outside dia. 6 mm X Inside dia. 2 mm -Length 600 mm

80SCHOILorASTM2D1.6 kg/cm2

NOTE: The nozzles, nozzle ho(ders and injectionlines described above are attachments prepared f.or the injection pump tester anddjffer from those of the actual engine equippedon the vehicle. When the adjustment shouldbe made using nozzJes. holders and/or linesof the actual engine equipped on the vehicle.p(ease contact with the Export Service Dept.of Isuzu Motors Ltd.

2) With the control rack guide screw(57976-310), fix the control rack in thespecified position and check the injectionvolume by operating the pump at thespecified speed. (See tables 3-1 & 3-2).IN CASE OF ADJUsTMENTUsiNG BOsCH OIL OL61V 11:

FIG. 3-48Far C240:

-CONTROLRACKPOSITION (mm) PUMPSPEED(r.p.m.) INJECTION VOLUME(c.c/1000st.) REMARKSEVIA TION(%).:t. 2.5.:t.14.0

Basis1.98.4

1900300 42.7 44.77.9 10.1TABLE 3-1IN CASE OF ADJUSTMENT USING ASTM NO. 2D DIESEL FUEL:

Far C240:CONTROLRACKPOSITION (mm) PUMP SPEED(r.p.m.) INJECTION VOLUME( c.c/1 OOOst.) REMARKS8asis

DEVIATION(%)

~ 2.5+14.011.98.4 1900300 41.0- 43.06.9 -9.1TABLE 3-2

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3-18 FUEL SYSTEM

NOTE: 1 smoke set screw. so that the control rackstroke becomes 12.7 + 0.05 mm {C240).

2-6 Adjustment of RBD type gover;nor

(1) Testing cf pneumatic gcverncrMake a leak test on the governor chamber in thefollowing manner: Drive the injection pump at500 r.p.m. and apply negative pressure of 500mm Aq to the governor chamber and check thetime taken for negative pressure to drop to 480mm Aq. Normal condition of the governorchamber is indicated when the time is more than10 seconds. If the time taken is shorter than 10seconds. check the diaphragm for breakage andgovernor chamber for leaks and correct or re-piace the diaphragm assembly..

FIG. 3-502) Adjustment of angreich (adapter) stroke.Gradually increase the negative pressure andcheck that the control rack begins to pullfrom the point of 12.7 mm (C240) and comesto stop after the stroke of 0.8 : :. 0.05 mm(C240). 11.9 mm-C240: control rack posi-tion). If the control rack stroke deviates fromthe specified range. remove the diaphragmassembly and adjust by varying the thicknessof the angleich stroke adjusting shim.NOTE: When the diaphragm is installed. re-

peat leak test on the governor .

FIG. 3-49

FIG.3-51(2) Adjustment of pneumatic governorAdjust the points A, B. C and D with the injectionpump running at 500 r.p.m.Make an adjustment by increasing the negativepressure gradually. Hold the idling spring in freestate when making adjustment 3) Adjustment of angleich.1. Check that the control rack begins tomove from the point of A when the nega-tive pressure reaches 160 ~ 20 mm Aq(C240). If the measured value deviatesfrom the specified range. adjust with the

angleich spring adjusting shims.1) Adjustment cf smcke set screw.Hcld the gcverncr under atmcspheric pres-

sure ccnditicn and adjust setting cf the

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FU~L SYSTEM 3-19spring begins to work and turn in the idlingguide screw until the control rack just beginsto move from the point of D.

2. Further increase the negative pressureand check that the angleich strokefinishes at approximately 250 mm Aq(C240) and control rack comes to thepoint of B.If the measured value deviates from thespecified range. replace the angleichspring. (3) Adjustment of mechanica..1 governarThe mechanical governar should be test ed andadjusted by applying negative pressure at;530 .:20 mm Aq. ,4) Adjustment of hjgh-speed control. .,1. Check that the controll, rack beglns tomove from the point of C when the nega-tive pressure reaches 530 .: : 20 mm Aq -atwhich governor spring begins to work.If the measured value deviates from thespecified range. adjust with the governorspring adjusting shims.

.'"""I.i

IDLING GUIDE SCAEW

ROUNDNUTWRENCH

d>-- ~

FIG. 3-53

2. Further increase the negative pressureand check that the vacuum gauge readingis approximately 700 mm Aq (C240) whenthe control rack is pulled to the point of D.If the measured value deviates from thespecified range. replace the governorspring.

1) Adjustment of high-speed control.1. Gradually increase the pump speed andadjust setting of the governor spring ad-just bolt, so that the control rack begins topull from the point of A when the pumpspeed reaches 1950 . . 20 r.p.m. (C240). Ifcorrect adjustment cannot be obtainedonly with the adjusting bolt, further adjustwith the mechanical governor spring ad-justing shims.NOTE: Adjusting bolt has left-handthreads.

NOTE: If the thickness of the shims is var-ied or the spring is replaced in thecourse of adjustment in para-graph 3) 1 and 4) 1 and 2. settjngof angleich spring is more or lessaffected. Recheck setting of thespring and readjust as necessary.

5) Adjustment of idling position.Increase the negative pressure to approxi-mately 700 mm Aq (C240) at which the idling FIG. 3-54

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3-20 FUEL SYSTEM

an adjustment with the smoke set screw. sothat the mean injection volume is adjusted tothe range specified in the following Table3-3.ADJUSTING SHIMS

IN CASE CF ADJUSTMENT USING BCSCH OIL OL61V11Far C240:

IN CASE OF ADJsTMENT UsiNG AsTM NO. 2D DIESEL FUEL.

TABLE 3-3

2. Check that the c.ontrol rack is resting atthe position of B when the pump is run-ning at 2.090 r.p:m. (C240) and its strokebecomes shorte( than 3.5 mm when thepump speed is increased to 2,4O r.p.m.(C240). If the cohtrc rack stroke deviatesfrom the specified range. I"epla~e the gov-ernor spring.If the governor spring is replaced. repeatthe test described in the foregoing para-graph 1) and adjust as necessary.3. Check to make certain fuel flow rate isless than 3 mm3/st when the pump is run-ning at 2.400 r.p.m. (C240) with negativepressure of 530 :. ;; 0 mm Aq (C240). If themeasured value deviates from thespecified range. check the parts from theflyweights to the push-rod for wear andsetting of the pump and governor and re-piace the push-rod as necessary.If the push-rod is replaced. readjust thegovernor.

Final adjustment of injec.tion volume(Second step)2-7

(2) For operation by altitudes1) Operation of vehicle with the injection pumpadjusted to the sea level (See Table 3-3) ataltitude will be accompanied by an increasein dark exhaust smoke and rise in exhaustgas temperature due to variation in air densi-tY (Iowering of excess air ratio).The injection volume should therefore be ad-justed according to the altitude at which thevehicle is operated.2) With the pump running at 1.900 r.p.m. (C240)and with negative pressure of 530 t 20 mmAq applied to the governar chamber, makean adjustment with the smoke set screw. sothat the mean injection volume is adjusted tothe range specified in the Table 3-4 depending on the altitude at which the vehicle is tobe operated.

(1) For operation at sea level1) For operation of vehicle at the sea level. thefinal adjustment should be done accordingto the procedures below.2) With the pump running at 1.900 r.p.m. (C240)and with negative pressure of 530 . 20 mmAq applied to the governor chamber. makeIN CASE CF ADJUSTMENT USING BCSCH CIL CL61V11:Far C240: DEVIA TION

(%}INJECTION VOLUME

( c.c/1 OOOst.)L TITUDE : :.2.5+2.5I2.538.2 ~40.034.9 ~36.531.7 ~33.2

1,000 m or more2,000 m or more3.000 m or moreIN CASE OF ADJUSTMENT USING ASTM NO. 2D DIESEL FUEL

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FUEL SYSTEM 3-21

SERVICING OF AUTOMATIC TIMER,

FIG. 3-57

Disassembly and inspection ofautomatic timer3-1(1) Disassembly1) Clamp the base (57924-162) in a vise and in-stall the automatic timer assembly on thebase by fitting the pins on the base into the

holes in the flyweights.

(2) Inspection

FIG.3-58

Testing of automatic timer necessitates the useof essential instruments such as an injectionpump tester, strobo scope, etc.However, if disassembled parts are found to beout of normal condition, it is an indication thatthe characteristics of the automatic timer ismore or less affected.Check the following parts and correct or replaceas necessary .1) Check the pins on the flyweight holder andflyweight holes for wear, then check fit of

pins to the flyweight holder.2) Check the flyweight stopper for wear ordistortion.3) Check the timer springs for weakening orbreakage. If the timer spring is found to bedefective, replace both of the springs at atime together with the adjusting washers as

2) Flatten out the lock washer and remove thenut.3) Remove the lock washer, plain washer, ad-justing washer and thrust bearing.4) Remove the pump drive gear.5) Raise the flange and remove the timersprings from the flyweight holder.

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3-22 FUEL SYSTEM

the tension of the springs are factory-adjusted with the WaSher5.4) Check the parts for blnding and correct orreplace as necessary.Reassembly of automatic timer

Install the flyweights into the flyweight holderafter lubricatin9 flyweight.pins nd curved faceof the flyweights with grease.Install the timer 5pring on the spring 5eat face ofthe holder pin and support it in position of in-stallation by inserting supporter (57932-020)under the spring. (Install the adjusting washeron the spring seat before ingta~'the timerspring.}

FIG.3-61(6) Install the pump drive gear

Testing of automatic timer-3Install the automatic timer on the injection pump andmake a test using a pump tester and strobo scope(5783-002).(1) Installation of pointer and graduation plate8ond the graduation plate (57951-020) to thecoupling assembly (5784-004). then remove thetimer lock nut and install the pointer (57840-130)in position corresponding to the graduation

plate. ,c,

FIG. 3-60ge assembly installationInstall the flange assembly by aligning the notchline on the outer circumference of the flangewith the key groove in the flyweight holder. theninstall the thrust bearing and guide bushing(57924-180).1) Insert the boss on the special wrench(57916-432) into the hole in the driving flangeand install the thrust bushing (57924-190).2) Wit~ the 5pecial wrench. turn the flange indirection to compress the timer 5pring. Re-move the supporter and hold the 5prings re-leased then, install the thru5t bushing.3) Insert a screwdriver into the clearance be-tween the flange case and flyweight holderand 5et the sprjng in position between thespring seat on the holder pin and on the

flange side.of nutRemove the nut. washer guide bushing and5pecial wrench, then instaJI the adjustingwasher and lack washer in the order described.Tighten the nut and lock it with the lock nut.

NOTE: Install needle roller bearing. so that rol-lers are faced to the flange.

FIG. 3-62(2) Connection of strobo scope to injection pump1) Remove the injection pump tappet chambercover and install the synchronizer(57830-012) on the pump using the tappetchamber cover bolt holes, then bring thelever into contact with the tappet guide.Tighten the bolts using care not to bring thelever into contact with the lower spring seat.2) Loosen the nut and remove the synchronizercover, then adjust the synchronizer point gapto 0.05-0.15 mm with the tappet set to deadcenter by tilting the synchronizer.When a correct gap is obtained, install thenut and cover .3) Connect the synchronizer cable to the..Input" terminai of the amplifier (57830-052)and strobo lamp cable (57840-042) to the..LAMP'. terminai, respectively.

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FUEL SYSTEM 3-23(3) Testing of advance angle SERVICING OF FEED PUMP.

4-1 Disassembly of feed pump) Drive the injectior pump and turn thechange-over switch.on the amplifier to ..Con-tact.. from "Off.. position.2) Keep the injection pump running at speedapproximately 100 r.p.m. below the speed atWhich the automatic timer begjns to workand aim the purJ1P tester flywheel with the~trobo lighi and determine the zero point onthe dia plate attached to the flywheel.

(1) Joint bolt removalRemove the joint bolts and take out the gauzefilter from the inlet side joint.To remove the gauze filter. screw it out from thejoint bolt using a screwdriver.t,

NOTE: When test is completed, turn oH theamplifier change-over switch, thenstop the injection pump.

FIG. 3-64(2) Check valve removal1) Remove the priming pump and out(et side

nipple joint.2} Remove the check valves and valve springs.(3) Piston removal1} Remove the screw plug together with thegasket.2} Remove the piston and spring.

(4) Tappet removalPull out the snap ring and remove the tappetassembly.

1. DUST COVER2. JOINT SOL T3. GASKET4. NIPPLE5. SPRING6. CHECK VALVE7. GASKET8. HOUSING9. PIN10. ROLLER11. TAPPET GUiDE

12. T APPET13. SNAP RING14. GASKET15. JOINT BOL T. GAUZE FIL TER16. PUSH ROO17. PISTON18. SPRING19. GASKET20. PLUG SCREW21. PRIMING PUMP

FIG.3-65IG. 3-63

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3-24 FUEL SYSTEM

Inspection and reassembly offeed pttmp of the nipples, piston chamber plugs and prim-ing pump.A small amount of air leaks from the clearanceb.etween the push-rod and pump housing isnormal. However. the maximum amount of leak-age is limited to 30 cc/min (size of air bubbles5;hould not be greater than about 1 mm indiameter and the feed pump housing should bereplaced if ~the air leakage is serious and size ofajr bLibbfes is greater than the above-mentionedvalue). -

(2) Suctjon test1) Mount the feed pump to the injection pumpand connect to the joint nipple on the intakeside a tube sizing 8 mm in the inside diame-ter and 2 m in length and turn the primingpump handle ali way in.2) Position a suitable vessel filled with keroseneon a level 1 m below the feed pump and leadthe loose end of the tube into the vessel.Operate the injection pump at 80 r.p.m. andsee if fuel is sucked in and pumped outwithin 60 seconds.If the time needed for fue( delivery is longerthan 120 seconds, it indicates that the pumpis in need of correction.

(1) Inspectjon1.) Check the gauze filter for restrictions andwash clean as necessary. Replace the filter.with a new one if found to be damaged.2) Check vaJve..1. CheGk the seating face for step wear or" cracking and replace the check valve witha new one if wear or damage is beyondcorrection. Check valve with slight stepwear can be corrected by lapping on aglass sheet using fine lapping compound.2. Check the valve seat in the housing fordistortion or damage and replace thebody if found to be defective.3. Check the valve spring for cracking, dis-tortion or damage and replace asnecessary.3) Check operation of the priming pump handleand replace if its movement is unsmooth.4) Check the piston for cracking or scuffs andreplace if any abnormal condition isnoticeable.5) Check the push-rod for wear or damage.6) Check the tappet roller and pin for abnormalwear or cracking and replace as necessary.Assemble the pin to the roller and check forlooseness of fjt and replace if an excess playis noticeable.7) Check the threaded portions of the housingfor damage and replace as necessary.

(3) Priming pump suction testOperate the priming pump handle at the speedof 60 -100 times/minutes. if the kerosene issucked into the pump and forced out within 60times. the priming pump is in normfll function. Ifmore than 120 times are required, jt indicate~the need for service attention.

(2} ReassemblyTo reassemble, f0110W the disassembly proCe-dure in reverse order and note the f0110wing:1) Apply engine oil to the sliding face of theparts before reassembling.2} Install the pUSh-rod into the housing. So thatits end with heavy chamfering is turned tothe piston.3) Install the piston into the housing with itsconcaved face turned to the pUSh-rod.Testing of feed pump

(4) Delivery test1) Connect the pipe as described in suction testand support the tube connected to the outletside of the feed pump on a level 1 m abovethe pump and lead the free end of the tubeinto a measuring cylinder with the capacityof about 500 cc.2) Operate the injection pump at 1000 r.p.m.and adjust the pressure of delivery to 1.6kg/cm2 and measure the amount of fuelpumped out into the measuring cylinderwithin the period of 15 seconds. The feedpump is normal if the amount of fuel pumpedout into the measuring cylinder is more than300 cc. The feed pump is in need of overhaul-ing if the amount of fuel delivery is less than200 cc.

hen reassembly of the feed pump parts is com-pleted, make a performance test in the followjngparticulars:(1) Oilleakage testTurn the priming pump handle ali way in andplug the fuel oCItlet side. Apply compressed ajr 2kg/cm2 into the pump from the intake port andsubmerge the pump in clean kerosene andcheck for leaks. Correction is necessary if airbubbles arise from around the jointing portion

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FUEL SYSTEM 3-25

5. SERVICING OF INJECTION NOZZLESANO NOZZLE HOLDERS

" 1. BOOY'2. CYCRON BLAOE" 3. ELEMENT

i 4. OUST PAN -5. WING NUT

I~~ ..3.-\

1. JOINT SOL~2. OVERFLOW VALVE3. JOINT SOL T4. JOINT SOt:.T5. COVER6. ELEMENT

~ .-: ' }~.-IO-~ ---?

r

-1. JOINTBOLT2. GASKET3. SCREW CAP NUT4. GASKET5. AOJUSTING SCREW6. NUT

..7. GASKETli \ .J 8. WASHER, 17 9. NOZZLE SPRING.10. PUSH-ROD11. NOZZLE SPRING12. SCREW NOZZLE HOLDER13. NOZZLE14. NOZZLE NUT15. WASHER16. CONNECTOR17. EDGEFILTER

FJG. 3-66Disassembly

~ "I

12-- )IJ--~

I.~

Clean the internai part of the nozzle body inkerosene by using a piece of wood.(1) Visual inspectionAfter washing. check the injection nozzlesagainst the following:

1) Needle valves.Check the valve seats. guide shafts and injec-tion shaft for damage. ;2) Nozzle body.Check the valve seats for carbon deposjt and,damage. AIso check the injection orifices fbruneven wear.Replace both of the parts by using an as-sembly even if either of the needle valve orthe nozzle body is found to be defective.(2) Sliding testA sliding test should be made on the entire in-jection nozzles often visual inspection.

Hold the nozzle body vertically and pull the nee-dle valve upward about 1/3 of its entire lengthand release it and see if it lowers onto its seat byits own weight.If lowering of the needle valve is unsmooth.check for presence of foreign matter and repeatthe test.If the trouble persists, replace the entire nozzleassembly with a new one.(3) Testing of injection nozzles on nozzle testerMake the following tests by using a nozzletester.a. Injection starting pressure.b. Spray pattern and operating noise.

...-.

lii-~

Ii a'11.1 : .DIESEL KIKIPART NUMBERART NAME

Nozzle tester-- 5785-050

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3-26 FUEL "SYSTEM

SERVICING OF FUEL FIL TER.) Testing standard and reassembly of nozzleparts.Clean the fuel tank on the tester. fuel pipe.nozzle nut and testirig nozzle and use onlyclean kerosene (specific gravity: 0.82-0.84)in the tester after filtering to be sure it isabsolutely free from foreign matters. Wheninserting the nozzle into the nozzfe nut checkthe contact faces for damage and presenceof foreign matters. Make sure to install thenozzle on the tester after turning loose thespring adjusting screw sufficiently.

1. JOINT SOLT2. OVERFLOW VALVE3. JOINT SOL T4. JOINTSOLT5. COVER6. ELEMENTFIG. 3-68

Fuel filter service procedure-1The fuel filter is of a cartridge type and cannot bedisassembled. The entire fuel filter assembly shouldtherefore be replaced.(1) DrainingDrain the filter element every 6000 km by remov-ing the element assembly.(2) EJement replacementReplace the element assembly every 18000 km.(3) Element installationApply oil to the gasket and instaLI the element.

When the element is se.ated on the sea'ing face.further turn the element 2/3 of a turn with hand.NOTE: When fuel filter is installed. bleed thefuel circuit. Then start the engine andcheck the sealing face for fuel leaks.(4) Inspection of overflow valveCheck the seating face of the ball and seat forwear and spring for weakening or damage andreplace the entire overflow valve assembly if anyabnormal condition is noticeable.

When the nozzle assembly is installed on thetester, operate the hand lever 2 or 3 times tosee if the nozzle is properly set in position.If the joints are free from leaks and the nee-dJe valve is working normally, the operationof the nozzle will be accompanied by whistl:-ing sound.2) Injection starting pressure test (standardpressure: 120 kg/cm2).Adjust the standard pressure by means of thespring adjusting screw.3) Spray testInstall the injection nozzle assembly on thetester and operate the tester severaJ timesand visuaJly check the spray patterns againstthe following. Replace the nozzle assembly iffound to be out of normal operating condi-tion. The pressure gauge should be held outof function when making spray test.1. Spray should be free from coarse

particles.2. Spray pattern should be uniform and freefrom spattering.3. Nozzle should be free from dropping.4) Testing precautions1. Exercise extreme care to avoid bringingthe fuel sprayed from the nozzle on thetester into direct contact with your hands.as the sprayed fuel particies will penetratedeeply into the skin and cause damage tothe tissues and leading to blood poison-ing. if allowed into blood vessels.2. Use only new and clean kerosene in thetester and keep the surrounding free fromdirt. dusts and other foreign matters.3. Test the pressure gauge once a monthand if the indication is not accurate, re-piace the gauge or piace a correctiontable on the page.

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FUEL SYSTEM 3-277. TROUBLE SHOOTING