Yanmar 2YM15 Service Manual Page 1

M9961-03E1013YM30/3YM20/2YM15

FOR SAFETY1. SAFETY LABELS• Most accidents are caused by negligence of basic safety rules and precautions. For accidentprevention, it is important to

4. Disassembly and reassembly80(7) Removing the alternator1) Loosen the set bolt (belt adjuster bolt) and movethe alternator downwards. Loosen the V-

4. Disassembly and reassembly81(9) Removing the heat exchanger (exhaust manifold, coolant tank unit)Remove the heat exchanger and gasket packing from

4. Disassembly and reassembly82(13)Removing the fuel injection pipe1) Remove the fuel injection pipe retainer. 2) Loosen the cap nuts on both ends of

4. Disassembly and reassembly83(15)Removing the fuel injection nozzlesLoosen the fuel nozzles and remove them from thecylinder head.(16)Remove the fu

4. Disassembly and reassembly84(17)Removing the rocker arm shaft assembly1) Loosen the hexagon head bolts and remove therocker arm cover.Note:Don&apo

4. Disassembly and reassembly85R1(21)Turning the engine over1) Place a wood block of appropriate size on the floor,and stand up the engine on the fly

4. Disassembly and reassembly86(26)Removing the lube oil pumpRemove the lube oil pump from the gear case cover.(27)Removing the idle gearLoosen the t

4. Disassembly and reassembly87(30) Removing the gear case 1) Remove the gear case from the cylinder block.2) Remove the O-rings from the lube oil pa

4. Disassembly and reassembly88(34)Removing the main bearing1) Remove the main bearing bolts.2) Remove the main bearing cap and lower mainbearing met

4. Disassembly and reassembly894.3.2 Reassembly(1) Clean all partsClean all parts using by the cloth and diesel oil (or cleaning agent) before reasse

2. Safety Precautions(1) SERVICE AREA• Sufficient Ventilation Inhalation of exhaust fumes and dust particles may be hazardous to oneshealth. Running

4. Disassembly and reassembly90(5) Mounting the main bearing capCoat the lower main bearing metal with engine oil, andmount it to the main bearing ca

4. Disassembly and reassembly91R1(7) Turning the engine overStand up the engine on the flywheel housing.(8) Mounting the gear caseApply the liquid ga

4. Disassembly and reassembly92R12) Coat the outside of the piston and the inside of theconnecting rod crank pin metal with engine oil andinsert the

4. Disassembly and reassembly93(11) Mounting the idling gear1) Mount the idling gear so that the mark of the idlegear shaft upward.2) Align the "

4. Disassembly and reassembly94R1(13) Mounting the oil seal and gear case cover1) Replace the used oil seal with a new one when thegear case cover is

4. Disassembly and reassembly95R1(15) Mounting the oil pan spacer and the oil pan1) Apply the liquid gasket to the surfaces of the gearcase cover, ge

4. Disassembly and reassembly96R1(19) Mounting the marine gearbox1) Mount the damper disk to the flywheel.Align the damper disk with the input shaft

4. Disassembly and reassembly97(22) Mounting the fuel injection pump1) Lightly fit the fuel injection pump on the gear case.(After adjusting injectio

4. Disassembly and reassembly98(24) Mounting the fresh water pump1) Thoroughly coat both sides of the gasket withadhesive.2) Renew the O-ring for the

4. Disassembly and reassembly99(26) Mounting the lube oil filter.Mount the lube oil filter with the tool of the filter caseremover.(27) Mounting the

(2) WORK - WEAR (GARMENTS)• Safe Work ClothingAppropriate safety wear (gloves, special shoes/boots, eye/ear protection,head gear, harness', cloth

4. Disassembly and reassembly100R1(29) Mounting the mixing elbow1) Mount the mixing elbow on the exhaust manifold outlet.2) Mount the cooing seawater

4. Disassembly and reassembly101(31) Mounting the alternator1) Mount the bracket on the cylinder head and theadjuster on the gear case cover, and the

4. Disassembly and reassembly102(34) Mounting the fuel filter and fuel pipe1) Mount the fuel filter on the bracket, which is tightened to the cylinde

4. Disassembly and reassembly103R1(38) Filling with cooling water1) Open the coolant (fresh water) tank cap and fill with water.2) Fill with water un

5. Inspection and servicing of basic engine parts1045. Inspection and servicing of basic engine parts5.1 Cylinder blockThe cylinder block is a thin-

5. Inspection and servicing of basic engine parts105R15.1.4 Replacement of cap plugsStepNo.Description Procedure Tool of material used1 Clean and rem

5. Inspection and servicing of basic engine parts106R15.1.5 Cylinder bore measurementEspecially clean head surface, cylinder bores and oilholes, and

5. Inspection and servicing of basic engine parts1075.2 Cylinder headThe cylinder head is of 3-cylinder integral construction, mounted with 14 bolts.

5. Inspection and servicing of basic engine parts1085.2.1 Inspecting the cylinder headThe cylinder head is subjected to very severe operating conditi

5. Inspection and servicing of basic engine parts1095.2.2 Valve seat correction procedureThe most common method for correcting unevennessof the seat

(5) FASTENER TORQUE• Torquing FastenersAlways follow the torque values and procedures as designated in theservice manual. Incorrect values, procedures

5. Inspection and servicing of basic engine parts110R15.2.3 Intake/exhaust valves, valve guides(1) Wearing and corrosion of valve stemReplace the val

5. Inspection and servicing of basic engine parts111(4) Valve guide1) Measuring inside diameter of valve guide.Measure the inside diameter of the val

5. Inspection and servicing of basic engine parts112R14) Valve stem sealsThe valve stem seals in the intake/exhaust valveguides cannot be re-used. Wh

5. Inspection and servicing of basic engine parts113R14) Measure spring tension.5) Assembling valve springs. NOTE: The pitch of the valve spring is n

5. Inspection and servicing of basic engine parts114R15.2.6 Measuring top clearance(1) Place a high quality fuse (Ø1.5 mm, 10 mm long) in three posit

5. Inspection and servicing of basic engine parts1155.2.8 Adjustment of valve clearance(1) Make adjustments when the engine is cool.(Refer to 2.2.2(8

5. Inspection and servicing of basic engine parts116R15.3 Piston and piston pinsPistons are made of a special light alloy with superiorthermal expans

5. Inspection and servicing of basic engine parts117R1(3) Removing the piston pinA floating type piston pin is used in this engine. The piston pin ca

5. Inspection and servicing of basic engine parts118R15.3.3 Piston ringsThere are two compression rings and one oil ring.The absence of an oil ring o

5. Inspection and servicing of basic engine parts119R1(2) Measuring piston ring gapPress the piston ring onto a piston liner and measurethe piston ri

(8) FURTHER PRECAUTIONS• Fueling / RefuelingKeep sparks, open flames or any other form of ignition (match, cigarette,etc.) away when fueling/refuelin

5. Inspection and servicing of basic engine parts1205) The oil ring is provided with a coil expander. Thecoil expander joint should be opposite (stag

5. Inspection and servicing of basic engine parts1215.4 Connecting rodThe connecting rod is made of high-strength forgedcarbon steel.The large end wi

5. Inspection and servicing of basic engine parts122R1(2) Checking the side clearance of a connectingrodFit the respective crank pins to the connecti

5. Inspection and servicing of basic engine parts123• Other procedure of measuring crank pin oil clearance1) Use the press gauge (Plastic gauge) form

5. Inspection and servicing of basic engine parts124R15.4.3 Piston pin bushing(1) Measuring piston pin clearance.Excessive piston pin bushing wear ma

5. Inspection and servicing of basic engine parts125R15.5 Crankshaft and main bearingThe crank pin and crank journal have been inductionhardened for

5. Inspection and servicing of basic engine parts126R1(3) Measuring the crank pin and journalMeasure the outside diameter, roundness and taper ateach

5. Inspection and servicing of basic engine parts127R1(4) Checking the side gap of a crankshaftAfter assembling the crankshaft, tighten the mainbeari

5. Inspection and servicing of basic engine parts128R15.6 Camshaft and tappets5.6.1 CamshaftThe camshaft is normalized and the cam and bearingsurface

5. Inspection and servicing of basic engine parts129(3) Camshaft and bearing hole measurementMeasure the camshaft outside diameter with amicrometer.

3. Precautions for Service Work(1) Precautions for SafetyRead the safety precautions given at the beginning of this manual carefully and always mind

5. Inspection and servicing of basic engine parts130R15.6.2 Tappets(1) The tappets are offset to rotate duringoperation and thereby prevent unevenwea

5. Inspection and servicing of basic engine parts131R15.7 Timing gearThe timing gear is helical type for minimum noise and specially treated for high

5. Inspection and servicing of basic engine parts1325.8 Flywheel and housingThe function of the flywheel is through inertia, to rotate the crankshaft

5. Inspection and servicing of basic engine parts1335.8.2 Damper disc(1) Spline partWhenever uneven wear and/or scratches are found,replace with new

6. Fuel injection equipment134R16. Fuel injection equipment6.1 Fuel Injection pump/governorRefer to the service manual of the YPES-ML fuel injection

6. Fuel injection equipment135R16.1.2 Fuel injection pump service data and adjustment(1) Service data1) Service data for 3YM30Note : The value in par

6. Fuel injection equipment2) Service data for 3YM20Note : The value in parentheses is a reference value.Part code (Back No.) - 728890-51300 (TMM1)Adj

6. Fuel injection equipment3) Service data for 2YM15Note : The value in parentheses is a reference value.Part code (Back No.) - 728890-51300 (TMM1)Adj

6. Fuel injection equipment137R1(2) Fuel adjustment procedure• Fuel adjustment for 3YM30 and 2YM151) Loosen the nut of the FO limiter, and screw thead

6. Fuel injection equipment138R1• Fuel adjustment for 3YM201) Loosen the nut of the FO limiter, and screw theadjusting bolt to the bottom. Tighten the

1. General1R11. General1.1 Exterior views<Note> This illustration shows the 3YM30 with Yanmar marine gear (Model:KM2P-1).Operating SideIntake s

6. Fuel injection equipment1396.1.3 Fuel injection pump structureSection of a fuel injection pump/ governor for 3YM30.

6. Fuel injection equipment1406.1.4 Removing a fuel injection pumpThe procedure to remove a fuel injection pump from the gear case is shown.[NOTICE]Be

6. Fuel injection equipment1416.1.7 Troubleshooting of fuel injection pumpComplete repair means not only replacing defective parts, but finding and el

6. Fuel injection equipment142Fault Cause Remedy2. Engine starts, but immediately stops.(1) Fuel pipe is clogged.(2) Fuel filter is clogged.(3) Improp

6. Fuel injection equipment143Fault Cause Remedy7. Loud knocking. (1) Injection timing is too fast or too slow.(2) Injection from nozzle is improper.

6. Fuel injection equipment144R16.2 Fuel feed pumpThe fuel feed pump feeds fuel from the fuel tank,passes it through the fuel filter element, and supp

6. Fuel injection equipment145R16.2.3 Disassembly and reassembly of fuel feed pump(1) Disassembly1) Remove the fuel feed pump mounting nut, and take t

6. Fuel injection equipment146R1(4) Valve contact/mountingClean the valve seat and valve with air to remove anyforeign matter.(5) Inspect the diaphrag

6. Fuel injection equipment147R16.3 Fuel filterThe fuel filter is installed between the feed pump andinjection pump, and serves to remove dirt and imp

6. Fuel injection equipment1486.4 Fuel tankA triangular 30 liter fuel tank with a 2000mm (78.7402 in.) rubber fuel hose to fit all models is available

1. General21.2 SpecificationsOfficial engine model name unit 3YM30 3YM20Company internal model name- 3YM30 3YM30C 3YM20 3YM20CMarine gear model - KM2P

7. Intake and exhaust system1497. Intake and exhaust system7.1 Intake systemAir enters in the intake silencer mounted at the end ofthe intake manifo

7. Intake and exhaust system150[NOTICE]1) When a diaphragm is damaged, pressure control inside the crankcase becomes insufficient, andtroubles occur.

7. Intake and exhaust system151R17.2 Exhaust system7.2.1 ConstructionThere are two types of mixing elbows, the L-type and the U-type. The mixing elbo

8. Lubrication system152R18. Lubrication system8.1 Lubrication systemThe lube oil in the oil pan is pumped up through the intake filter and intake pi

8. Lubrication system153R18.2 Lube oil pump8.2.1 Lube oil pump constructionThe trochoid type lube oil pump is mounted in the gearcase cover, and the

8. Lubrication system1548.2.4 Lube oil pump inspection(1) Outside diameter clearance and side clearance of outer rotorInsert a gap gauge between the

8. Lubrication system1558.3 Lube oil filter8.3.1 Lube oil filter constructionThe lube oil filter is a full-flow paper element typemounted to the side

8. Lubrication system1568.4 Rotary waste oil pump (Optional)A rotary waste oil pump to pump out waste oil isavailable as an option.Rotary waste oil p

9. Cooling water system157R19. Cooling water system9.1 Cooling water systemThe cooling water system is of the indirect seawater cooled, fresh water

9. Cooling water system158R1Cooling water lineHeat exchange(Cooling water pipes)Mixing elbowExhaust manifoldCoolant tankFresh water pumpFrom seacockS

1. GeneralOfficial engine model name unit 2YM15Company internal model name- 2YM15 2YM15CMarine gear model - KM2P-1 SD20Use - Pleasure use Type - Vert

9. Cooling water system159R19.2 Seawater pumpThe seawater pump is driven by a V-belt. 9.2.1 Specifications of seawater pumpPerformance9.2.2 Seawater

9. Cooling water system1609.2.3 Seawater pump Inspection(Refer to 2.2.4(5).)(1) Inspect the rubber impeller, checking for splitting around the outsid

9. Cooling water system1619.2.4 Seawater pump reassembly(1) When replacing the oil seal, coat with grease and insert.(2) Mount the pump shaft, ball b

9. Cooling water system1629.3 Fresh water pump9.3.1 Fresh water pump constructionThe fresh water pump is of the centrifugal (volute) type, and circu

9. Cooling water system163R19.3.3 Fresh water pump disassembly(1) Do not disassemble the fresh water pump. It is difficult to disassemble and, oncedi

9. Cooling water system164Measuring side clearance between impeller and plate.mmStandard LimitSide clearance between impeller and plate0.5 -Straighte

9. Cooling water system1659.4 Heat exchanger9.4.1 Heat exchanger constructionThe heat exchanger cools the hot fresh water, that hascooled the inside

9. Cooling water system1669.5 Pressure cap and coolant recovery tank9.5.1 Pressure cap constructionThe pressure cap mounted on the filler neckincorpo

9. Cooling water system1679.5.4 Replacing filler neck1) Take out the copper pipe inside the filler neck with striking a circumference with a driver a

9. Cooling water system1689.5.5 Function of the coolant recovery tankThe pressure valve opens to discharge steam when thesteam pressure in the fresh

1. General3 (Note)1. Rating condition : ISO 3046-1, 86652. 1HP (metric horse power) ≒ 0.7355 kW3. Fuel condition : Density at 15°C = 0.842* Fuel tempe

9. Cooling water system1699.6 Thermostat9.6.1 Functioning of thermostatThe thermostat opens and closes a valve according to changes in the temperatur

9. Cooling water system1709.7 Bilge pump and bilge strainer (Optional)9.7.1 Introduction(1) General Introduction(2) ExteriorName Bilge pumpTime 10 mi

9. Cooling water system171R19.7.2 Description(1) Characteristics1) Discharge at lift : 0 m discharge capacity : 20 liters/min. or greater.2) Automati

9. Cooling water system172R1(7) The pump cannot be used to drain off rain water or large amounts of flood water. Thepump can be run continuously for

9. Cooling water system173R1(4) Attaching the delivery nozzle (outlet)• Make a fixing hole of Ø21 or less for attaching thenozzle. The hose attached

9. Cooling water system1749.7.5 Cautions for assemblingObserve the following cautions for handling.• Do not use gasoline or solvents.1) gasoline 2) e

9. Cooling water system1759.7.6 TroubleshootingRefer to the following countermeasures for difficulties that arise.Problem Cause Countermeasure1. Pump

10. Reduction and reversing gear176R110. Reduction and reversing gearMarine gear KM2P-1 is applied to the 3YM30, 3YM20 and 2YM15 series engines.Refer

11. Remote control (Optional)177R111. Remote control (Optional)11.1 Remote control system11.1.1 Construction of remote control systemThe remote contr

11. Remote control (Optional)178(2) Remote control cableUse only Super Responsive Morse Control Cables.These are designed specifically for use with M

Printed in JapanM9961-03E101Publication No. M9961-03E101History of RevisionManual Name Service Manual for Marine Diesel EngineEngine Model: 3YM30/3YM2

1. General4R11.3 Fuel oil, lubricating oil and cooling water1.3.1 Fuel oilIMPORTANT:Only use the recommended fuel to obtain the best engine performanc

11. Remote control (Optional)17911.2 Remote control installation(1) Speed controlRemote control handle (MT-3)Remote control handle (MN)OptionalClampC

11. Remote control (Optional)180(2) Clutch control(3) Engine stopUsually, when an engine is stopped, the stop button ofan instrument panel is pushed,

11. Remote control (Optional)181R111.3 Remote control inspection(1) When the control lever movement does notcoincide with operation of the engine, ch

11. Remote control (Optional)18211.4 Remote control adjustment(1) Shift lever adjustmentMove the lever several times-the movement of the clutch lever

12. Electrical system18312. Electrical system12.1 Electrical system020103040GLOWBOFFONSTARTSTOP50Battery switchBatteryAlternator(Fitting to marine ge

12. Electrical System18412.1.1 Wiring diagramFor B-type instrument panel-+Starter relayC.W. temp. switch Eng. oil pressure switchSail drive only for s

12. Electrical System18512.2 BatteryThe new type instrument panels are applied for 3YM30 series engines. The features are compactness,waterproof and i

12. Electrical System18612.3 Starting motorA starting motor turns the ring gear installed on a engine flywheel by the pinion while overcomingresistanc

12. Electrical System18712.3.3 Structure(1) Disassembly drawingMagnetic switchInternal gearBracketPinionGear housingArmatureYokeRear cover

12. Electrical System188(2) StructureWhen the starting switch is turned on, a magnet switch takes a voltage, and a pinion projects. The pinionengages

1. General5(2) Selection of marine gear lube oilUse the following engine oil• API classification ... CD or better(Standards of America Petroleum

12. Electrical System18912.4 Alternator standard, 12V/60AThe alternator serves to keep the battery constantly charged. It is installed on the cylinder

12. Electrical System19012.4.2 Structure(1) Disassembly drawing(2) Structure(12V60A alternator)PulleyFront bracketRotorStatorFanBall bearingRear brack

12. Electrical System19112.4.3 Wiring diagram[NOTICE]1) Don't do mis-connecting and short-circuit of each terminal.2) Don't remove a battery

12. Electrical System19212.4.5 Inspection(1) V belt inspection1) Inspect the matter whether there are not crack,stickiness and wear on the belt visual

12. Electrical System19312.5 Alternator 12V/80A (Optional)12.5.1 SpecificationsYanmar code 119573-77201Model of alternator LR180-03C (HITACHI)Model of

12. Electrical System19412.5.2 StructureDisassembly drawing and StructureFanFront coverBearing retainerStatorBrush regulator assyDiodeCondenserRotorBa

12. Electrical System19512.5.3 Wiring diagram [NOTICE]1) Don't do mis-connecting and short-circuit of each terminal.2) Don't remove a batter

12. Electrical System196R112.6 Instrument panelThe new type instrument panels are applied for 3YM30/3YM20/2YM15 series engines. The features arecompac

12. Electrical System19712.7 Warning devices12.7.1 Oil pressure alarmIf the engine oil pressure is below 0.01-0.03 MPa (0.1-0.3 kgf/cm2, 1.42-4.26 lb/

12. Electrical System198Inspection12.7.2 Cooling water temperature alarmA water temperature lamp and a water temperature switch (thermo switch), backe

1.General1.4 Engine outline(1) 3YM30 (with KM2P-1 marine gear)6R1

12. Electrical System19912.8 Glow plugA glow plug is available for warming intake air whenstarting in cold areas in winter. The glow plug ismounted to

12. Electrical System20012.9 Electric engine stopping deviceThe electric engine stop device is fitted to the governor.The device is operated by the st

13. Service standards201R113. Service standards13.1 Engine tuningNo. Inspection item Standard LimitReferencepage1Intake/exhaust valve clearancemm0.15

13. Service standards20213.2 Engine body13.2.1 Cylinder head(1) Cylinder head(2) Intake/exhaust valve and guide(3) Valve spring(4) Rocker arm and sha

13. Service standards203R1(5) Tappet and push rod13.2.2 Camshaft and gear train (1) Camshaft(2) Idle gear shaft and bushing(3) Backlash of each gearm

13. Service standards204R113.2.3 Cylinder block(1) Cylinder block(2) Crankshaft(3) Thrust bearingmmInspection item Standard LimitReference pageCylind

13. Service standards205R1(4) Piston and ring1) Piston2) Piston ringmmInspection item Standard LimitReference pagePiston outside diameter (Measure in

13. Service standards206R1(5) Connecting rod1) Rod big end2) Rod small end3YM20/2YM15 mmInspection item Standard LimitReference pageTop ring Groove w

13. Service standards20713.3 Lubricating oil system (Trochoid pump)(1) Outside clearance of outer rotor(2) Tip clearance between outer rotor and inne

14. Tightening torque for bolts and nuts20814. Tightening torque for bolts and nuts14.1 Main bolt and nut14.2 Standard bolts and nuts (without lube o

1.General(2) 3YM30C (with SD20 sail drive)7R1

3YM30/3YM20/2YM15SERVICE MANUALCode No. M9961-03E101First Edition : March 20042nd Edition : April 2005Published by : Quality Control Dept. Marine Fac

YANMAR MARINE INTERNATIONAL B.V.P.O. BOX 30112,1303AC ALMERE, THE NETHERLANDSBRUGPLEIN 11, 1332 BS ALMERE-DE VAART, THE NETHERLANDSPHONE: 31 36-549321

1.General(3) 3YM20 (with KM2P-1 marine gear)8

1.General9R1(4) 3YM20C (with SD20 sail drive)NOTE1. DWG. SHOWS MOUNTING BLOCKS AT ORIGINAL HEIGHT.2. ENGINE WEIGHT WILL COMPRESS BLOCKS BY 4.5 mm (APP

1.General(5) 2YM15 (with KM2P-1 marine gear)9-2R1

1.General(6) 2YM15C (with SD20 sail drive)1859-3R1

1.General1.5 Piping diagrams(1) 3YM30/3YM20 (with KM2P-1 marine gear)OverflowFuel oil inletFuel feed pumpLubricating oil filter (cartridge type)Mixing

1.General11(2) 3YM30C/3YM20C (with sale drive SD20)OverflowFuel oil inletFuel feed pumpLubricating oil filter (cartridge type)Mixing elbowCheck valveC

FOREWORDThis service manual has been complied for engineers engaged in sales, service, inspection andmaintenance. Accordingly, descriptions of the con

1.General(3) 2YM15 (with KM2P-1 marine gear)11-2R1

1.General11-3R1(4) 2YM15C (with sale drive SD20)

1.General12R11.6 Exhaust gas emission regulation3YM30/3YM20/2YM15 series engines are applicable with Off-road Compression Ignition enginesregulations

1.General131.6.2 Exhaust gas emission standard (EPA/ARB)Note1. The transit smoke (ACC/LUG/PEAK) is not applicable.2. The EPA recommended fuel is used.

1.General14(5) Quality guarantee period for exhaust emission related partsFor exhaust emission related parts, follow the inspections outlined in the &

2. Inspection and adjustment15R12. Inspection and adjustment2.1 Periodic maintenance scheduleThe engine periodic inspection timing is hard to determi

2. Inspection and adjustment16R1*2 Whichever comes first { : User-maintenance Å : Parts replacement z : Shop-inspectionSystem ItemBeforestarting*2

2. Inspection and adjustment17R12.2 Periodic inspection and maintenance procedure2.2.1 Check before startingBe sure to check the following points bef

2. Inspection and adjustment18R12) Checking marine gear lube oil levela) Check the lube oil level of the marine gear with adipstick.b) When the level

2. Inspection and adjustment19IMPORTANT:If the cooling water runs short quickly or when the coolant tank runs short of water with the coolantrecovery

CONTENTS1. General ... 11.1

2. Inspection and adjustment202.2.2 inspection after initial 50 hours or one month operationBe sure to check the following points after initial 50 h

2. Inspection and adjustment21R13) Moisten the new oil filter gasket with the lube oil and install a new lube oil filter manually turning itclockwise

2. Inspection and adjustment22R1(4) Adjust the tension of the alternator drive beltWhen there is not enough tension in the V-belt, it willslip and th

2. Inspection and adjustment23(5) Adjusting the intake/exhaust valve clearanceMake measurement and adjustment while the engine is cold.1) Valve clear

2. Inspection and adjustment24b) Measure valve clearanceInsert a 0.2 mm thickness gage between therocker arm and valve cap, and adjust the valveclear

2. Inspection and adjustment25R1(7) Adjust the propeller shaft alignmentThe flexible engine mounts is compressed a little in the initial engine opera

2. Inspection and adjustment26Cylinder headBracketFuel filterFuel pipeFuel injection pumpClampFuel pipe

2. Inspection and adjustment27(2) Check the electrolyte level in the batteryFire due to electric short-circuit• Make sure to turn off the battery swi

2. Inspection and adjustment28(1) Electrolyte level• Check the level of fluid in the battery.When the amount of fluid nears the lower limit, fillwith

2. Inspection and adjustment29(b) Measurement with hydrometerWhen using a hydrometer, the measured specificgravity must be corrected according to th

3.4 Troubleshooting by measuring compression pressure ...624. Disassembly and reassembly ...

2. Inspection and adjustment30R12.2.4 Inspection every 100 hours six monthsBe sure to check the following points every 100 hours or six months opera

2. Inspection and adjustment31R12.2.6 Inspection every 250 hours or one yearBe sure to check the following points every 250 hours or one year operat

2. Inspection and adjustment32R1(3) Replace the marine gear lube oil.Refer to 2.2.2(3) for the procedure.(4) Replace the engine lube oil filter.Refer

2. Inspection and adjustment33R1(6) Replace the fresh water coolant.Be sure to replace the fresh water every year. When the long life coolant is used

2. Inspection and adjustment345) After supplying cooling water, fit the filler cap and tighten it firmly. To reassemble the cap, align thetabs on the

2. Inspection and adjustment35R1(8) Clean the exhaust/water mixing elbow.There are two types of mixing elbows, the L-type and the U-type. The mixing

2. Inspection and adjustment36R1(10) Check the wiring connectors.Check whether each connection part doesn't have loosened.020103040GLOWBOFFONSTA

2. Inspection and adjustment37R12.2.7 Inspection every 1,000 hours or four yearsBe sure to check the following points every 1,000 hours or four years

2. Inspection and adjustment38(2) Check the injection spray condition of a fuel nozzleWear protective glasses when testing injection from the fuel in

2. Inspection and adjustment39[Informative: Fuel injection valve structure]Nozzle holderPressure adjusting shimNozzle springNozzle spring seatFuel re

5.6 Camshaft and tappets ...1285.6.1 Camshaft.

2. Inspection and adjustment402) Spray pattern inspectionAfter adjustment to the specified valve opening pressure, use a nozzle tester and check the

2. Inspection and adjustment414) Nozzle punch mark(3) Check the impeller of the cooling water pump (seawater pump)The impeller must be replaced with

2. Inspection and adjustment423) Heat exchanger body water leakage testa) Compressed air/water tank testFit rubber covers on the fresh water andseawa

2. Inspection and adjustment43(5) Diaphragm assembly inspectionInspect the diaphragm assy on the rocker arm cover. 1) Loosen screws, and remove a dia

2. Inspection and adjustment442.3 Adjusting the no-load maximum or minimum speed1) After warming the engine up, gradually raise thespeed and set it a

2. Inspection and adjustment452.5 Thermostat inspection(1) Put the thermostat in a beaker with fresh water, and heat it on an electric stove. Thether

2. Inspection and adjustment462.6 Adjusting operationPerform the adjusting operation for an engine as follows after the maintenance job:2.6.1 Prelimi

2. Inspection and adjustment472.6.3 Check points and precautions during runningStep Item Instructions Precautions1 Checks before operation1) Make su

2. Inspection and adjustment482.7 Long storageObserve the following instructions when the engine is to be stored for a long period without operation:

3. Troubleshooting493. Troubleshooting3.1 Preparation before troubleshootingIf the signs of a trouble appear, it is important to lecture on the count

8.2.2 Specifications of lube oil pump ... 1538.2.3

3. Troubleshooting503.2 Quick reference chart for troubleshootingIt is important to thoroughly under stand each system and the function of all of the

3. Troubleshooting51TROUBLE AND TROUBLESHOOTING(I-1) Add fuel oil and prime.Chart 1THE ENGINE SUDDENLY STOPS.CountermeasureCause and EffectCountermea

3. Troubleshooting52Trouble and TroubleshootingTROUBLE AND TROUBLESHOOTINGCountermeasureChart 3POOR EXHAUST COLOR(I-1) Check, repair or replace.(I-

3. Troubleshooting53TROUBLE AND TROUBLESHOOTINGCause and EffectCountermeasure(IV-1) Replace.(IV-2) Clean.(IV-3) Replenish oil and check. Replace

3. Troubleshooting54TROUBLE AND TROUBLESHOOTINGCause and EffectCountermeasure(III-1) Replace.(III-2) Adjust.(III-3) Clean.(III-4) Disassemble, wa

3. Troubleshooting55(3) Sticking of valve needle(4) Faulty injection sprayTROUBLE AND TROUBLESHOOTINGCause and EffectCountermeasure(III-1) Adjust

3. Troubleshooting56TROUBLE AND TROUBLESHOOTINGCause and EffectCountermeasure(V-1) Replace plunger and barrel as a unit.(V-2) Replace.(V-3) Disas

3. Troubleshooting57TROUBLE AND TROUBLESHOOTINGCause and EffectCountermeasure(IV-1) Lap valves.(IV-2) Adjust.(IV-3) Replace.(IV-4) Replace.(IV-5)

3. Troubleshooting58TROUBLE AND TROUBLESHOOTINGCause and EffectCountermeasure(IV-1) Adjust the amount of returning water or check the co

3. Troubleshooting593.3 Troubleshooting (Concerning engine and fuel injectionequipment)Malfunctions Causes RemediesThe engine does not operate1. Fu

9.7 Bilge pump and bilge strainer (Optional) ...1709.7.1 Introduction ...

3. Troubleshooting60Malfunctions Causes RemediesThe engine exhaust contains smoke and the engine “knocks”1. The injection timing is incorrect2. The n

3. Troubleshooting61Malfunctions Causes Remedies4. The nozzle or the nozzle holder is not functioning properlyThe engine cannot reach its maximum spe

3. Troubleshooting62R13.4 Troubleshooting by measuring compression pressureCompression pressure drop is one of major causes of increasing blowby gas

3. Troubleshooting63R1(3) Engine speed and compression pressure (for reference)(4) Measured value and troubleshootingWhen the measured compression pr

4. Disassembly and reassembly644. Disassembly and reassembly4.1 Disassembly and reassembly precautions(1) Disassembly• Take sufficient time to accura

4. Disassembly and reassembly654.2 Disassembly and reassembly toolsThe following tools are required when disassembling and reassembling the engine.Pl

4. Disassembly and reassembly66Name of tool Illustration RemarksCopper hammer Local supplyMallet Local supplyNippers Local supplyPliers Local supplyO

4. Disassembly and reassembly67Name of tool Illustration RemarksLead rod Local supplyFile Local supply 1 setRod spanner for hexagon socket head screw

4. Disassembly and reassembly684.2.2 Special hand toolsName of tool Illustration RemarksPiston pin insertion/extraction toolConnecting rod small end

4. Disassembly and reassembly69Name of tool Illustration RemarksLube oil filter case removerPiston ring replacer (for removal / installation of pisto

12.7.1 Oil pressure alarm... 1971

4. Disassembly and reassembly70Name of tool Illustration RemarksPress tool 1 for filler neck-Press tool 2 for filler neck copper tube-Stem seal inser

4. Disassembly and reassembly714.2.3 Measuring instruments(1) Application of toolsName of tool Illustration RemarksVernier calipers 0.05 mm0-150 mmMi

4. Disassembly and reassembly72(2) Use of toolsNo. Name of tool Use Illustration1 Dial gauge Measures shaft bending, distortions of levelness, and ga

4. Disassembly and reassembly73No. Name of tool Use Illustration9 V Block Measures shaft distortion.10 Torque wrench Used to tighten bolts and nuts t

4. Disassembly and reassembly74No. Name of tool Use Illustration16 Rotation gaugeContact type Measures rotation speed by placing at the indentation h

4. Disassembly and reassembly754.2.4 Other materialItems Usual contents Features and applicationLiquid gasket Three BondNo.1TB1101200g(1 kg also avai

4. Disassembly and reassembly76R1[Notice]It is recommended that the liquid gasket of Three Bond TB1212 should be used for service work.Before providi

4. Disassembly and reassembly774.3 Disassembly and reassembly4.3.1 Disassembly• Preparation on a boatFor engines mounted in an engine room of a ship,

4. Disassembly and reassembly78[NOTE: ]If a lube oil supply/discharge pump is used for the engine, the intake hose is placed in the dipstickguide, an

4. Disassembly and reassembly79(5) Removing the intake silencer1) Remove the air intake hose attached to the intakemanifold.2) Remove the intake sile