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GB California Proposition 65 Warning Diesel engine exhaust and some of its constituents are recognized by the State of California to cause cancer, birth defects, and other reproductive harm. MARINE DIESEL ENGINE MODELS: 4JH3-TE/-HTE/-DTE/-TCE Series OPERATION MANUAL JH-Turbo-Engels1a 30-06-2002 13:17 Pagina 1

Yanmar 4JH3 Operation Manual

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Page 1: Yanmar 4JH3 Operation Manual


CaliforniaProposition 65 Warning

Diesel engine exhaust and some of its constituents are recognized by

the State of California to cause cancer, birth defects, and other

reproductive harm.




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Page 2: Yanmar 4JH3 Operation Manual




Your Warranty Rights and Obligations:California:The California Air Resources Board and Yanmar Co., Ltd. ("Yanmar") is pleased to explain the emission control system warranty on your off-road compression-ignition model year 2000 or later engine. In California, new heavy-duty off-road engines must be designed, built and equipped to meet the State's stringent anti-smog standards.

All StatesYanmar warrants that the engine is: (1) designed, built and equipped so as to conform with all applicable emissions regulations, including in California, all applicable regulations adopted by the Air Resources Board; and (2) free from defects in materials and workmanship which cause such engine to fail to conform with applicable emissions regulations for its warranty period.

Yanmar warrants the emission control system on your engine for the periods of time listed be-low provided there has been no abuse, neglect or improper maintenance of your engine. Your emission control system may include parts such as the fuel injection system and the air induc-tion system. Also included may be hoses, belts, connectors and other emission-related as-semblies.

Where a warrantable condition exists, Yanmar will repair your heavy-duty off-road engine at no expense to you for diagnosis, parts or labor. Warranty services or repairs wiII be provided at a Yanmar authorized Dealer.

Manufacturer's Warranty Period:The model year 2000 or later heavy-duty off-road engines are warranted for the periods listed below. If any emission-related part on your engine is defective, the part will be replaced by Yanmar.

Engine Type Warranty Period by Number of Years or Hours of 0peration

Engines rated at or above 19 kW Warranty period is five (5) years or 3,000 hours of use, whichever occurs first. In the absence of a device to measure hours of use, the engine has a warranty period of five (5) years.

Engines rated under 19 kW Warranty period is two (2) years or 1,500 hours of use, whichever occurs first. In the absence of a device to measure hours of use, the engine has a warranty period of two (2) years.

Constant speed engines rated under 37 kW with rated speeds greater than or equal to 3,000 min-1

Warranty period is two (2) years or 1,500 hours of use, whichever occurs first. In the absence of a device to measure hours of use, the engine has a warranty period of five (5) years,

Constant speed engines rated at or above 37 kW

Warranty period is five (5) years or 3,000 hours of use, whichever occurs first. In the absence of a device to measure hours of use, the engine has a warranty period of five (5) years.

Warranty-GB.fm Page 1 Tuesday, February 22, 2005 9:06 PM

Page 3: Yanmar 4JH3 Operation Manual


Warranty Coverage:This warranty is transferable to each subsequent purchaser for the duration of the warranty period. Repair or replacement of any warranted part will be performed at an authorized Yan-mar dealer.

Warranted parts not scheduled for replacement as required maintenance in the owner's man-ual shall be warranted for the warranty period. Any part repaired or replaced under warranty shall be warranted for the remaining warranty period. Warranted parts scheduled for replace-ment as required maintenance in the owner's manual are warranted for the period of time prior to the first scheduled replacement.

Yanmar is liable for damages to other engine components caused by the failure of any war-ranted part during the warranty period.

Any replacement part which is functionally identical to the original equipment part in all re-spects may be used in the maintenance or repair of your engine, and shall not reduce Yan-mar's warranty obligations. Add-on or modified parts that are not exempted may not be used. The use of any non-exempted add-on or modified parts shall be grounds for disallowing a war-ranty.

Warranted Systems/ Parts Covered by this Warranty:(1) Fuel Injection System(2) Cold start enrichment system(3) Intake manifold(4) Turbocharger Systems(5) Exhaust manifold

Exclusions:Failures other than those arising from defects in material or workmanship are not covered by this warranty. The Warranty does not extend to the following: malfunctions caused by abuse, misuse, improper adjustment, modification, alteration, tampering, disconnection, improper or inadequate maintenance, or use of non-recommended fuels or lubricating oils; accident-caused damage, or replacement of expendable items made in connection with scheduled maintenance. Yanmar disclaims any responsibility for incidental or consequential damages such as loss of time, inconvenience, loss of use of equipment/engine or commercial loss.

Owner's Warranty Responsibilities:As the heavy-duty off-road engine owner, you are responsible for the performance of the required maintenance listed in your owner's manual. Yanmar recommends that you retain all documentation, including receipts, covering mainte-nance on your heavy-duty off-road engine, but Yanmar cannot deny warranty solely for the lack of receipts, or for your failure to ensure the performance of all scheduled maintenance.

Your engine is designed to operate on diesel fuel only. Use of any other fuel may result in your engine no longer operating in compliance with applicable emissions requirements.

You are responsible for initiating the warranty process. You must present your off-road engine to a Yanmar Dealer as soon as a problem exists. The warranty repairs should be completed by the Dealer as expeditiously as possible. If you have any questions regarding your warranty rights and responsibilities, or would like information on the nearest Yanmar Dealer/authorized service center, you should contact Yanmar Marine U.S.A. Corp. at Adairsville, GA U.S.A.

Warranty-GB.fm Page 2 Tuesday, February 22, 2005 9:06 PM

Page 4: Yanmar 4JH3 Operation Manual





INTRODUCTION .............................................. 3

1 FOR YOUR SAFETY ................................... 41.1 Warning symbols ................................ 41.2 Safety Precautions.............................. 41.3 Warning Labels ................................... 7

2 PRODUCT EXPLANATION ......................... 82.1 Use, Driving System etc...................... 82.2 Engine Specifications ....................... 102.3 Names of Parts ..................................132.4 Major Servicing Parts.........................142.5 Control Equipment ............................15

2.5.1 Control Panel...........................152.5.2 Remote Control Handle...........182.5.3 Stopping Equipment ...............19

3 OPERATION ............................................. 203.1 Fuel Oil, Lube Oil & Cooling Water .... 20

3.1.1 Fuel Oil.................................... 203.1.2 Lube Oil .................................. 203.1.3 Cooling Water......................... 21

3.2 Before Initial Operation ..................... 223.2.1 Supply Fuel Oil........................ 223.2.2 Bleeding the fuel system......... 223.2.3 Supply Engine Lube Oil........... 223.2.4 Supply Clutch Lube Oil .......... 233.2.5 Supply Cooling Water............. 233.2.6 Cranking (Idling)...................... 243.2.7 Check and Resupply Lube

Oil and Cooling Water ............. 25

3.3 Operating your Engine ...................... 253.3.1 Inspection Before Starting ...... 253.3.2 How to Start the Engine .......... 273.3.3 Operation................................ 283.3.4 Cautions during Operation...... 293.3.5 Stopping the Engine ............... 303.3.6 Procedure............................... 31

3.4 Long term Storage ............................ 32

4 MAINTENANCE & INSPECTION............... 344.1 General Inspection Rules .................. 344.2 List of Periodic Inspection Items ....... 354.3 Periodic Inspection Items ................. 37

4.3.1 Inspection on Initial 50 Hrs. ofOperation (or after 1 month) .... 37

4.3.2 Inspection Every 50 Hours (or monthly)............................. 38

4.3.3 Inspection Every 250 Hrs ........ 394.3.4 Inspection Every 500 Hrs ........ 424.3.5 Inspection Every 1000 Hrs ...... 42

5 TROUBLE AND TROUBLESHOOTING..... 435.1 Trouble and Troubleshooting............ 435.2 Emergency Repairs for Clutch .......... 44

6 PIPING DIAGRAMS .................................. 47

7 WIRING DIAGRAMS ................................. 48

APPENDIX A (Piping diagrams)..................... A-1(See the back of this Manual)

APPENDIX B (Wiring diagrams) .................... B-1 (See the back of this Manual)

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Page 5: Yanmar 4JH3 Operation Manual


This Operation Manual describes the operation, maintenance and inspection of the 4JH3-TE/-HTE/-DTE/-TCE Series Yanmar Marine Diesel Engines.

Read this Operation Manual carefully before operating the engine to ensure that it is usedcorrectly and that it stays in the best possible condition.

Keep this Operation Manual in a convenient place for easy access.

If this Operation Manual is lost or damaged, order a new one from your dealer or distributor.

Make sure this manual is transfered to subsequent owners. It should be considered as apermanent part of the engine and remain so.

Constant efforts are made to improve the quality and performance of Yanmar products, sosome details included in this Operation Manual may differ slightly from your engine. If youhave any questions about this, please contact your Yanmar dealer or distributor.



Thank you for purchasing a YANMAR Marine Diesel Engine.

Operation Manual(Marine Engine)


Code. No.



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Page 6: Yanmar 4JH3 Operation Manual



1. For your safety


Most operation, maintenance and inspection problems arise due to users’ failure to complywith the rules and precautions for safe operation described in this operation manual. Often,users do not understand or recognize the signs of approaching problems. Improperhandling can cause burns and other injuries and can result in death.

Be sure to read this operation manual carefully before operating the engine and observe allof the instructions and precautions described in this manual.

Below follow the warning signs used in this manual and on the products. Pay specialattention to parts containing these words and signs.

DANGER indicates an imminently hazardoussituation which, if not avoided, WILL result in deathor serious injury.

WARNING indicates a potentially hazardous situa-tion which, if not avoided, COULD result in death orserious injury.

CAUTION indicates a potentially hazardous situationwhich, if not avoided, MAY result in minor ormoderate injury.This sign is also be used to alert against unsafe practices.

The descriptions captioned by are particularly important cautions forhandling. If you ignore them, the performance of your machine may deteriorate leading toproblems.


(Observe these instructions for your own safety!)

Precautions for Operation

Filler Cap of Fresh Water TankNever open the cap of the fresh water tank while the engine is still hot.Steam and hot water will spurt out and burn you seriously. Wait until thetemperature of the fresh water tank has dropped, wrap a cloth aroundthe filler cap and loosen the cap slowly. After inspection, refasten thecap firmly.






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Page 7: Yanmar 4JH3 Operation Manual

1. For your safety

BatteryNever smoke or permit sparks near the battery, because it may emitexplosive hydrogen gas. Place the battery in a well-ventilated place.

FuelUse only diesel oil. Never use other fuels, including gasoline, kerosene,etc., because they could cause a fire. The wrong fuel could also causethe fuel injection pump and injector to fail due to lack of properlubrication. Be sure to check that you have selected the correct dieselfuel before filling the fuel tank.

Fire PreventionBe sure to stop the engine and confirm that there are no open flames inthe vicinity before supplying fuel. If you do spill fuel, wipe such spillagecarefully and dispose of the wiping materials properly. Wash your handsthorougly with soap and water. Never place oil or other flammable material in the engine room.Install a fire extinguisher near the engine room, and familiarize yourselfwith its use.

Exhaust GasExhaust gas contains poisonous carbon monoxide and should not beinhaled.Be sure to install ventilation ports or ventilators in the engine room andensure good ventilation during engine operation.

Moving PartsDo not touch or let your clothing get caught in the moving parts of theengine, such as the front drive shaft, V-belt or propeller shaft, duringengine operation. You will be injured.Never operate the engine without the covers on the moving parts.Before starting the engine, check to see that any tools or cloths used inmaintenance have been removed from the area.

BurnsThe whole engine is hot during operation and immediately afterstopping. The turbocharger, intercooler, exhaust manifold, exhaust pipeand high pressure fuel pipe are very hot. Never touch these parts withyour body or clothing.









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Page 8: Yanmar 4JH3 Operation Manual

1. For your safety



Alcohol Never operate the engine while you are under the influence of alcohol.Never operate the engine when you are ill or feeling unwell.


Battery FluidBattery fluid is dilute sulfuric acid. It can blind you if it gets in your eyes,or burn your skin. Keep the fluid away from your body. If you touch it,wash it off immediately with a large quantity or fresh water and call yourdoctor for treatment.

Fire by Electric Short-CircuitsAlways turn off the battery switch before inspecting the electricalsystem.Failure to do so could cause short-circuiting and fires.

Stop the engine before servicingStop the engine before you service it.Turn the battery switch off. If you must inspect while the engine is inoperation, never touch moving parts. Keep your body and clothing wellclear of all moving parts.

ScaldsIf extracting oil from the engine while it is still hot, don’t let the oil splashon you. Wait until the temperature has dropped before extracting cooling waterfrom the engine. Don’t let it splash on you.

Forbidden ModificationsNever release the limiting devices such as the engine speed limit, fuelinjection limit, etc.Modification will impair the safety and performance of the product andshorten product life.Also note that any troubles arising from modification are not covered byour warranty.

Precautions for Treating WasteNever dispose of waste oil or other fluid in a field, sewer, river, or the sea.Treat waste matters safely observing regulations or laws. Ask a waste recovery company to collect it.








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Page 9: Yanmar 4JH3 Operation Manual



To insure safe operation, warning devicelabels have been attached. Their location isshown below and they should always bevisible. Please replace if damaged or lost.

1. For your safety



Product Safety Labels, Parts Code Numbers

� 128377-07350� 128296-07260� 128296-07300� 196630-12980

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Page 10: Yanmar 4JH3 Operation Manual


This is a light, compact diesel engine for use in pleasure boats. The engine is equipped witha turbocharger and intercooler which insures maximum output while preserving lightnessand compact size. (The 4JH3-TE series is equipped with the turbocharger only.)

Power output for this group of engines increases progressively from 4JH3-TE, 4JH3-HTE to4JH3-DTE.

The inboard series is equipped with a marine gear connecting the output shaft with thepropeller shaft for operation.The different types of marine gears used for each series are shown below.

In order to obtain full performance from your engine, it is imperative that you check the sizeand structure of the hull and use a propeller of the appropriate size.

The engine must be installed correctly with safe cooling water and exhaust piping andelectrical wiring. The PTO work should be easy to use for onboard equipment.

The laws of some countries may require hull and engine inspections, depending on the use,size and cruising area of the boat.

The installation, fitting and surveying of this engine all require specialized knowledge andengineering skills. Consult Yanmar’s local subsidiary in your region or your distributor ordealer.

Consult your Yanmar dealer or distributor when selecting optional parts. Optional partsselections should take into account operational and surrounding conditions.

This Operation Manual explains the basic points for standard operation. Variations areexplained under the specially marked sections.

2. Product explanation



4JH3-TE 4JH3-HTE 4JH3-DTEMarine Gear Series Series Series

KBW21 Clutch 4JH3-TE 4JH3-HTE N/A

KM4A Clutch 4JH3-TBE 4JH3-HTBE N/A


Mechanical wet cone clutchInput/output special parallel drive

Mechanical wet cone clutch7° Down angle drive

Hydraulic wet multiple disk clutch8° Down angle drive

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Page 11: Yanmar 4JH3 Operation Manual

This Operation Manual explains the basic points for standard operation. Variations areexplained under the letter emblems for easy reference.

Model : Explanation of indicated model only.

Option : Explanation of optional parts.

Customer : Explanation of use of parts from other boat manufacturers.

In sections without letter emblems, the explanation applies to all models.

Explanation for driving devices, propellers, etc. and optional parts are not included,and special attention should be paid to the explanations and safety precautions in theoperation manuals provided by the boat and equipment manufacturers.

2. Product explanation



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Page 12: Yanmar 4JH3 Operation Manual

2.2 Engine Specifications2.2.1

2. Product explanation



Item Unit Model

Engine Model -- 4JH3-TE 4JH3-TBE 4JH3-THE 4JH3-TCE

Type --

Combustion system --

Number of cylinders -- 4

Bore x stroke mm 84 x 90

Displacement � 1.995

Aspiration system -- turbocharger

Continuous Output/crankshaft kW/rpm 50.7 / 3700rating output speed (hp/rpm) (69 / 3700)

One hour Output/crankshaft kW/rpm 55.2 / 3800rating output speed (hp/rpm) (75 / 3800)

Low idling rpm 700 ± 25

Fuel injection timing (b.T.D.C.) º 12 ± 1

Fuel injection pressure kg/cm2 220 ± 5

Main power take off

Front power take off

Direction of Crankshaftrotation Propeller shaft (ahead)

Cooling system

Lubrication system

TypeStarting Starting motorsystem

AC generator

EngineLubricating oil standard 6.3 7.05capacity (rake angle) unit � (7°) (0°)

Model KWB21 KM4A KMH4A SD40-4TSail Drive


Marine gear

Reduction ratioForward 2.17 2.62 1.47 2.14 2.63 3.30 2.04 2.45 2.32

Reverse 3.06 3.06 1.47 2.14 2.63 3.30 2.04 2.45 2.32

Lubricating oilcapacity

Total � 1.2 1.3 2.0 1.8

Dimensions L x W x H mm 906 x 560 x 635 888 x 565 x 635 938 x 565 x 635 1086 x 565 x 433

Cooling water Fresh water tank � 6.0capacity Subtank � 0.8

Engine weight with marine gear kg 249 247 250 260

vertical 4-cycle water cooled diesel engine

direct injection

at flywheel side

at crankshaft V-pulley side

Counter-clockwise viewed from stern

fresh water cooler with heat exchanger

complete enclosed forced lubrication


DC 12V, 1.4 kW

12V, 55A (12V, 80A optional)

clockwise bi-rotation

mechanical wet multiple disk clutchInput/output eccen-

tric parallel drive

mechanical wetcone clutch 7°

down angle drive

hydraulic wetmultiple disk clutch8° down angle drive

Cone clutch

1.) Rating condition: ISO 3046-1 and ISO 8665 2.) 1hp=0.7355 kW

counter-clockwise orclockwise viewed from


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Page 13: Yanmar 4JH3 Operation Manual

2. Product explanation




Item Unit Model

Engine Model -- 4JH3-HTE 4JH3-HTBE 4JH3-HTHE

Type --

Combustion system --

Number of cylinders -- 4

Bore x stroke mm 84 x 90

Displacement � 1.995

Aspiration system -- turbocharger, intercooler

Continuous Output/crankshaft kW/rpm 67.7 / 3700rating output speed (hp/rpm) (92 / 3700)

One hour Output/crankshaft kW/rpm 73.6 / 3800rating output speed (hp/rpm) (100 / 3800)

Low idling rpm 700 ± 25

Fuel injection timing (b.T.D.C.) º 12 ± 1

Fuel injection pressure kg/cm2 220 ± 5

Main power take off

Front power take off

Direction of Crankshaftrotation Propeller shaft (ahead)

Cooling system

Lubrication system

TypeStarting Starting motorsystem

AC generator

EngineLubricating oil standard 6.3 7.5capacity (rake angle) unit � (7°) (0°)

Model KWB21 KM4A KMH4A


Marine gear

Reduction ratioForward 2.17 2.62 1.47 2.14 2.63 3.30 2.04 2.45

Reverse 3.06 3.06 1.47 2.14 2.63 3.30 2.04 2.45

Lubricating oilcapacity Total � 1.2 1.3 2.0

Dimensions L x W x H mm 906 x 576 x 660 888 x 581 x 660 938 x 581 x 660

Cooling water Fresh water tank � 7.2capacity Subtank � 0.8

Engine weight with marine gear kg 258 256 259

vertical 4-cycle water cooled diesel engine

direct injection

at flywheel side

at crankshaft V-pulley side

Counter-clockwise viewed from stern

fresh water cooler with heat exchanger

complete enclosed forced lubrication


DC 12V, 1.4 kW

12V, 55A (12V, 80A optional)

clockwise bi-rotation

mechanical wet multipledisk clutch Input/outputeccentric parallel drive

mechanical wet coneclutch 7° down angle


hydraulic wet multipledisk clutch 8° down

angle drive

1.) Rating condition: ISO 3046-1 and ISO 8665 2.) 1hp=0.7355 kW

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Page 14: Yanmar 4JH3 Operation Manual

2. Product explanation




Item Unit Model

Engine Model -- 4JH3-DTHE

Type --

Combustion system --

Number of cylinders -- 4

Bore x stroke mm 84 x 90

Displacement � 1.995

Aspiration system -- turbocharger, intercooler

Continuous Output/crankshaft kW/rpm 85.3 / 3700rating output speed (hp/rpm) (116.0 / 3700)

One hour Output/crankshaft kW/rpm 91.9 / 3800rating output speed (hp/rpm) (125 / 3800)

Low idling rpm 700 ± 25

Fuel injection timing (b.T.D.C.) º 12 ± 1

Fuel injection pressure kg/cm2 220 ± 5

Main power take off

Front power take off

Direction of Crankshaftrotation Propeller shaft (ahead)

Cooling system

Lubrication system

TypeStarting Starting motorsystem

AC generator

EngineLubricating oil standard 7.5capacity (rake angle) unit � (0°)

Model KMH4A


Marine gearReduction ratio

Forward 2.04 2.45

Reverse 2.04 2.45

Lubricating oilcapacity

Total � 2.0

Dimensions L x W x H mm 938 x 581 x 660

Cooling water Fresh water tank � 7.2capacity Subtank � 0.8

Engine weight with marine gear kg 260

vertical 4-cycle water cooled diesel engine

direct injection

at flywheel side

at crankshaft V-pulley side

clockwise viewed from stern

fresh water cooler with heat exchanger

complete enclosed forced lubrication


DC 12V, 1.4 kW

12V, 55A (12V, 80A optional)


hydraulic wet multiple disk clutch 8° down angle drive

1.) Rating condition: ISO 3046-1 and ISO 8665 2.) 1hp=0.7355 kW

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Page 15: Yanmar 4JH3 Operation Manual

2. Product explanation



Non Operation Side

2.3 Names of Parts Operation Side Oil cooler (engine)

Fuel oil filter

Name plate Fuel priming pump

Fresh waterpump

Trawling lever(option)

Dipstick (clutch) Dipstick


Lube oil filter

Fuel injection pump

Intake airsilencer

Filler cap Fresh water coolerAlternator

* Intercooler Turbocharger


Clutch leverSeawater pump Starter Oil cooler(clutch)

NOTE: The 4JH3-DTHE engine (with KMH4A clutch) is used as the example for the above diagram.The 4JH3-TE Series is not equipped with an intercooler (indicated by * in the diagram).

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Page 16: Yanmar 4JH3 Operation Manual

2. Product explanation



Name of part Function

Fuel filter Removes dust and water from fuel. The internal element (filter) should bechanged periodically. A water separator is on the bottom of the filter and should be drainedperiodically.

Fuel priming pump This is a manual fuel pump. Moving the knob on the top of the fuel filterfeeds the fuel. The pump is also used to bleed air from the fuel system.

Fuel feed pump This is a mechanical pump used to feed fuel to the fuel injection pump. It isbuilt into the fuel injection pump.

Filler port (engine) Filler port for engine lube oil.

Filler port (marine gear) Filler port for marine gear lube oil.

Dipstick (Lube oil) Gauge stick for determinining the level of the engine and marine gear oil.

Lube oil filter Filters fine metal fragments and carbon from the lube oil.Filtered lube oil is distributed to the engine’s moving parts.

Cooling System Seawater passes through the heat exchanger cooling the fresh water,which in turn cools the engine.

Fresh water cooling

Fresh water pump There are two cooling systems: fresh water and seawater.The fresh water pump is run by the alternator and the V-belt.

Fresh water cooling The fresh water in the fresh water cooler is fed to the engine by the freshwater pump. The cooling fresh water returns to the engine after it is cooledwith seawater in the fresh water cooler.

Filler cap The filler cap on the cooling water tank covers the water supply port. Thecap has a pressure regulating valve. When the cooling water temp. rises,the pressure rises inside the fresh water cooler.

Subtank The pressure regulating valve releases vapor and hot water overflow to thesubtank.

Oil cooler (engine oil) This heat exchanger cools high temp. engine oil with seawater.

Oil cooler (clutch oil) This heat exchanger cools high temp. clutch oil with seawater.

Turbocharger With the pressurized intake air feeding device the exhaust gas turbine isrotated by exhaust gas, and the power is used to rotate the blower.This pressurizes the intake air for sending to the cylinder gives high poweroutput.

Intercooler This heat exchanger cools the pressurized intake air from theturbocharger with seawater and further compresses it.

Intake air silencer This is the air intake silencer. The silencer guards against dirt in the air andreduces the noise of air intake.

Name plate Name plates are provided on the engine and the marine gear and have themodel, serial number and other data.

Starter Starter motor for the engine. Powered by the battery.

Alternator Rotates by belt drive, generates electricity and charges the battery.

2.4 Major Servicing Parts

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Page 17: Yanmar 4JH3 Operation Manual

2.5 Control Equipment2.5.1 Control Panel

The instrument panel is located in the control room. The following instruments enable you tostart/stop the engine and to monitor its condition during operation.

B type New B type

C type New C type

D type New D type



2. Product explanation

� �

� �

� �


� Tachometre� Hour metre� C.W. temp. metre � L.O. temp. metre� Boost pressure metre

Alarm lamps� Starter switch� Stop button switch � Buzzer stop switch � Alarm buzzer

Illumination switch Digital clock� Fuse

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Page 18: Yanmar 4JH3 Operation Manual

(1) Metres The following metres are located in theupper centre part of the instrument panel.• B/C/D and New B/C/D type panels use

analog electric systems and have apointer indicator.

Turn the panel light switch ON for easyviewing.• Tachometre

The engine's rotation speed is indicated. Load and engine rotation can bemonitored.

• Hour metreThe number of hours of operation isindicated, and can be used as a guide forperiodic maintenance checks.

• Cooling Water Temperature MetreOption Instrument Panel C.D.The cooling water temperature isindicated. Enables monitoring of thecooling condition of the engine.

• Lube Oil Pressure MetreOption Instrument Panel C.D.The engine oil pressure is indicated.Enables monitoring of the condition ofthe engine's lube oil.

1 BATTERY CHARGE When the charge is abnormal, thelamp will come on. When chargingbegins the lamp will go off. (Alarm

buzzer will not sound when the lamp comeson.)

2 C. WATER TEMP When the temperature of thecooling fresh water exceeds themaximum (95°C or higher), the lamp

will light. Continuing operation attemperatures exceeding the maximum willresult in damage and seizure. Check theload and the fresh water cooling system forany abnormalities.

3 LUB. OIL PRESS.When the lube oil pressure fallsbelow normal the oil pressuresensor will register this and the lamp

will come on. Continuing operation with

2. Product explanation



insufficient oil will result in damage andseizure. Check the oil level.

4 FUEL FILTERWhen the drain inside the waterseparator in the fuel filter becomesexcessive, the sensor will cause the

lamp to come on. Clean out the drain in thewater separator. If operation is continuedwithout cleaning, it will become impossibleto feed fuel to the engine or damage andseizure of the fuel injection pump will result.

5 EXHAUST Option When the amount of coolingseawater being dischargedbecomes too small, the sensor will

activate the lamp. Continuing operationunder this condition will result in damageand seizure. Check for clogging in theseawater cooling system and damagedparts.

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Page 19: Yanmar 4JH3 Operation Manual

2. Product explanation



(2) Controls and Equipment

Key Switch Rotary switch with 4 positions.In the OFF position, the switch key can be inserted or removed.In OFF, all electric current is cut off.In ON (1 position to the right), the engine is turned on. In ON, electric current to the controls and equipment is turnedon.In the START position the engine will start.The engine cannot be stopped with the key switch.In GLOW, position for turning on the air heater. The air heater Option aids starting during cold conditions bywarming up the intake air before starting.

Note: Neutral Safety Switch The engine can only be started when the clutch is in neutral. If anattempt is made to start the engine in any other position, theneutral safety switch will operate to make starting impossible.



(3) Alarm Equipment (lamps and buzzer)MechanismWhen the sensor detects a problem duringoperation, the lamps come on and thebuzzer goes off.

Alarm monitors are located on the controlpanel. Under normal conditions, the moni-tors are off. When there is a problem, themonitors light up.

(4) Alarm DevicesCheck that the pilot lamps on theinstrument panel are as shown below whenthe starter key is turned on:

NOTE:All these signals will continue until the en-gine starts up or the key is turned off.

Low L.O. pressure alarm lamp LitPilot

Charge lamp Litlamps

Cooling water temp. alarm lamp Off

Controls and Equipment Mechanism

OptionKM4A ClutchKMH4A Clutch

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(2) Trawling Handle Option KMH4A Clutch(The trawling valve is optional to KMH4AClutch only.)The trawling control is a single remotecontrol handle.The marine gear trawling lever operates byremote control cable.The operation labels on the handle are :H : High speed (normal operation) L : Low speed (trawling operation)

Only operate with the trawling handle in thelow speed position, 1000 rpm or less.In L(low speed) the clutch is at half clutchingposition and the propeller turns very slowlyrubbing against the friction plate.The engine cannot be run at high speedunder these conditions.

1. Loosen the handle grip by turning it to theleft.

2. Move the handle toward L and position atthe desired speed.

2. Product explanation



2.5.2 Remote Control Handle

(1) Morse Type Option This remote control system uses a singlehandle to operate marinegear-clutch-(neutral, forward, reverse) and to control theengine speed.

NEUTRAL: Power to the propeller shaft iscut off and the engine idles.FWD (FORWARD)REV (REVERSE)

The handle controls the course of the boat(ahead or astern) and, at the same time,acts as an accelerator increasing the enginespeed as it is pushed further in the FWD orREV direction. If the handle is pulled out,engine speed can be controlled withoutengaging the clutch (clutch remains in theNEUTRAL, no load position).

Yanmar recommends the use of asingle-lever type for the remote con-trol lever. If only the two-lever type isavailable in the market, operate theengine at 1000 rpm or lower beforeengaging and disengaging the marinegear-clutch.


� FWD (forward)� REV (reverse)� NEUTRAL (boat is stopped)� Clutch is disengaged� Pull out handle

� H (High speed) � L (Low Speed)


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2.5.3 Stopping Equipment

Electric Operation

Push the stop button on the instrumentpanel. Continue to push the stop buttonuntil the engine has come to a completestop.

If the engine is stopped suddenly at ahigh temperature, the temperature ofvarious parts will increase and enginetrouble may occur.

2. Product explanation



Before returning to normal high speedoperation, be sure to position thehandle in H.



Stop button on the instrument panel

Engine stopping by stop button

KMH4A Clutch

� Trawling lever� High speed

� Low speed (trawling)

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(3) Fuel SystemInstall the fuel pipe from the fuel tank tothe fuel pump in accordance with thediagram.

3.1.2 Lube Oil

Using other than the specifiedlube oil will lead to seizure ofparts, abnormal wear, and shortenengine life.

(1) Selection of Engine Lube OilUse the following lube oil:• API Classification...............................CD• SAE Viscosity ..............................15W40

(2) Clutch Oil SelectionUse the following lube oil:• 4JH3-TE, 4JH3-HTE Series Converter

oil for automobiles ATF-AKBW21 Clutch

• 4JH3-TBE, 4JH3-HTBE, 4JH3-DTBESeries and 4JH3-THE, 4JH3-HTHE,4JH3-DTHE SeriesKM4A Clutch KMH4A ClutchAPI Classification............... CC or higher SAE Viscosity........................ #20 or #30

3.1 Fuel Oil, Lube Oil, and Cooling Water

3.1.1 Fuel Oil

When other than the specified fueloil is used, the engine will notperform to full capacity and partsmay be damaged.

(1) Selection of Fuel OilUse diesel fuels only.Cetane fuel number should be 45 orgreater.

(2) Handling of Fuel Oil1) Water and dust in the fuel cause engine

failure. When fuel is stored, be sure thatthe inside of the storage container isclean, and that the fuel is stored awayfrom dirt or rain water.

2) Keep the fuel container stationery forseveral hours to allow any dirt or waterto settle to the bottom. Use a pump toextract the clear, filtered fuel from thetop of the container for use.



Use the clear filtered fuel from the upper middle section of the container only, leaving anycontaminated fuel at the bottom.

� Fuel filter� Approx. 20~30 mm Within 500 mm� Drain cock� Fuel cock

� Fuel return� To fuel injection

pump� Fuel tank

Fuel system

3. Operation




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3. Operation

(3) Handling the Lube Oil1) When handling and storing lube oil, be

careful not to allow dust and water toenter the lube oil. Clean around thefilter port before refilling.

2) Do not mix lube oils of different typesor brands. Mixing may cause thechemical characteristics of the lube oilto change and lubricating performanceto drop, reducing the engine’s life. Before supplying lube oil to the engineand marine gear for the first time,extract all the lube oil already in thetank. Use new lube oil.

3) Lube oil supplied to the engine willundergo natural degeneration with timeeven when the engine is not used.Lube oil should be replaced at thespecified intervals, regardless ofwhether the engine is being used ornot.

3.1.3 Cooling Water

It is important to check the cooling waterdaily. Be sure to use clean soft water (tapwater) for cooling fresh water.

Be sure to add antirust or antifreezeto cooling fresh water. In cold seasons, the antifreeze isespecially important. Without antirust, cooling performancewill drop due to scale and rust in thecooling water system. Withoutantifreeze, cooling water will freezeand expand, breaking various parts.For your reference, antifreeze mixedwith antirust is now available in themarket.

Handling of Cooling Water1. Choose antirust which will not have any

adverse effects on the materials (castiron, aluminum, copper, etc.) of theengine’s fresh water cooling system.

2. Use the proper mixing ratio of antirustto fresh water strictly as instructed bythe antirust maker.

3. Replace the cooling water periodically,according to the maintenance schedulegiven in this operation manual.

4. Remove the scale from the coolingwater system periodically, according tothe instructions in this operationmanual.

5. Use the proper mixing ratio ofantifreeze to fresh water strictly, asinstructed by the antifreeze maker. Iftoo much antifreeze is used, the coolingperformance of the cooling water willdrop and the engine may becomeoverheated.

6. Do not mix different brands of antirustor antifreeze. Chemical reactions may make theantifreeze or antirust useless andengine trouble could result.

Excessive use of antifreeze alsolowers the cooling efficiency ofthe engine. Be sure to use themixing ratios specified by theantifreeze maker for your temper-ature range.


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3.2 Before Initial Operation

Perform the following before using theengine for the first time:

3.2.1 Supply Fuel Oil

Using gasoline, etc. maycause a fire.To avoid mistakes, besure to double-check thekind of fuel before insert-ing. Wipe off any spilledfuel carefully.

1. Before filling with fuel, wash out the fueltank and fuel system with cleankerosene or light oil.

2. Fill the tank with clean fuel oil free of dirtand water.

3.2.2 Bleeding the Fuel System

Bleed the fuel system according to thefollowing procedure. When there is air inthe fuel system, the fuel injection pump willnot be able to function.

1. Open the fuel cock of the fuel tank.2. Loosen the air bleeding bolt on the top

of the fuel filter by turning it 2~3 times.


3. Operation

3. Move the priming pump knob up anddown until fuel mixed with air bubblesflows out of the air bleeding bolt andtighten the air bleeding bolt. The primingpump is on the top of the fuel filter.

3.2.3 Supply Engine Lube Oil

1. Remove the filler port cap (yellow) at thetop of the bonnet, and fill with engineoil.

2. Fill with oil to the upper limit on thedipstick. Insert the dipstick fully tocheck the level.Engine oil capacity: See 2.2 EngineSpecifications

3. Tighten the filler port cap securely byhand.

Do not overfill.Overfilling will cause oil to be sprayedout from breather and lead to engineproblems.

� Priming pump � Air bleeding bolt



� Filler port� Bonnet

Dipstick� Upper limit

� Lower limit

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3.2.5 Supply Cooling Water

Supply cooling water according to thefollowing procedures. Be sure to addantirust or antifreeze to the cooling water.

1. Be sure to close the water drain cocks.

Note: The water drain cocks are openedbefore shipping from the plant.

2. Remove the filler cap of the fresh watercooler by turning the cap counterclock-wise 1/3 of a turn.



3. Operation

3.2.4 Supply Clutch Lube Oil

1. Remove the filler port cap at the top ofthe bonnet, and fill with marine gear-clutch- lube oil.

2. Fill with oil to the upper limit on thedipstick. Insert the dipstick fully tocheck the level.Clutch oil capacity: See 2.2 EngineSpecifications

3. Tighten the filler port cap securely byhand.

Do not overfill.Overfilling will cause oil to be sprayedout during operation and affect theefficiency of the marine gear.


KMH4A Clutch4JH3-TE series

� Oil filler port cap� Upper limit/Lower limit


� Fresh water � Seawater

� Filler cap � Fresh water cooler Dents � Notches



� ��

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3.2.6 Cranking

When the engine is being used for the firsttime or has not been used for a longperiod of time, lube oil will not bedistributed to all of the operating parts.Using the engine in this condition will leadto seizure.After a long period of disuse, distributelube oil to each part by cranking. Performin accordance with the following pro-cedures before beginning operation.

1. Open Kingston cock.2. Open fuel tank cock.3. Put remote control lever in NEUTRAL.

4. Turn on battery switch and insert keyinto key switch. Turn the key to the ONposition.

5. Electric stop devicePush the stop button on the instrumentpanel continuously while cranking.

6. When the key switch is turned, theengine will begin cranking. Continuecranking for about 5 seconds, andcheck for abnormal noise during thattime. (If you remove your hand from thestop knob or stop button while cranking,the engine will start.)



� To fresh water cooler � Upper limit Lower limit � Cap

� Forward � Neutral Reverse


3. Operation

3. Pour cooling water slowly into the freshwater tank so that air bubbles do notdevelop. Supply until the water over-flows from the filler port.Fresh water tank capacity: See 2.2Engine Specifications

4. After supplying cooling water, replacefiller cap and tighten it firmly. Failure todo so will cause water leakage. To re-place the cap, align the detents on thebottom of the cap with the notches onthe filler port and turn clockwise 1/3 of aturn.

5. Remove the subtank cap and fill withwater to the lower limit.Replace cap.Subtank capacity: 0.8 �

6. Check the rubber hose connecting thesubtank to the fresh water cooler. Besure the hose is securely connected andthere is no looseness or damage. Whenthe hose is not watertight, an excessiveamount of cooling water will be used.

If the filler cap isloose, hot steam andwater will spout outwhich may causeburns.


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(1) Visual ChecksCheck for the following:1. Lube oil leakage from the engine2. Fuel oil leakage from the fuel system 3. Water leakage from the cooling water

system 4. Damage to parts5. Loosening or loss of bolts

If any problem is found, do not operate theengine before completing repairs.

(2) Checking and Resupplying Fuel OilCheck the fuel level inside the fuel tankand supply with the recommended fuel, ifnecessary. (See 3.2.1)

(3) Checking and Resupplying EngineLube Oil

1. Check the engine oil level with the oildipstick.

2. If the oil level is low, supply with therecommended lube oil using the fillerport. Supply oil up to the top mark onthe oil dipstick. (See 3.2.3)

(4) Checking and Resupplying ClutchLube Oil

1. Check the clutch oil level with the oildipstick.

2. If the oil level is low, supply with therecommended lube oil using the fillerport. Supply oil up to the top mark onthe oil dipstick. (See 3.2.4)

(5) Checking and Resupplying FreshWater (For Fresh Water CoolingSystem)

Check the fresh water level beforeoperation while the engine is cold.Checking the water level while the engineis hot is dangerous, and the cooling waterreading will be misleading due to thermalexpansion. Check and supply cooling water routinelyat the subtank only.Do not remove the filler cap of the freshwater tank during usual operation.



3. Operation

3.2.7 Check and Resupply Lube Oil andCooling Water

When engine oil, clutch oil, or coolingwater is supplied for the first time or whenthey must be replaced, conduct a trialoperation of the engine for about 5minutes and check the quantity of lube oiland cooling water. The trial engine oper-ation will send the lube oil and coolingwater to the parts, so the lube oil andcooling water levels will drop. Check andresupply as necessary.1. Supplying engine lube oil (See 3.2.3)2. Supplying marine gear lube oil

(See 3.2.4)3. Supplying cooling water (See 3.2.5)

3.3 Operating your engine


Exhaust gas

Moving parts


3.3.1 Inspection Before Starting

Before starting the engine, make it a dailyrule to conduct the following inspections:


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3. Operation

1. Check that the cooling fresh water levelis above the lower limit on the side ofthe subtank.

2. If the water level is close to the lowerlimit, remove the subtank cap andsupply fresh water.

3. When the water in the subtank runs out,remove the filler cap of the fresh watercooler and supply water until it over-flows from the filler port. (See 3.2.5)

If the cooling fresh water runs out toooften, or only the cooling fresh waterin the fresh water tank drops withoutany change in the water level of thesubtank, there may be some leakageof water or air. In such cases, consultyour Yanmar dealer or distributorwithout delay.

Note: The water rises in the subtank duringengine operation.This is not abnormal. After stopping theengine, the cooling water cools downand the extra water in the subtankreturns to the fresh water tank.

If the filler cap isloose, hot steam andwater will spout outwhich may causeburns.

DANGER(6) Checking the Remote Control HandleBe sure to check that the remote controlhandle lever moves smoothly before use. Ifit is hard to operate, lubricate the joints ofthe remote control cable and also the leverbearings.If the lever comes out or there is play in thelever, adjust the remote control cable.(See 4.3.4 (5))

(7) Preparing Fuel, Lube Oil, and CoolingFresh Water in Reserve

Prepare sufficient fuel for the day’soperation. Always store lube oil andcooling fresh water in reserve (for at leastone refill) onboard, to be ready for emer-gencies.

(8) Checking the Alarm Devices ElectricOperation

When operating the key switch, check thatthe alarm devices work normally. (See2.5.1 (4))


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3. Operation

3.3.2 How to Start the Engine

(1) Start the engine according to thefollowing procedures:

Electric Operation1. Open the Kingston cock.2. Open the fuel tank cock.3. Set the remote control lever in


Safety equipment Option makes it impossible to start the engine in anyother position than NEUTRAL.

4. Turn on the battery switch.5. Insert the key into the key switch and

turn the key to ON. If the alarm buzzersounds and alarm lamps come on, thealarm devices are normal.

Note: The cooling water temp. warninglamp does not come on.(See 2.5.1.(4))

6. Turn the key switch to start the engine.Release the key switch when the engine has started. The alarm buzzershould stop and the alarm lamps go out.





�� OFF position� ON position START position� GLOW position

(2) Starting Under Low TemperatureConditions

When starting the engine under difficultlow temperature conditions (approximately0°C or lower), use the air heater to enableeasier starting.

Option Do not leave the air heater on forlonger than 20 seconds at a time.Leaving the air heater on for longerperiods of time will result in damage.

Follow steps 1~4 of the above procedure,and then follow the steps below:5. Turn the key from the OFF position to

GLOW. Continue to hold the key in theGLOW position to allow the air heater towarm up the engine.

6. Turn the key to START and start theengine. After the engine starts, removeyour hand from the key.

(3) Restarting After Starting FailureBefore turning the key switch again, besure to confirm that the engine has stop-ped completely. If the engine is restartedwhile the engine still has not stopped, thepinion gear of the starter motor will bedamaged. When the engine will not startafter several attempts, check the fuelsystem. If there is air in the fuel system,the fuel will not be fed and starting will notbe possible.After bleeding air from the system, attemptto restart the engine. See 3.2.2

Turn the key for a maximum of 15seconds in the start position. If theengine does not start the first time,wait for about 1 minute before tryingagain.



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3.3.3 Operation

(1) Engine Acceleration and Deceleration

Use the governor handle to controlacceleration and deceleration. Move thehandle slowly.

(2) FORWARD–NEUTRAL(boat stopped) – REVERSE Clutch

Use the clutch handle to change fromFORWARD to NEUTRAL (boat stopped) toREVERSE.

Shifting the clutch while operating athigh speed or not pushing the handlefully into position (half clutch) willresult in damage to clutch parts andabnormal wear.

1. Before using the clutch, be sure to movethe governor handle to a low speedposition (less than 1000 rpm). Move thegovernor handle to a high speed positionafter completing clutch operation.

2. When changing between FORWARDand REVERSE, bring the clutch toNEUTRAL and pause before slowlyshifting to the desired position. Do notshift abruptly from FORWARD toREVERSE or vice versa.

3. Move the clutch handle accurately andfully into the FORWARD, NEUTRAL, andREVERSE positions.

3. Operation

(4) After the Engine has StartedAfter the engine has started, check thefollowing items at a low engine speed:

1. Check that the gauges and alarmdevices on the instrument panel arenormal.

2. Check for water or oil leakage from theengine.

3. Check that exhaust colour, engine vibra-tions and sound are normal.

4. When there are no problems, keep theengine at low speed with the boat stillstopped to send lube oil to all parts ofthe engine.

5. Check that sufficient cooling water isdischarged from the seawater outletpipe. Operation with too small seawaterdischarge will burn the impeller of theseawater pump. If seawater discharge istoo small, stop the engine immediately.Identify the cause and repair.• Is the Kingston cock open?• Is the inlet of the Kingston cock on

the hull bottom clogged?• Is the seawater suction hose broken,

or does the hose suck in air due to aloose joint?

The engine will seize if it is operatedwhen cooling seawater discharge istoo small or if load is applied withoutany warming up operation.


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3. Operation

(3) Switching to TrawlingUse the trawling handle to begin trawling.

1. Operation continues at a low enginespeed of 1000rpm or less.

2. Reduce the speed by moving thetrawling handle from H to L.Adjust the speed to the desired rate andsecure the trawling handle in place.

3. Before returning to normal operation, besure to move the trawling handle from Lto H.

Option KMH4A ClutchWhen trawling, do not raise theengine speed above 1000rpm, as thisresults in early wear of and damageto the clutch.

3.3.4 Cautions During Operation

Always be on the lookout for problemsduring engine operation. Pay particular attention to the following:

(1) Is sufficient water being dischargedfrom the seawater outlet pipe?

If the discharge is small, stop the engineimmediately, identify the cause and repair.

(2) Is the exhaust colour normal?The continuous emission of black exhaustindicates engine overloading. Thisshortens the engine’s life and should beavoided.(3) Are there abnormal vibrations or

noise?Depending on the hull structure, engineand hull resonance may suddenly becomegreat at a certain engine speed range,causing heavy vibrations. Avoid operationin this speed range. If you hear anyabnormal sounds, stop the engine andinspect.

(4) Alarm buzzer sounds during operation.

If the alarm buzzer sounds during opera-tion, lower the engine speed immediately,check the warning lamps, and stop theengine for repairs.

(5) Is there water, oil, or gas leakage, orare there any loose bolts?

Check the engine room periodically for anyproblems.

(6) Is there sufficient fuel oil in the fueloil tank?

Replenish fuel oil in advance to avoidrunning out of fuel during operation.

7) When operating the engine at lowspeed for long periods of time, racethe engine once every 2 hours.

Note: Racing the EngineWith the clutch in NEUTRAL, acceleratefrom the low speed position to the high


� H� L

� High speed (normal operation) � Low speed (trawling operation)

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4. Push the stop button on the instrumentpanel.

5. Turn the starter switch to OFF.6. Close the fuel tank cock.7. Close the Kingston cock.

Neglecting to close the Kingstoncock will allow water to leak into theboat and may cause it to sink. Besure to close the cock.

speed position and repeat this processabout 5 times. This is done to clean outcarbon from the cylinders and the fuelinjection valve.Neglecting to race the engine will resultin poor exhaust colour and reduceengine performance.

Electric OperationNever turn off the battery switchor spark the battery cable duringoperation. Damage to parts in theelectric system will result.

3.3.5 Stopping the Engine

Stop the engine in accordance with thefollowing procedures:

1. Put the remote control handle inNEUTRAL.

2. Be sure to race the engine beforestopping it. (See 3.3.4 (7))

3. Cool down the engine at low speed(approximately 1000 rpm) for about 5minutes.

Stopping the engine suddenly whileoperating at high speed will cause theengine temperature to rise quickly,causing deterioration of the oil andsticking of parts.



Stop button on the instrument panel

Engine stopping by stop button

3. Operation




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3. Operation

3.3.6 Procedure

The following diagram shows the procedures for operation explained up to this point.Parts of the operation may differ depending on the remote control system being used.Accompanying operation manuals should be read carefully and understood.

Inspection BeforeStarting

Starting the Engine

Driving Device ClutchClutch Remote ControlLever

Starter Switch� OFF � ON� ON � START


Alarm LampsInstrument Panel

Warming-up Operation

Speed LeverGovenor Remote ControlHandle

Stopping the Boat/Preparing to Stop theEngine

Speed LeverGovenor RemoteControl Handle

Driving Device ClutchClutch Remote ControlLever

Speed LeverGovenor RemoteControl Handle

Starting Operation

Driving Device ClutchClutch Remote ControlLever

Speed LeverGovenor RemoteControl Handle

Speed leverGovernor RemoteControl Handel

Driving Device ClutchClutch Remote ControlLever

Speed LeverGovenor RemoteControl Handle

Speed leverGovernor RemoteControl Handle

Cooling-down Operation

Engine Stop Button

Engine Stops

Engage ClutchForward or Reverse

Adjust Speed

Low Speed Position1000rpm or lower

Forward or Reverse

Adjust speed

Low Speed Position 1000rpm or lower

For 5 mins. or longer

Low Speed

High Speed


Trawling HandleTrawling Lever

Return to NormalOperation

Trawling HandleTrawling Lever


• Checking the AlarmDevices

• Turn the key for no longerthan 15 secs. Removehand from key afterstarting.

Checking for Problems

For 5 mins. or longer

Low Speed Position1000rpm or lower for5 mins. or longer

Checking the EngineDuring Operation

Low Speed Position1000rpm or lower

Put in Neutral

Low Speed � �High Speed

Racing the Engine

Repeat Several Times

KMH4A Clutch

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3.4 Long Term Storage(1) In cold temperatures or before longterm storage, be sure to drain the waterfrom the seawater cooling system.


Seawater System

If water is left inside, it may freezeand damage parts of the coolingsystem (fresh water cooler, sea-water pump, etc.) when ambienttemperature is below 0°C.

1. Loosen the drain cocks as illustrated,and drain off the water inside.



3. Operation

2. Loosen the 4 bolts fixing the side coverof the seawater pump, remove the coverand drain the water from inside. Retighten the bolts when finished.

3. Close the drain cocks.

(2) If antifreeze has not been added to thecooling fresh water, be sure to drain off thewater from the fresh water cooling systemdaily after use.

Fresh Water Cooling

If the water is not removed, it mayfreeze and damage parts of thecooling water system (fresh watercooler, cylinder block, cylinderhead, etc.) when ambient tempe-rature is below 0°C.

1. Open the water drain cocks asillustrated and drain the cooling water.

2. Close the drain cocks after draining thewater.


KMH4A Clutch4JH3-TE series

� Fresh water



4JH3-TE Series

4JH3-HTE/DTE Series

� Seawater

�� �

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3. Operation



(3) Carry out the next periodicinspection before placing the engine instorage. Clean the outside of the enginewiping off any dust or oil.

(4) To prevent condensation insidethe fuel tank, either drain off the fuel or fillthe tank.

(5) Grease the exposed area andjoints of the remote control cable and thebearings of the remote control handle.

(6) Cover the intake silencer, exhaustpipe, etc. with vinyl sheets and seal themto prevent moisture from entering.

(7) Drain bilge in the hull bottomcompletely. Water may leak into the boatwhen it is moored, and whenever possibleit should be landed.

(8) Waterproof the engine room toprevent rain and seawater from entering.

(9) During long term storage, chargethe battery once a month to compensatefor the battery’s self-discharge.

Checking the Engine for Reuse After aLong Storage Period

When using the engine after a long periodof storage, prepare for operation in thesame manner as for a new engine.See 3.3.1

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4. Maintenance & Inspection

4.1 General Inspection Rules

Conduct Periodic Inspection for YourSafety.The functions of engine components willdegenerate and engine performance willdrop according to the use of the engine. Ifcountermeasures are not taken, you mayencounter unexpected troubles whilecruising at sea. Consumption of fuel orlube oil may become excessive andexhaust gas and engine noise mayincrease. These all shorten the life of theengine. Daily and periodic inspection andservicing increase your safety at sea.

Inspect Before Starting.Make it a daily rule to inspect beforestarting. (See 3.3.1)

Periodic Inspections at Fixed Intervals.Periodic inspections must be made afterevery 50 hrs., every 250 hrs (1 yr.), every500 hrs. (2 yrs.), every 1000 hrs. (4 yrs.) ofuse. Conduct periodic inspectionsaccording to the procedures described inthis Operation Manual.

Use Genuine Parts.Be sure to use genuine parts for consumable and replacement parts. Use of other parts will reduce engineperformance and shorten the life of theengine.

Consult Your YANMAR Dealer orDistributor.Specialized technicians are ready to assistyou with periodic inspections and mainte-nance. Consult your YANMAR dealer ordistributor in accordance with the serviceagreement.

Servicing ToolsPrepare servicing tools onboard to beready for inspecting and servicing theengine and other equipment.

Tightening Torque of Bolts & NutsOver-tightening of bolts and nuts causesthem to come off or their threads to bedamaged. Insufficient tightening causes oilleakage from the installation face ortroubles due to the loosening of bolts.Bolts and nuts must be tightened to theappropriate tightening torque. Importantparts must be tightened with a torquewrench to the correct tightening torqueand in the right order. Consult with yourdealer or distributor if the servicingrequires the removal of such parts.

The standard tightening torque forstandard bolts & nuts is listed below.


Apply the following tightening torque to bolts having “7” on the head. (JIS strengthclassification: 7T) Tighten bolts with no “7” mark to 60% tightening torque.If the parts to be tightened are made from light alloy aluminum, tighten the bolts to 80%tightening torque.

Bolt dia. × pitch mm M6×1.0 M8×1.25 M10×1.5 M12×1.75 M14×1.5 M16×1.5

Tightening torque Nm 11 ± 01 26 ± 03 50 ± 05 90 ± 10 140 ± 15 230 ± 20

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4. Maintenance & Inspection


4.2 List of Periodic Inspection ItemsDaily and periodic inspections areimportant to keep the engine in its bestcondition. The following is a summary ofinspection and servicing items byinspection interval. Periodic inspectionintervals should vary depending on theuses, loads, fuels and lube oils used andhandling conditions, and are hard toestablish definitively. The following shouldbe treated as a general standard only.Section 4.3 gives a detailed explanation ofwhich parts must be inspected and theprocedure for doing so for each interval.

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4. Maintenance & Inspection


System Item Before After 50 Every Every Everystarting hrs or one 250 hrs 500 hrs 1000 hrs

month (1 year) (2 years) (4 years)

❍: Check �: Replace �: Consult local dealer

Fuel system


Cooling system

Air intake andexhaust system

Electrical system

Cylinder head,etc.

Remote controlsystem, etc.

Check the fuel level, and refill

Drain the fuel tank

Drain the fuel filter

Replace the fuel filter

Check the injection timing

Check the injection spray condition

Check the lube oil level

Replace the lube oil

Replace the engine lube oil filter

Wash the lube oil filter (Marine gear)

Clean the engine oil cooler

Clean the oil cooler (Marine gear)

Seawater outlet

Check cooling water level

Check the impeller of the cooling waterpump (seawater pump)

Replace the fresh water cooling

Clean & check the water passages

Clean the element of the air intake silencer

Clean the exhaust/water mixing elbow

Clean the breather pipe

Check the exhaust gas condition

Wash turbocharger blower

Check the alarm lamps & devices

Check the electrolyte level in the battery

Adjust the tension of the alternator driving belt

Check the wiring connectors

Check for leakage of water and oil

Retighten all major nuts and bolts

Adjust intake/exhaust valve clearance

Check/adjust the remote control operation

Adjust the propeller shaft alignment

❍ (first) ❍

� (first) �

� (first) �

� (first) �

❍ (first) ❍ ❍


❍ �

Every year


❍ (first) ❍ �

(After starting)

❍ (first) �

❍ ❍

❍ (first) ❍


Marine gear


Marine gear

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4. Maintenance & Inspection


(2) Replacing the Clutch Lube Oil andCleaning the Clutch Filter (1st time)

During initial operation, the oil is quicklycontaminated due to the initial wear ofinternal parts. The lube oil must thereforebe replaced early. 1. Remove the cap from the filler port and

attach the oil drain pump. Drain off oil.Clean the filter thoroughly withkerosene.

2. Fill with new lube oil. (See 3.2.4)3. Perform a trial run and check for oil


(3) Draining the (optional) Fuel TankOpen the drain cock and drain off anywater or dirt collected on the bottom. Put a pan under the drain to catch the fuel.Once the water and dirt has been drainedoff and the fuel coming out is clear, closethe drain cock.

(4) Inspection and Adjustment ofIntake/ Exhaust Valve HeadClearance (1st time)

Settling of a new engine and individualengine use will cause changes in theintake/exhaust valve and rocker arm clear-ance, and adjustment is necessary. Thisadjustment requires specialized knowledgeand techniques. Consult your Yanmardealer or distributor.

4.3 Periodic Inspection Items

4.3.1 Inspection on Initial 50 Hrs. ofOperation (or after 1 Month)

(1) Replacing the Engine Lube Oil andLube Filter (1st time)

During initial operation of the engine, theoil is quickly contaminated due to the initialwear of internal parts. The lube oil musttherefore be replaced early. Replace thelube oil filter at the same time. It is easiest and most effective to drain theengine lube oil after operation while theengine is still warm.

1. Remove the lube oil dipstick. Attach theoil drain pump and drain off oil.

2. Remove the lube oil filter with the filterdetach/attach tool. (Turn to the left.)

3. Clean the filter installation face andattach the new filter, tightening by hand.

4. Turn an additional 3/4 of a turn with theattachment tool. (Turn to the right.Tightening torque: 20 ~ 24 Nm)

5. Fill with new lube oil. (See 3.2.3)6. Perform a trial run and check for oil

leakage.7. Approximately 10 minutes after stopping

the engine, remove the oil dipstick andcheck the oil level. Add oil if the level istoo low.




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4. Maintenance & Inspection


(5) Adjusting the Tension of the Alter-nator Driving Belt.

When there is not enough tension in the V-belt, the alternator will not turn and powerwill not be generated.When there is too much tension in the V-belt, the belt will become damaged morequickly, and the alternator bearing may bedamaged.

1. Check the tension of the V-belt bypressing down on the middle of the beltwith your finger.With proper flexion, the V-belt shouldsink 8~10mm.

2. Loosen the set bolt and move the alter-nator to adjust V-belt tension.

3. Be careful not to get any oil on the V-belt. Oil on the belt causes slipping andstretching. Replace the belt if it is mar-red.

4.3.2 Inspection Every 50 Hours (or Monthly)

(1) Draining the Fuel Filter1. Close the fuel oil cock.2. Loosen the plug screw at the bottom of

the fuel filter oil/water separator, anddrain off any water and dirt collectedinside.Retighten the plug screw.

3. After reassembly, be sure to vent airfrom the fuel system. (See 3.2.2)

4. When there is a heavy deposit, drain thefuel tank at the same time.

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4. Maintenance & Inspection

cannot be raised by charging, the batterymust be replaced.

The capacities of the standardalternator and the recommendedbattery assume only the powernecessary for regular operation. If the power is also used for inboardlighting or other purposes, thegenerating and charging capacitiesmay be insufficient. In such cases,consult your Yanmar dealer ordistributor.

4.3.3 Inspection Every 250 hours.

(1) Replace the engine oil and theclutch lube oil.

After the second oil change, the engine oilshould be replaced after every 250 hours.

(2) Replacing the Engine Oil and LubeOil Filter

(See 4.3.1(1))

(3) Adjusting the Remote Control CableThe various control levers on the engineside are connected to the remote controllever by the remote control cable. Thecable will become stretched and theattachments loose after long hours of usecausing deviation. It is dangerous tocontrol operation under these conditions,and the remote control cable must bechecked and adjusted periodically.

A) Adjusting the Governor Remote ControlCable

Check to see that the control lever on theengine side moves to the high speed boltposition and low speed bolt position whenthe remote control lever is moved to H (high speed) and L (low speed) respec-tively.When there is deviation, loosen thebracket for the remote control cable on theengine side and adjust.

(2) Electric Operation

Fire due to Electric Short-Circuits


Battery Fluid

Before inspecting the electrical system,be sure either to turn off the batteryswitch or to disconnect the (-) terminalof the earth cable. Otherwise, a short-circuit could cause a fire.Ensure good ventilation when chargingthe battery. The use of open flames isstrictly prohibited. Hydrogen gas mayalso catch fire.Battery fluid is diluted sulfuric acid. Itcan blind you or burn your eyes or skin.Wear goggles and gloves when handlingbattery fluid. Should the fluid bedeposited on your skin, wash with alarge quantity of fresh water and seektreatment from a doctor.

1) If operation continues with insufficientbattery fluid, the battery will be destroyed.Check the fluid level periodically. If thelevel is lower than specified, resupplybattery fluid (available in the market) up tothe upper limit of the battery.(Battery fluid tends to evaporate in hightemperatures, especially in summer. Insuch cases, inspect the battery earlier thanspecified.)

2) If the engine speed will not rise and theengine cannot be started, measure thespecific gravity with a pycnometre (avail-able in the market).The specific gravity of the fluid when fullycharged is over 1.27(at 20°C).Fluid with a specific gravity of below 1.24needs charging. If the specific gravity




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Adjust the high speed bolt position firstand then adjust the low speed idling.

B) Adjusting the Clutch Remote ControlCable

Check to see that the control lever movesto the correct position when the remotecontrol handle is put in NEUTRAL,FORWARD, REVERSE.Use the NEUTRAL position as the stand-ard for adjustment. When there is devia-tion, loosen the bracket for the remotecontrol cable on the clutch side andadjust.

(4) Replacing the Fuel FilterWhen there is dirt in the fuel, the filter be-comes clogged, and the fuel will not floweasily. Check and replace the insideelement.

4. Maintenance & Inspection


1. Close the fuel cock.2. Remove the filter case by loosening the

retainer ring (turn to the left) with thefilter wrench.

3. Pull the element out from the bottom,and replace with a new one.

4. Clean the inside of the case thoroughly,put on the O-ring, and close with theretainer ring. (Turn to the right.Tightening torque: 12 Nm)

5. Air will enter into the fuel system whenthe filter is disassembled, and should bevented. (See 3.2.2)

(5) Cleaning the Intake SilencerDisassemble the intake silencer and cleanthe inside thoroughly.Remove the cover by taking off the clamp.Clean the element with a neutral detergent.Reassemble after it is completely dry.

(6) Adjusting the Tension of theAlternator Driving Belt

(See first 50 hrs.)

� Marine gear � Cable Adjustment

� Speed lever � Low speed High speed

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4. Maintenance & Inspection


(7) Inspecting Inner Parts of the Sea-water Pump

Depending on the use, the inside parts ofthe seawater pump deteriorate and dis-charge performance drops. At thespecified interval or when the volume ofseawater discharged is reduced, inspectthe seawater pump in accordance with thefollowing procedures:

1. Loosen the side cover set bolts andremove the side cover.

2. Illuminate the inside of the seawaterpump with a flashlight and inspect.

3. If any of the following problems isfound, disassembly and maintenanceare necessary:

a) Impeller blades are cracked or nicked.Edges or surfaces of the blades aremarred or scratched.

Note: The impeller must be replacedperiodically (every 1000 hrs.).

b) Wear plate is damaged.

4. If no damage is found when inspectingthe inside of the pump, reassemble theside cover.Fit the O-ring to the groove of the jointface before replacing the side cover.If a large amount of water leakscontinuously from the water drain pipebeneath the seawater pump duringoperation, disassembly and maintenance(replacement of the oil seal) arenecessary.When disassembly and maintenance ofthe seawater pump are necessary, con-sult your Yanmar dealer or distributor.

The seawater pump turns in thecounterclockwise direction, but theimpeller must be installed by turningin the clockwise direction. If theimpeller has been removed for anyreason and must be reassembled, bevery careful not to make a mistakeand turn it in the wrong direction.Additionally, if the engine is beingturned manually, be careful to turn itin the correct direction. Incorrectturning will twist the impeller anddamage it.

(8) Washing the Turbocharger Blower When engine revolution seems sluggish orthe exhaust colour poor, the blades of theturbocharger blower may be dirty. Washthe blower in the following manner:

1. Have ready blower wash (liquiddetergent), fresh water, and a smallpitcher.

2. Put the clutch in neutral and run theengine at high speed (2500~3000rpm).

3. Slowly pour approximately 50cc ofblower wash into the turbochargersuction inlet over a period of about 10 seconds.

Do not pour in a large amount ofblower wash at one time (pour it ingradually) as this can damage theblower blades and get water hammerin the combustion chamber leading toaccidents.

4. After about 3 minutes, pour inapproximately 50cc of fresh water in thesame manner over a period of about 10 seconds.



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4. Maintenance & Inspection



5. After operating the engine for about 10 minutes, check the boost pressureand power output.If there is no improvement after washingthe blower, repeat the washing processseveral times.If there is still no improvement consultyour local Yanmar dealer.

4.3.4 Inspection every 500 hrs.

(1) Draining the fuel tank.(See first 50 hrs.)

(2) Inspecting and Adjusting the FuelInjection Spray Condition.

Adjustment is necessary to obtain theoptimal fuel injection to ensure the bestpossible engine performance. This inspec-tion requires specialized knowledge andtechniques. Consult your Yanmar dealer ordistributor.

(3) Replace Driving Belt(See first 50 hrs.)

(4) Inspection and Adjustment of Intake/Exhaust Valve Clearance.

When operating for long periods of time,the clearance between the intake/exhaustvalve and the rocker arm will change andaffect operation performance. Adjustmentis necessary.

Adjustment requires specialized know-ledge and techniques. Consult your Yan-mar dealer or distributor.

(5) Adjusting the Remote Control Cable(See 4.3.2(3))

4.3.5 Inspection Every 1000 hrs.

(1) Inspecting and Adjusting the FuelInjection Timing

Fuel injection timing must be adjusted toensure optimal engine performance. This maintenance requires specializedknowledge. Consult your Yanmar dealer or distributor.

(2) Washing the Cooling Water Systemand Checking and Maintaining Parts

This maintenance requires specializedknowledge. Consult your Yanmar dealer ordistributor. Over time rust and scale buildsup in the seawater and fresh watersystems, reducing their coolingperformance. Additionally, when the insideof the engine oil cooler and the clutch oilcooler become dirty, lube oil coolingworsens causing the oil to deterioratemore quickly.Wash the following related parts when thecooling water is being replaced.Cooling water system related parts:seawater pump, engine oil cooler, clutchoil cooler, fresh water pump, fresh watercooler, thermostat, etc.

(3) Replace Impeller of Seawater Pump(See 250 hrs.)

� Blower wash � Inlet

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5. Trouble and Troubleshooting

Trouble Probable Cause Measure Reference

Alarm Buzzer and AlarmLamps On DuringOperation

Eng.Lube Oil Press.Warning Lamp goes on

C.W.Temp.(Fresh Water)warning lamp goes on

Faulty Warning Devices

C.W. Level Alarm Lampgoes on

Fuel Filter Alarm Lampgoes on

Exhaust Alarm Lamp goeson

One of the warning lampsdoes not go out

Charge lamp does not goout during operation(Buzzer does not sound)

Engine Lube Oil insufficient;Fuel filter clogged.

Insufficient water in fresh water cooler.Insufficient seawater causing temp. torise.Contamination inside cooling system.

Insufficient cooling water in fresh watertank.

Increased fuel filter drain.

Insufficient discharge of coolingseawater.Damaged cooling seawater pump.

Sensor switches faulty.

V-belt is loose or broken.Battery defective.Alternator power generator failure.

Check Lube Oil level. Replenish or replace.

Check cooling water and replenish.Check seawater system.Ask for repairs.

Check and replenish fresh coolingwater.

Drain the fuel filter.

Kingston cock is closed.Kingston cock is clogged.Suction hose is damaged or jointsare loose. Check seawater pump impeller.

Ask for repairs.

Replace V-belt; adjust tension.Check fluid level, specific gravity;replace.Ask for repairs.






*Note: Other warning lamps do not go on when the switch is turned on. They only go on when there is an abnormality.

Shift to low speed operation immediately, and check which lamp has come on. Stopthe engine for inspection. If no abnormality is identified and there is no problem withoperation, return to port at your lowest speed and request repairs.


Do not operate the engine if alarm devices are not repaired.Serious accidents may result if difficulties are not spotted due to faulty alarm lamps.When switch is turned ON:Alarm buzzer does not sound. Circuit broken or buzzer defective. Ask for repairs.


5.1 Trouble and Troubleshooting

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5. Trouble and Troubleshooting

Trouble Probable Cause Measure Reference

Starting Failures

Starter turns, but enginedoes not start

Starter does not turn orturns slowly(Engine can be turnedmanually)

Engine cannot be turnedmanually

Abnormal Exhaust ColourBlack smoke

White smoke

No fuel.Fuel filter is clogged.Improper fuel.Faulty fuel injection.Compression leakage fromintake/exhaust valve.

Faulty clutch position.Insufficient battery charge.Cable terminal contact failure.Faulty safety switch device.Faulty starter switch.Power lacking due to other use.

Internal parts seized; broken.

Load increased.Contaminated intake silencer.Boost pressure low.Improper fuel.Faulty spraying of fuel injection valve.Incorrect intake/exhaust valve headclearance.

Improper fuel.Faulty spraying of fuel injection valve.Fuel injection timing off.Lube oil burns; excessive consumption.

Replenish fuel; vent air.Replace element.Replace with recommended fuel.Ask for repairs.Ask for repairs.

Shift to NEUTRAL and start.Check fluid lever; recharge; replace.Remove rust from terminal; retighten.Ask for repairs.Ask for repairs.Ask for repairs.Consult your dealer.

Ask for repairs.

Inspect propeller.Clean element.Wash turbocharger blower.Replace with recommended fuel.Ask for repairs.Ask for repairs.

Ask for repairs.Ask for repairs.Ask for repairs.Ask for repairs.





When the clutch is broken KMH4A : See 5.2, Emergency Repairs forClutch Trouble.

5.2 Emergency Repairs for Clutch.KMH4A Marine Gear Only

In case of emergency, follow the followingprocedure for using the clutch emergencybolt to return to port.

• Using the emergency bolt directlyconnects the clutch to the enginemaking it possible to turn thepropeller. However, when the engineis started and the propeller turns, theboat will only move forward. Theneutral and reverse positions cannot

be used.The emergency bolt should only beused in cases where it is impossibleto operate the clutch and the boatmust return to port. Ask your Yanmardealer for repairs immediately afterreturning to port.

• When using the emergency bolt, neveruse the clutch as this will break it.

• Operate at low speed,1000rpm or less, and navigate carefully.When approaching the pierturn off the engine early and stop theboat.

Perform the following steps after turningoff the engine:1. Remove the hexagonal red bolts at the

back of the clutch with a spanner.



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5. Trouble and Troubleshooting


2. Check to see if the emergency bolt isvisible at the back of the bolt hole.When the emergency bolt is not visible,insert a turning stick little by little in theholes at the front side of the V-pulley,turning it in the direction of the crankshaft rotation and stopping when theemergency bolt becomes visible.

3. Inset the emergency bolt tightening toolinto the bolt hole and tighten theemergency bolt.

4. There are 2 emergency bolts.Follow the procedure described in 2 and3 for the second bolt, and tighten the

bolts alternately applying the sameamount of force to each.(Tightening torque: 19 ~ 01 Nm)

5. Replace the hexagonal bolt.6. Fill with the clutch oil set aside for

emergencies to the mouth of the fillerport. (When the oil pump is not working,there is no lubrication and filling with oilis essential.)

7. Start the engine with the clutch handlein neutral and proceed at low speed.

Consulting Your Yanmar Dealer or Distributor

Refer difficult problems and repairs to your Yanmar dealer or distributor.At the time of trouble, check and report the following:

1. Engine model and number:2. Boat name, material of hull, size (tons):3. Use, type of fishing done, no. of hours run:4. Total no. of operation hours (refer to hour metre), age of boat:5. Condition before trouble (engine rpm, type of operation, load condition, etc.):6. Details of trouble:

(exhaust colour; sound of engine; does engine start; can engine be turned manually;type of fuel used; brand and viscosity of lube oil; etc.)

7. Past problems and repairs:

� Turning stick direction � Emergency bolt tightening tool� Bolt (red)


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5. Trouble and Troubleshooting


Owner SatisfactionYour satisfaction and goodwill areimportant to us and to your dealer.Normally any problems concerning theproduct will be handled by our dealer’sservice department. If you have a warrantyproblem that has not been handled to yoursatisfaction, we suggest you take thefollowing action:

• Discuss your problem with a member ofthe dealership management.Complaints can often quickly beresolved at this level. If the problem hasalready been reviewed with the ServiceManager, contact the owner of thedealership or the General Manager.

• If your problem still has not beenresolved to your satisfaction, contactyour local Yanmar Subsidiary Com-pany. (See the back of this manual foraddresses)

We will need the following information inorder to assist you:

• Your name, address and telephonenumber

• Product model and serial number• Purchase date• Dealer’s name and address• Nature of the problem

After reviewing all the facts involved, youwill be advised of what action can beundertaken. Please remember that yourproblem will most likely be resolved at thedealership, using the dealer’s facilities,equipment and personnel. It is thereforevery important that your initial contact bewith the dealer.

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Page 49: Yanmar 4JH3 Operation Manual


Rubber hose

Steel pipe

Copper pipe

Screw joint (Union)

Flange joint

Eye joint

Insertion joint

Drill hole

Cooling fresh waterpiping

Cooling seawater piping

Lubricating oil piping

Fuel oil piping

6. Piping diagram(See appendix A at the back of this book)

01 Overflow02 Fuel oil inlet03 Piston cooling oil jet04 Fuel injection pump05 Lub. oil filter (cartridge type)06 Fuel high pressure pipe 07 Fuel injection nozzle08 Oil pressure switch09 Lub. oil cooler10 Mixing elbow11 Fresh water cooler12 Lub. oil inlet filter13 Main bearing14 Seawater inlet15 Cooling water pump (seawater)16 Hot water connection outlet17 Thermostat18 Cooling water pump (fresh

water)19 Hot water connection inlet20 Fresh water temperature

switch21 Lub. oil pump22 Pressure control valve23 Clutch lube oil cooler24 Turbo charger25 Seawater outlet26 Air cooler*27 Fuel oil filter (cartridge type)





NOTATION NOTES:Dimension of steel pipe: outer dia.x thicknessDimension of rubber pipe: inner dia. x thickness

Note: This piping diagram is for the4JH3E model.

* Not applicable (for the TE-model)

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7. Wiring diagrams (See appendix B at the back of this book)

Colour coding for wiring diagrams

R Red

B Black

W White

Y Yellow

L Blue

G Green

O Orange

Lg Light green

Lb Light blue

Br Brown

P Pink

Gr Grey

Pu Purple

For B/C-type panel01 Starter switch02 Stop switch03 Switch (lamp chk/illum.)04 Relay05 Relay (optional)06 Engine stop solenoid (optional)07 Procured by customer08 (Cross sectional area)09 Battery switch10 Battery11 Air heater12 Starter relay*13 Starter14 Cooling water temperature

switch15 Engine oil pressure switch16 Alternator17 Earth bolt18 Not applicable19 Tachometre sensor20 (Cooling water temperature

sender)21 Engine oil pressure sender22 Wire harness for 2 panel

(optional)23 Wire harness (optional)

24 Option25 Instrument panel26 Buzzer27 Tachometre28 Not applicable29 Oil pressure30 Cooling Fresh Water temp.31 Charge32 Switch (lamp chk/illum.)33 Starter switch34 Stop switch35 Instrument panel

(No.2 station)(optional) 36 Tachometre37 Buzzer38 Water proof39 Oil pressure40 Cooling Fresh Water temp.41 Charge42 Buzzer switch43 FUSE (3A)44 Eng. oil pressure metre45 Cooling water temp. metre46 Hour metre47 Illumination switch48 Cooling water temp.49 Eng. oil pressure

* Note: When using extension wireharnesses of more than 6m, the starterrelay connection is as shown here.

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1-32, Chayamachi, Kita-ku, Osaka, Japan • DESCRIPTION OF THE MACHINERY PARTS • CATEGORY: Diesel engine



Brugplein 11 1332 BS Almere-de Vaart, The Netherlands

Nagahama, Japan, Sept. 21, 1997 Place and date issued Y. Sugita Manager Quality Assurance Dept. Power System Operation Div.