6Aym-Wgt 6Aym-Wet 6Aym-Wst: Operation Manual

OPERATION MANUAL
MARINE PROPULSION ENGINE
6AYM
6AYM-WGT
6AYM-WET
6AYM-WST
en English
YANMAR
MARINE DIESEL ENGINE
OPERATION MANUAL
Thank you for purchasing a YANMAR Marine Diesel Engine.
[ lNTRODUCTION ]
ƔThis Operation Manual describes the operation, maintenance and inspection of
the YANMAR marine diesel engine.
ƔRead this Operation Manual carefully before operating the engine to ensure that
the engine is used correctly and that it stays in the best possible condition.
ƔKeep this Operation Manual in a convenient place for easy access.
ƔIf this Operation Manual is lost or damaged, order a new one from your
authorized YANMAR dealer or distributor.
ƔMake sure this manual is transferred to subsequent owners. This manual should
be considered a permanent part of the engine and remain with it.
ƔConstant efforts are made to improve the quality and performance of YANMAR
products, so some details included in this Operation Manual may differ slightly
from your engine. If you have any questions about such differences, please
contact your authorized YANMAR dealer or distributor.
ƔThe specifications and components (instrument panel, fuel tank, etc) described
in this manual may differ from the ones installed on your vessel.
Please refer to the manual provided by the manufacturer of these components.
Please review and comply with the applicable laws and regulations of the
international export control regimes at the territory or country where the product
and manual are intended to be imported and used.
MODEL 6AYM-WGT, 6AYM-WET, 6AYM-WST

OPERATION MANUAL
CODE 0A6AY-EN0043
All Rights Reserved, Copyright YANMAR POWER TECHNOLOGY CO., LTD.

6AYM-WGT_6AYM-WET_6AYM-WST.book 1 ページ２０１８年１２月７日　金曜日　午前１０時２４分
CONTENTS
FOR YOUR SAFETY ………………………………………………… 1
Safety Symbols ………………………………………………………………………… 1
Safety Precautions …………………………………………………………………… 2
Labels …………………………………………………………………………………… 5
Precautions for Lifting the Engine …………………………………………………… 7
Engine Nameplates …………………………………………………………………… 8
SPECIFICATIONS …………………………………………………… 9
Location of Components ……………………………………………………………… 10
FUEL OIL, LUBRICATING OIL AND COOLANT …………………11

Fuel ……………………………………………………………………………………… 11
Lubricating Oil ………………………………………………………………………… 12
Coolant ………………………………………………………………………………… 13
RUNNING-IN ……………………………………………………………14
Fuel ……………………………………………………………………………………… 14
Lubricating Oil ………………………………………………………………………… 16
Cooling System (Seawater and Coolant) …………………………………………… 17
Lubrication ……………………………………………………………………………… 19
Remote Control Device (Option)……………………………………………………… 19
Cranking ………………………………………………………………………………… 19
Instruments Check before Starting…………………………………………………… 20
Rechecking after Starting……………………………………………………………… 22
OPERATION ……………………………………………………………23
Starting ………………………………………………………………………………… 23
Air Motor Starting System (Option) ………………………………………………… 26
Notice while Running with Load ……………………………………………………… 27
Stopping ………………………………………………………………………………… 29
Long-Term Storage …………………………………………………………………… 30
CHECKING AND SERVICING THE TURBOCHARGER …………31

PERIODICAL MAINTENANCE ………………………………………32
Periodic Maintenance Schedule ……………………………………………………… 32
Fuel System …………………………………………………………………………… 34
Lubricating Oil System ………………………………………………………………… 35
Cooling Water System (Seawater and Coolant) …………………………………… 38
Turbocharger …………………………………………………………………………… 41
Injection Nozzle ………………………………………………………………………… 41
Remote Control Cables ……………………………………………………………… 42
Electrical Parts ………………………………………………………………………… 43
Valve Clearance Adjustment ………………………………………………………… 43
TROUBLESHOOTING AND COUNTERMEASURES ……………44

WIRING DIAGRAMS …………………………………………………49
YANMAR STANDARD MOTOR-DRIVEN BILGE PUMP
(OPTION) ………………………………………………………………53
FOR YOUR SAFETY 1
FOR YOUR SAFETY
Following the precautions described in this manual will enable you to use this engine with complete satisfaction. Fail-
ure to observe any of the rules and precautions, however, may result in injury, burns, fires and engine damage. Read
this manual carefully and be sure you fully understand it before beginning operation.
Safety Symbols
These are the warning signs used in this manual and on the product.
This safety alert symbol appears with most safety statements. It means attention, become alert, your
safety is involved! Please read and abide by the message that follows the safety alert symbol.
DANGER indicates a hazardous situation which, if not avoided, will result

DANGER in death or serious injury.
WARNING indicates a hazardous situation which, if not avoided, could

WARNING result in death or serious injury.
CAUTION indicates a hazardous situation which, if not avoided, could

CAUTION result in minor or moderate injury.
NOTICE indicates a situation which can cause damage to the machine,

NOTICE personal property and/or the environment or cause the equipment to operate
improperly.
2 FOR YOUR SAFETY
Safety Precautions
Safety precautions for operation
DANGER
Burns from steam
• Never remove the filler cap from the coolant tank while the engine is still hot.
Steam and hot air will spurt out and seriously burn you.
After engine stop, wait until the water temperature drops. Wrap a cloth around the filler cap
and slowly loosen the cap.
• After inspection, tighten the filler cap firmly.
If the cap is not secure, steam or hot air can spurt out during operation and seriously burn
you.
Ventilation of the battery area

• Make sure that the area around the battery is well-ventilated and that no flammable materials
are near.
The battery emits hydrogen gas during operation and charging. The gas can catch fire.
Fires from oil ignition

• Be sure to use the correct type of fuel oil. Always double-check before fueling.
The wrong fuel oils (e.g. gasoline) can cause a fire.
• Be sure to stop the engine before fueling.
If you spill fuel oil, wipe the spillage carefully.
• Keep oil and other inflammable materials away from the engine.
They can catch fire.
WARNING
Exhaust gas poisoning
• Never cover or block the windows, air vents, fans or other ventilation devices in the engine
room. Always maintain good ventilation in the engine room during operation.
Breathing exhaust gas is dangerous to your health.
Moving parts
• Keep your hands, other body parts and clothing away from moving parts (e.g. the front drive
shaft, V-belt or propeller shaft). You will get caught and injured.
• Never operate the engine without the covers on the moving parts.
• Before engine start, check that you removed all tools and cloths from the area near the
engine.
Alcohol and drugs

• Never operate the engine while you are under the influence of alcohol or drugs. Never oper-
ate the engine when you feel ill or unwell.
FOR YOUR SAFETY 3
CAUTION
Burns
• Be careful of burns. The entire engine is very hot during and after operation.
• Keep your hands, other body parts and clothing away from the exhaust manifold, exhaust
pipes, turbocharger, air cooler and engine body.
Safety precautions for maintenance
DANGER
Burns from steam
• Never remove the filler cap from the coolant tank while the engine is still hot.
Steam and hot air will spurt out and seriously burn you.
After engine stop, wait until the water temperature drops. Wrap a cloth around the filler cap
and slowly loosen the cap.
• After inspection, tighten the filler cap firmly.
If the cap is not secure, steam or hot air can spurt out during operation and seriously burn
you.
Fires from oil ignition

• Be sure to use the correct type of fuel oil. Always double-check before fueling.
The wrong fuel oils (e.g. gasoline) can cause a fire.
• Be sure to stop the engine before fueling.
If you spill fuel oil, wipe the spillage carefully.
• Keep oil and other inflammable materials away from the engine.
They can catch fire.
WARNING
Fires from electric short-circuits
• Always turn off the battery switch or detach the earth cable (-) before you inspect the electri-
cal system.
If you cause a short-circuit, a fire can occur.
Moving parts
• Stop the engine before you inspect it. If you have no choice but to inspect the engine while it
operates, keep your hands, other body parts and clothing away from rotating parts.
You will get caught and injured.
Exhaust gas poisoning

• Never cover or block the windows, air vents, fans or other ventilation devices in the engine
room. Always maintain good ventilation in the engine room during operation.
Breathing exhaust gas is dangerous to your health.
4 FOR YOUR SAFETY
WARNING
Side cover opening
• Do not open the side cover when the engine is hot. The new air intrusion may lead to an
explosion.
CAUTION
Battery fluid
• Be very careful not to expose your skin or eyes to the battery electrolyte.
The electrolyte is a strong acid and can cause inflammations.
If you come in contact with the battery fluid, wash it off immediately with a lot of freshwater.
Burns
• Be careful of burns. The entire engine is very hot during and after operation.
• Keep your hands, other body parts and clothing away from the exhaust manifold, exhaust
pipes, turbocharger, air cooler and engine body.
NOTICE
No modification
To keep the engine in good condition, the engine has been sealed to control the engine speed limit and the fuel
injection quantity. If a seal is removed, the sliding and moving parts of the engine will suffer from increased wear.
Engine performance will deteriorate and service life may shorten significantly. Removing a seal may also lead to
increased lubricating oil and fuel consumption, seizure and breakage in all portions of the engine. Therefore, do not
remove any seals. If the seal is removed, no warranty will be given even during the warranty period.
Regulation on NOx
Laws on maritime pollution and hazard prevention regulate the replacement of certain parts. The laws require that a
record and the signature of personnel who replaces these parts is kept. All inspections and maintenance must be
performed by our professional service technicians with the necessary expertise and skills.
Waste disposal
• Never dispose of waste oil, such as lubricating oil, by dumping it into a sewer, river, lake or ocean
waters.
• Do not spill waste oil into ocean waters. Use a container to collect waste oil from the engine.
• Comply with relevant laws and/or regulations for the disposal of hazardous materials such lubricat-
ing oil, fuel, filters or batteries.
FOR YOUR SAFETY 5
Labels
For safe operation, the affixed position of the labels is indicated.
Read the remarks of the labels carefully to attempt prevention of the accident.
Also, if you need to replace a part that has a label affixed to it, make sure you order the new part and label at the
same time.
If the labels are damaged or fallen, order them from your authorized YANMAR dealer or distributor.
■ Operation side
1 2 3
⁉″⁄⁀※⁀‹
4 5
停止後、1 0 分間は開けないで下さい。 No. Part No.

新気混入により爆発の恐れがあります。 1 128296-07260
Don’ t open1 0 min. after stop 2 148660-07770
C a n cause injury by explosion 3 141616-07210
4 141616-07200
5 135665-07210 016017-03X01
6 FOR YOUR SAFETY
■ Non-operation side
1 2 3
4 5
No. Part No.

1 041616-07220
2 129198-07350
3 148619-28990
4 148660-07770
5 141616-07210 016018-01X01
FOR YOUR SAFETY 7
Precautions for Lifting the Engine

The engine can cause serious injury when it falls during lifting. Obey the below instructions to prevent accidents
during lifting.
WARNING
• Make sure that the engine is lifted by qualified persons.
• Before lifting, make sure that the engine lifting bracket and mounting bolt have no damage and are in
good shape. If you find a fault, stop immediately and contact your authorized YANMAR dealer or distribu-
tor.
• Select lifting tools (e.g. wire rope and shackle) that are appropriate for heavy loads.
• Select the wire rope length so that the engine does not tilt during lifting.
• Before lifting, examine the lifting tools and make sure that they have no damage and are in good shape.
• Protect the parts of the engine or driven equipment that touch the wire rope with protective material.
• The tension of the wire rope changes depending on the lifting angle. Make sure that the angle is within
60°.
• If you use a marine gear that is not listed in this operation manual, separate the marine gear from the
engine, and lift the marine gear and engine separately.
• During lifting and moving the engine, do not go under the engine or near the engine.
• Do not lift the engine vertically or diagonally. Please check no damage to the lifter before lifting engine.
Within 60°
055132-00EN00
For the mass, refer to Specifications in the Operation Manual.

01-FOR YOUR SAFETY.fm 8 ページ２０２０年３月２３日　月曜日　午後５時９分
8 FOR YOUR SAFETY
Engine Nameplates
Periodic inspection and maintenance are important to help you enjoy your engine.
Your serial number is required at the time of requesting an engine maintenance or ordering a part. Confirm it before-
hand.
■ Location of engine nameplate:

It is affixed under the No.4 cylinder side cover of the cylinder block on the fuel injection pump side.
0RGHO
*HDU0RGHO
&RQWLQXRXVSRZHUN: kW/ min-1
6SHHGRISURSVKDIW min-1
)XHOVWRSSRZHUN:
(1*1R
037856-02X00
SPECIFICATIONS 9
SPECIFICATIONS
Model Unit 6AYM-WGT 6AYM-WET 6AYM-WST
Type – Vertical, 4-cycle, turbo-charged diesel engine
Combustion system – Direct injection
No. of cylinders – 6
Bore × stroke mm 155 × 180
Displacement l 20.379
Rating L M H H
Rated output
670/1938 610/1900 555/1840 485/1900
(flywheel output) kW/min-1
(911/1938) (829/1900) (755/1840) (659/1900)
(hp/rpm)
(2 hour rating) (10 hour rating) (24 hour rating) (24 hour rating)
Direction of rotation – Counterclockwise (Viewed from flywheel side)
Cooling system – Constant temperature cooling system (with heat exchanger)
Engine l 65
Coolant capacity
Reservoir tank l 3
Lubrication system – Forced lubrication with gear pump
Standard oil pan: 91

Engine l
Lubricating oil Shallow oil pan: 53
capacity
Marine gear l Refer to marine gear manual
Turbocharger type – Exhaust gas turbocharger (with air cooler)
Starting system – Electric starting or air starting
Engine mass
kg 2365
(without marine gear)
10 SPECIFICATIONS
Location of Components
■ Operation side
Intake manifold
Filler cap
Air cooler
Coolant tank
(Heat exchanger) Fuel filter
Seawater pump
Alternator
Governor
Fuel injection pump
Fuel priming pump
Fuel feed pump
Oil filler cap

Dipstick 016020-02E00
■ Non-operation side
Turbocharger
Exhaust manifold
Engine oil cooler
Water pump
(coolant)
Engine oil filter

Starter
Engine oil
bypass filter
016021-02E00
FUEL OIL, LUBRICATING OIL AND COOLANT 11
FUEL OIL, LUBRICATING OIL AND COOLANT
Fuel
The specification of fuel oil for this model is shown in the following table.
The properties of fuel are uncertain and broadly ranged; thus they affect such factors as a smooth run of the engine,
maintenance interval and service life of parts. Consequently, it might be necessary to change the specifications of
engine or add attachment in accordance with the applied fuel oil.
■ Quality criteria of fuel oil

Viscosity at 50 °C mm2/s 3-8
Specific gravity at 15 °C g/cm3 < 0.86
Flash point °C > 60
Residual carbon mass.% < 0.7
Sulfur content mass.% < 1.0
Property critical Ash content mass.% < 0.03
value Moisture content vol.% < 0.1
Vanadium ppm −
Sodium ppm −
Aluminum ppm −
Diesel index (Cetane no. of ≥ 45)
ASTM D975 2D
BS-2869 Class B1
Quality criteria equivalent fuel oil
ISO 8217 DMX
EN 590
NOTICE
The fuel injection system consists of precision parts and for that reason, do not use fuel to which water and dust are
mixed in. If such fuel is used, it causes a trouble. Consequently, pay attention to the following in supply of fuel.
Besides, as for daily maintenance, carry out draining and maintenance servicing of fuel filter mentioned in Periodic
Maintenance on page 32.
In time of fuel supply

• When supplying fuel stored in a drum, stand the drum still for longer than one whole day to settle the impurity, and
supply supernatant liquid of the drum to this engine.
• In the case of supplying fuel from a storage tank to the service tank, supply such fuel after more than one whole
day elapsed from when fuel is supplied to the storage tank.
12 FUEL OIL, LUBRICATING OIL AND COOLANT
Lubricating Oil
 Selection of lubricating oil is very important for a diesel engine. If improper lubricating oil is used or change of
lubricating oil is neglected, it causes sticking of piston rings, seizure or early wear of pistons and cylinder liners
and faster wear of bearings and various other moving parts that reduce the durability of the engine.
 Service categories
Use an engine oil that meets or exceeds the following guidelines and classifications:
• A.P.I. classification: Grade CD, CF
• SAE viscosity grade: 40, 15W-40
• T.B.N [mgKOH/g]: 9 - 15
Flash point Kinetic viscosity mm2/s (cSt)

Viscosity Specific Pour point Viscosity
Application (°C)
(SAE) gravity (°C) 40 °C 100 °C index
(open type)
Marine propul- 40 0.893 > 240 < -7.5 140 - 155 14 - 15.5 96 - 110
sion engine 15W-40 0.88 > 230 < -30 > 100 14 - 15.5 > 140
NOTICE
• Avoid blended use of different brands.
(In the unavoidable case of blended use of different brands of lub, consult your lubricating oil supplier.)
• If lubricating oil of a high total base number (T.B.N.) is used when using fuel oil of a low sulfur content, additive
(calcium carbonate) of lubricating oil sticks to the high-temperature area together with carbon residue and causes
adverse effects as mentioned below: For that reason, use the proper lubricating oil.
Accumulation of the aforementioned deposits on the combustion chamber hinders sliding of piston rings and may
cause scuffing to the rings, cylinder liners, etc. Besides, they may cause bite-in and blow-bye if intruded into
exhaust valves.
FUEL OIL, LUBRICATING OIL AND COOLANT 13
Coolant
■ Coolant selection
Use clean coolant (tap water) for the coolant.
Use the water having the properties shown in the following table.
Water quality for coolant

pH 298K (25 °C) 6.5 - 8.0
Total hardness (CaCO3) < 100 ppm
M alkalinity 30 - 100 ppm
Ammonium ion (NH4+) concentration < 0.05 ppm
Chloride ion (Cl-) concentration < 100 ppm
Sulfate ion (SO42-) concentration < 100 ppm
Evaporation residue < 400 ppm
■ Long Life Coolant (LLC) mixture selection

Always add Long Life Coolant (LLC) to the tap water. This mixture serves as the coolant.
YANMAR recommends the following Long Life Coolant (LLC):
• TEXACO LONG LIFE COOLANT/standard and premixed
Product Code 7997 and 7998
• HAVOLINE EXTENDED LIFE ANTIFREEZE/COOLANT
Product Code 7994
or equivalent to the above LLC.
NOTICE
Choose LLC which will not have any adverse effects on the materials (cast iron, aluminum, copper, etc.) used in the
engine’s cooling system, if different from the above.
Without this mixture, scale or rust is generated inside the parts of the coolant system, thus deteriorating cooling per-
formance. In winter, never neglect to us LLC in order to prevent freezing.
If LLC use is neglected, the cooling water freezes and expands inside the engine, resulting in breakage of parts in
the coolant system. The mixing ratio of LLC depends on the temperature. Be careful in using the mixing ratio speci-
fied by the manufacturer.
NOTICE
• Excess LLC deteriorates cooling performance.
A thin mixture which does not provide protection sufficient for the lowest temperature will freeze and damage the
cooling water system.
• Never mix different types (brands) of LLC, chemical reactions may make the LLC useless and engine trouble
could result.
14 RUNNING-IN
RUNNING-IN
When starting a new engine, perform the following procedure.
Fuel
Fuel filter
Fuel injection pump Over flow valve
Fuel oil return pipe

From fuel pump
Fuel priming pump

Approx.300 mm
Less than Fuel tank

500 mm Fuel feed pump
Approx.50 mm
Fuel/water Fuel oil cock Drain cock

Drain separating filter Separator
(To be added in the
case where fuel used
contains much dust
and other matters) 016022-00E
• Check the piping between the fuel tank and the engine as illustrated above.
• Be sure to install a drain cock at the bottom of the fuel tank to remove drain and a fuel/water separator (filter) in the
fuel piping.
• Make sure the inside of the fuel tank and fuel lines have been thoroughly cleaned.
• Fill the fuel tank with recommended fuel.
DANGER
• Use only diesel fuel. Never use other fuels, including gasoline, kerosene, etc., because they could cause a
fire. Be sure to check that you have selected diesel fuel before filling the fuel tank.
• Be sure to stop the engine and confirm that there are no open flames in the vicinity before supplying fuel.
• If you spill fuel, wipe such spillage carefully.
RUNNING-IN 15
Bleed the fuel oil system

If air enters the fuel system, the fuel injection pump Fuel/water separator (option)
does not work correctly.
Air bleed plug
Bleed the fuel system and obey the following proce-
dure when you fill fuel oil to the fuel tank for the first
time, perform maintenance (such as replacing the fuel
filter) of the fuel system, after the fuel oil has run out,
and there is a failure at startup.
1. Check the fuel oil level in the fuel tank and open
the fuel cock (or valve).
2. Loosen the air vent plug on the top of the fuel/
water separator (option). 000017-01E01
When fuel oil without air bubbles comes out of the

air vent plug hole, tighten the air vent plug.
3. Loosen the air vent plug on the top of the fuel filter. Fuel filter
4. Fill the fuel oil with the fuel priming pump.
1- The knob on the top of the priming pump rises
when you turn it counterclockwise.
2- Repeat moving the knob up and down continu-
ously by hand. Air bleed plug
Fuel oil with air bubbles comes out of the air
vent plug hole of the fuel filter.
5. When fuel oil without air bubbles comes out of the

000722-01E
air vent plug hole, tighten the air vent plug.
6. After you discharged air, screw the priming knob
tight while pressing it down. Priming pump
Move up
1 Loosen 2 and down
037098-00E00
2 Tighten
1 Press
037105-00E00
16 RUNNING-IN
Lubricating Oil
As it is necessary to keep oil level correctly, obey fol-
lowing procedure when you fill the engine lubricating
oil.
1. Remove the oil filler cap (1).
2. Fill recommended oil to the upper level mark on
the dipstick (2) while checking the level with the 1
2
dipstick (2).
Upper
Shallow oil pan 53 l
Oil capacity
Standard oil pan 91 l Lower
3. Install the oil filler cap.
NOTICE
013813-02E
• Be sure to stop the engine before refilling.
• When checking the oil level, insert the dipstick fully.
• Do not overfill with oil, as this may cause oil to
be sprayed out from the breather and damage
the engine.
4. Remove the oil filler plug (1) attached to the fuel

injection pump.
5. Fill with recommended lubrication oil to the pump.
6. Install the oil filler plug. 1
Fuel injection pump oil capacity 1.5 l
7. Fill the marine gear box with what the marine gear
manufacture recommended oil up to the proper
level.
014948-00X01
RUNNING-IN 17
Cooling System (Seawater and Coolant)

1. Be sure to check the condition of tighten all the
coolant drain cocks before filling coolant.
2. Remove the air vent plug on the thermostat cover
of the coolant tank.
3. Remove the filler cap of the coolant tank.
4. Fill the coolant tank with coolant up the filler neck.
5. Fill the reservoir tank with coolant up to the upper
level (FULL) mark.
Engine 65 l
Coolant capacity
Reservoir tank 3l
NOTICE
• Always fill with clean coolant.
• Always use coolant mixed with LLC.
6. Tighten the air vent plug on the thermostat cover.

7. Tighten the filler cap securely.
8. Check to be sure that the joint of the overflow pipe
between the reservoir tank and coolant tank are
securely tightened.
9. Tighten the side cover bolts of the seawater pump.
Cylinder block Water pump (coolant)
013819-00X 013822-00X
Exhaust manifold
013821-00X
013820-00X
18 RUNNING-IN
Air vent plug on the thermostat cover Coolant reservoir tank
FULL
FULL
LOW
LOW
001687-01E
013823-00X00
Coolant filler cap Seawater pump
close
open
000726-01X
001295-01E
RUNNING-IN 19
Lubrication
Apply grease to the lubricating points on the ball joints Governor
of remote control cable (for the governor).
Ball joint
013815-00X01
Remote Control Device (Option)

1. Operate the throttle handle from the position “L” to
the (full) position “H” and check that the governor
lever at the governor moves into correct position.
Adjust the control cable if necessary.
Unlock
2. Operate the shift handle into “AHEAD”, “NEU- Throttle handle Lock
TRAL” and “ASTERN” and check that the marine
gear control lever at the shift moves into correct High
positions.
NEUTRAL Low
Adjust the control cable if necessary.
AHEAD Shift handle
D
EA
AH
ASTERN
ASTERN
000044-03E04
Cranking
Oil reaches all moving parts of the engine sufficiently,
crank the engine according to the following procedure.
1. Open the sea cock.
2. Set the shift handle into the “NEUTRAL” position.
2
3. Set the throttle handle into the “L” position.
1
4. Turn the battery switch “ON”.
5. Start cranking. 3
1- Put the key in the starter switch and turn it to 2
the ON position.
2- Pull the engine stop lever or press the “STOP”
button of the instruments while turning the key 033955-02X00
to the START position to start the cranking.

3- Cranking time is 5 seconds; check for abnor-
mal sounds during that time.
Release your hand after cranking.
20 RUNNING-IN
Instruments Check before Starting

Turn the starter key to the “ON” position.
1. The needle of the oil pressure gauge should indicate “0”.
2. Make sure that the coolant temperature gauge operates properly.
3. The hourmeter should be working.
4. With the illumination switch ON, the illumination lamps of the LO. pressure gauge, the boost pressure gauge,
the tachometer, and the coolant temperature gauge should all come on.
1 2 3 4 5 6
8
12 11 10 9 032172-00X
1 - Boost pressure gauge 7 - Engine stop button

2 - Engine lubricating oil pressure gauge (Keep pressing until engine stops.)
3 - Coolant temperature gauge 8 - Starter switch
4 - Tachometer 9 - Buzzer
5 - Buzzer switch 10 - Clock
6 - Illumination switch 11 - Hourmeter
12 - Alarm display
Starter switch Stop button
4 During operation
1 Before starting
STOP
Release your hand
3 after starting
2 Starting
033955-00EN03
000003-01X
 Buzzer  Buzzer stop switch

If one of the alarm lamps mentioned on the next page The switch is used to pause the buzzer sound. Do not
comes on, the buzzer will sound intermittently. How- turn off the buzzer stop switch unless you check for a
ever, no buzzer will sound when the charge lamp and failure.
lubricating oil filter clogged alarm lamp comes on.
 Illumination switch
 Alarm lamps The switch is used to illuminate the instrument panel.
When any failure occurs, the corresponding alarm
lamp will come on.
RUNNING-IN 21
 Tachometer  Coolant temperature gauge

It shows the engine speed by min-1 (rpm). It shows the coolant temperature by °C (centigrade).
The read value can be used as a guide for judging the The red zone is caution and dangerous zone of high
load condition and the boat speed. temperature.
The read valve can be used as a guide for judging
 Hourmeter
whether the engine is cooling properly to prevent acci-
It shows accumulate operation time.
dents.
The read value can be used as a guide for periodic
maintenance checks. The information is displayed in a  Boost pressure gauge
window inside the tachometer. It shows the air pressure that flows to the combustion
 Engine lubricating oil pressure gauge chamber by 10-1 MPa.

The read value can be used as a guide for judging
It shows the engine oil pressure by 10-1 MPa. The red
whether the turbocharger is working properly to pre-
zone is caution and dangerous zone. The read value
vent accidents.
can be used as a guide for judging whether the engine
is lubricated properly to prevent accidents.
Alarm devices
BATTERY CHARGE LUBRICATING OIL FILTER CLOGGED
Comes on if the charge is abnormal. The ALARM LAMP
buzzer will not sound. Check for failures Comes on if the lubricating oil filter is clog-
such as a slip or broken V-belt in the alter- ging. The buzzer will not sound. Replace the
nator. filter element (cartridge) as soon as possi-
000092-01X 000097-01X
ble.
COOLANT TEMPERATURE HIGH ALARM MARINE GEAR LUBRICATING OIL
LAMP PRESSURE LOW ALARM LAMP
Comes on if the coolant temperature Comes on if the marine gear lubricating oil
becomes abnormally high. Continuous oper- pressure drops below the limit level. Contin-
ation at temperatures exceeding the maxi- uous operation with insufficient oil will result
000093-01X 000095-01X
mum will result in damage and seizure. in damage and seizure. Check the marine
Check the load and the water cooling sys- gear lubricating oil level. It is useful
tem for any abnormalities. if is coupled with YANMAR marine gear.
LUBRICATING OIL PRESSURE LOW ENGINE LUBRICATING OIL
ALARM LAMP TEMPERATUR HIGH ALARM LAMP
Comes on if the engine lubricating oil pres- Comes on if the engine lubricating oil tem-
sure drops below the lower level. Continu- perature becomes abnormally high. Contin-
ous operation with insufficient oil will result uous operation at temperatures exceeding
000094-01X 000098-01X
in damage and seizure. Check the oil level. the maximum will result in damage and sei-
zure. Check the failures in the seawater
cooling system.
COOLANT LEVEL LOW ALARM LAMP
Comes on if the coolant level drops below
the lower level. Continuous operation at
below the lower coolant level will rise the
coolant temperature and will result in dam-
000096-01X
age and seizure. Check the coolant level. In
addition, check that there is no leakage from
the cooling system.
030443-00X
22 RUNNING-IN
Rechecking after Starting

When a new engine is operated for the first time, the oil level of the oil pan will drop due to the engine oil circulating
to the oil cooler, oil filter, etc.
Therefore, stop the engine after operating for two to three minutes.
Wait for about five minutes and then check the following items:
• Check the engine oil level with the dipstick, and add oil up to the upper level if necessary.
• Check the marine gear oil level with the dipstick, and add oil up to the upper level if necessary.
• Check the coolant level of the coolant reservoir and the coolant tank.
Add coolant to the upper level if necessary.
DANGER
Never remove the filler cap when the engine is hot (above 60 °C).
The coolant is under pressure and severe scalding could result.
OPERATION 23
OPERATION
Prior to starting the engine, check to see if there is

nothing nearby the engine, particularly the rotating
parts that may cause damage.
Starting
Electric starter motor starting
1. Move the shift handle to the neutral position “N”.
2. Move the throttle handle to the position “L”.
 Before starting engine
1- Turn ON the battery switch.
2- Put the key in the starter switch. L
(Low speed)
Turn the key from the OFF to ON position and N
(Neutral)
check that alarm devices are shown in the
table “Normal function of alarm devices” on
D
EA
AH
ASTERN
page 24 are working properly.

• The buzzer sounds briefly (for approx. 1 sec-
ond).
014348-01E01
• The battery charge lamp should sequentially-
lighted; other alarm lamps should lighted and
off after approx. 3 seconds.
3. Turn it to the “START” position. Once the engine
Starter switch
starts, release your hand from the key. Then it will
return to the “ON” position automatically. With the
4 During operation
key in the “ON” position, the power source of the 1 Before starting
instruments and warning devices is engaged. Release your hand
3 after starting
2 Starting
NOTICE
• If the engine did not start, do not continue crank-
ing for longer than 15 seconds at any one
attempt. Allow at least 30 seconds of rest
between attempts. This will permit the battery to Normal start 033955-00EN02
recover and prevent to over heat the starter.
• When restarting, turn the starter switch after
stopping the engine completely.
If the starter switch is turned on before the
engine comes to a complete stop, serious dam-
age to the starting motor pinion and ring gear of
flywheel may result.
24 OPERATION
4. Checking the alarm devices just after starting

engine.
 Turn the key from the START to ON position and
check that alarm devices are shown in the table
below “Normal function of alarm devices” are
working properly.
• The buzzer stops.
• All alarm lamps go off.
By performing these procedures, it can be deter-
mined whether or not the electric circuit of the
buzzer and alarm lamps is in good working
order. If there is any problem, consult your
authorized YANMAR dealer or distributor for
investigation and repair.
Normal function of alarm devices

Starter switch opera- Before starting After starting
tion OFF→ON START→ON
Buzzers ON OFF
Alarm lamps
Battery charge lamp ON OFF
Coolant temperature ON briefly OFF
Engine lubricating oil
ON briefly OFF
pressure
Marine gear lubricat-
ON briefly OFF
ing oil pressure
Coolant level ON briefly OFF
Lubricating oil filter
ON briefly OFF
clogged
Engine lubricating oil
ON briefly OFF
temperature
OPERATION 25
Cold start (option)
■ Air heater operation

1. When starting during cold condition, first turn the starter switch to GLOW (for a few moments) to activate the
heater.
2. Next, after 20 - 30 seconds turn the starter switch to START. When the engine starts, the microcomputer catches
the engine revolution and activates the after-heater which remains on for 3 minutes.
3. The heater will operate for a maximum of 1 minute before the after-heat mechanism is activated. During this
period if the engine does not start, the after-heater will not be activated. Start the engine within 1 minute after
turning the key to “GLOW”.
4. When starting under normal conditions, the “GLOW” position is not used, and the heating mechanism is not acti-
vated.
GLOW : ON
60s Heater ON During this period if the charge lamp is ON,
the heater will go OFF after 60s.
GLOW : ON
60s Heater ON
During this period if the charge lamp is OFF,
the after-heater will go ON for 180s.
20s ~ 30s 10s
ignition 016025-00E01
■ Procedure
1. Put the shift handle in “N”.
2. Put the throttle handle at low idle position.
3. Turn the starter switch key to “GLOW” (for a moment).
4. After 30 seconds, turn the key to “START”, and the engine starts.
5. Release your hand from the key after starting; the key will return automatically to “ON”.
Notice after starting

 With the shift handle in the neutral position, observe the following instructions after starting.
• After starting, set the engine speed to 600 min-1 (600 rpm).
• Make sure that seawater is coming out from the cooling water (seawater) outlet.
• Check that the battery charge warning lamp (CHARGE) turning off consequently.
• Make sure that the coolant temperature gauge, on the instrument panel, reads 40 °C or more.
NOTICE
Do not turn off the key in the starter switch and the battery switch in the “OFF” position when operating the engine.
26 OPERATION
Air Motor Starting System (Option)

1. Make sure the air reservoir and the regulator valve are at the specified pressure.
Air reservoir: 2.45 - 2.94 MPa (25 - 30 kgf/cm2)
Regulator valve setting: 0.69 - 0.97 MPa (7.0 - 9.9 kgf/cm2)
2. Check the oil level in the oiler.
1- When supplying oil, remove the filler plug and add oil until it reaches the upper limit of the level gauge.
[capacity: 220 ml]
* When removing the bowl and supplying oil, loosen the filler plug to release the internal pressure.
2- When starting the engine, make sure that the inside of the adjusting dome is brimming with oil while the air
motor is running.
* The amount of oil to be applied to the air motor is adjusted by turning the adjusting dome. However, since
the adjusting dome has already been adjusted when shipped from the factory (one turn back from the
closed condition), it does not need to be adjusted. (Turning the adjusting dome counterclockwise allows the
amount of oil increase.)
■ Local starting
• Manual starting version: Open the quick valve and then close it immediately after the engine starts.
• Remote automatic starting version: Press the manual button on the starter solenoid. Release the button imme-
diately after the engine starts.
Oiler Quick valve

Adjusting dome
Filter plug
Air intermediate valve
(Option)
Level gauge (Operating air) (Primary air)
Ratchet
Air regulating
Bowl valve From air
compressor
Starting air motor
Air pressure gauge

(Operating air)
Air filter Air tank

Magnet valve
Ring gear
Silencer
Manual button
Flywheel
032333-00E
■ Air motor’s oiler oil selection

• Selection of air motor’s oiler oil is shown the following table. Oiler oil is based on the ambient temperature.
Temperature range Lubricating oil type

ISO VG32
5 to 60 °C
(e.g. Turbine oil #90)
ISO VG15
-15 to 5 °C
(e.g. #90 refrigerating machine oil)
OPERATION 27
Notice while Running with Load

While running the engine, pay attention to the following.
If problem occurs during operation, try to find the cause. If the cause cannot be found and the vessel is able to con-
tinue operation, return to port at a low speed. Consult your authorized YANMAR dealer or distributor after return.
■ Cooling water (seawater)

Make sure that water is coming out from the cooling water (seawater) outlet.
When water is coming out intermittently or in small volume, check the following.
• Air in the cooling system.
• Faulty cooling seawater pump impeller.
• Clogged cooling seawater pipe and sea cock.
NOTICE
Never operate the engine if the seawater pump is not sucking up water. The seawater pump impeller will seize and
become impossible to use again.
■ Coolant
Normally, the coolant temperature during running with load is 75 - 85 °C.
If the temperature exceeds 85 °C, check the following.
• Water leakage (temperature and coolant level warning devices may activate)
• Faulty water pump (coolant) or clogged coolant passage
• Faulty seawater pump or clogged seawater passage
• Insufficient coolant volume
• Heat exchanger restriction
■ Color of exhaust gas

Black smoke is a sign that the engine is overloaded. Such operation will shorten the life of intake and exhaust
valves, piston rings, cylinder liners, turbocharger and particularly fuel injection nozzles. Avoid continuing operation if
black smoke is being emitted.
■ Water leakage, oil leakage and other operational conditions

Always check whether there are water leakage, oil leakage, gas leaks, loose fasteners, and abnormal noise or tem-
perature, low oil pressure and vibration or not.
■ Avoid operating the engine speed at critical speed

Avoid operating the engine speed that produce resonance (critical speed). Depending on the construction of hull, the
engine and ship resonate at a certain rate of revolutions, and vibration may suddenly become great.
28 OPERATION
■ Alarm devices
When the buzzer sounds during engine running, at first check which alarm lamp is on, immediately set the engine
speed to low speed and stop the engine, and then try to find the cause.
■ Long time operation at low speed

When the engine is operated for more than 4 hours at low speed, set the shift handle to the “NEUTRAL” position,
and increase the engine speed without load for 1 minute at about 1800 min-1 (rpm) to discharge residue from cylin-
ders every 4 hours operation.
■ Operation of shift handle

Be sure to operate the throttle handle at a low speed (less than 1000 min-1 (rpm)).
If the marine gear is engaged or disengaged during high-speed or if it is used under half-clutch, the marine gear will
damage or its life will be shortened.
OPERATION 29
Stopping
To stop the engine, set the shift handle to the “NEUTRAL” position, and perform the after no-load running at a low
speed (600 - 700 min-1 (rpm)) for about five minutes.
NOTICE
If the engine stops at hot condition due to over heating, the temperature of the coolant and various engine parts will
rise abruptly, and the engine may be damaged.
1. Press and hold the STOP button or pull and hold the engine stop lever until engine has stopped.
2. Set the starter key switch to the “OFF” position after stopping engine.
3. Remove the key from the starter switch, and turn off the battery switch.
4. Close the fuel cock.
5. Close the sea cock.
6. While the engine is still warm, wipe off dust and dirt from the engine.
NOTICE
• Storing the engine without draining may cause the seawater left inside the engine to freeze and damage to parts
(heat exchanger, seawater pump) in the cooling water passage.
• Always use LLC in the coolant system.
30 OPERATION
Long-Term Storage
Storing engine for a long time
When the engine will not be used for a long term, perform the following.
Consult your authorized YANMAR dealer or distributors.
• Choose a dry, dust-free location for storage.
• In cold climate, make sure that you fully drain cooling coolant and seawater from both cooling systems.
• Loosen the V-belt.
• Disconnect the battery terminals from the engine, and store the battery fully charged. Charge the battery once a
month to compensate for the battery's self discharge.
• Remove any dirt, grime, or oil on the exterior and wipe it clean, and apply a coat of antirust agent or clean oil.
• Cover the exhaust pipe, intake, and electric devices with vinyl sheets to guard against moisture and dust.
Operating after long-term storage

Follow the steps below when restarting an engine which has been stored for 6 months or longer.
• Install full charged battery.
• Refer to [RUNNING-IN] before starting.
• Remove the rocker cover, and apply lubricating oil to the rocker arms.
• Check the cracks of the V-belt and adjust the V-belt tension.
• Check the damage of the impeller of the seawater pump.
• Perform cranking before operation to distribute lubricating oil to all of the parts.
CHECKING AND SERVICING THE TURBOCHARGER 31
CHECKING AND SERVICING THE TURBOCHARGER
■ Wash the pre-filter

A pre-filter removes contaminations in the air and
keeps the engine output in good condition.
1. Wash the pre-filter with a neutral detergent.
2. Wash the pre-filter with tap water, dry it sufficiently,
and install.
■ Wash the blower

If the turbocharger blower is contaminated, the blower
speed decreases and the boost pressure drops, caus-
ing the engine output to fall. Wash the blower, if the
boost pressure drops (approx. 10 % pressure drop
037121-02X00
compared with normal condition).
1. Prepare the blower wash fluid, freshwater, and oiler.
2. Remove the pre-filter from the intake silencer, and
remove the water filler plug.
3. During the load operation, fill 50cc of the blower
wash fluid slowly from the water filler in approx. 10
seconds.
4. Approx. 3 minutes after filling the blower wash
fluid, fill 50 cc of the freshwater from the water filler
in approx. 10 seconds.
5. Continue the load operation for approx. 10 minutes
to dry and check the output recovery.
6. Repeat the above washing operation for 3 to 4
times, if the performance is not recovered. Consult
your authorized YANMAR dealer or distributor for
repair.
When the boost pressure

Pre-Filter
drops by 10 % in compari-
Interval
son with the trial run. Or
Blower
every 250 hours.
037196-00X00
NOTICE
Do not fill a large amount of the wash fluid and fresh-
water at once. It may result in a water hammer acci-
dent.
32 PERIODICAL MAINTENANCE
PERIODICAL MAINTENANCE
• Periodical maintenance is an important factor in keeping the engine in the best condition. In accordance with oper-
ating hours given in the following maintenance schedule, perform periodic maintenance.
• When the parts are disassembled for checking and/or servicing, reassemble them properly.
• Please contact your authorized YANMAR dealer or distributor to inspect your engine or to replace any parts if you
will.
• Consult your authorized YANMAR dealers or distributor about scheduling the engine overhaul.
Periodic Maintenance Schedule

: Check : Replace : Consult your authorized YANMAR dealer or distributor.
Service period
Item Every Every Every Every Every Remarks
Daily
50 hrs 250 hrs 500 hrs 6 months year
Check fuel level and refill 

Fuel system
Drain fuel tank deposit and water

(When replenished)
Drain fuel filter 
Drain fuel-water separator deposit and water 
Replace fuel filter and fuel/water separator 
Check oil pressure 
Check oil level and refill (oil pan) 

Replace oil filter 
(1st time)
Lubrication system

Clean by-pass filter 
(1st time)
Clean oil cooler 
Gas (light) oil 
Standard
Diesel (heavy) oil 
Replace oil Per 300
Gas (light) oil 
(oil pan) running hrs.
Shallow
Per 150
Diesel (heavy) oil 
running hrs.
Check cooling seawater discharging condition 
seawater system
Replace seawater pump impeller 

Cooling
Check and replace zinc Heat exchanger  

anodes Air cooler  
Clean seawater system 
Check coolant temperature 
Check coolant level 
coolant system
Change coolant 
Cooling
Clean coolant system 

Check and clean thermostat 
Check water leakage from mechanical seal 
Replace if found
Replace mechanical seal 
water leakage
PERIODICAL MAINTENANCE 33
: Check : Replace : Consult your authorized YANMAR dealer or distributor.

Service period
Item Every Every Every Every Every Remarks
Daily
50 hrs 250 hrs 500 hrs 6 months year

Check injection timing 
(1st time)
Fuel injection pump
Check deflector 
and nozzle
Check major parts 


Check injection pressure and spray form 
(1st time)

Check nozzle carbon 
(1st time)
Replace injection nozzle 

Check and adjust valve clearance 
Cylinder
(1st time)
head
Check valve rotator, stem seal, valve spring 

Check oil feeding condition of rocker arm 
Crank- Fuel feed
pump
Replace oil seal 

Check oil leakage from oil seal 
shaft
Measure and adjust deflection 
Clean pre-filter and washing blower 

charger
Replace pre-filter 
Turbo
Check air/gas leakage 

Clean air cooler 
Check and adjust the governor link 

Check and adjust remote control cables 
(1st time)
Re-tighten hose clips

(Fuel, lubricatingoil, cooling water, breather and air 
(1st time)
line)
Check rubber hoses
(Fuel, lubricatingoil, cooling water, breather and air 
line)
Check tachometer 
Check alarm lamp 
Check battery electrolyte level and specific
Electric device

gravity
Check battery terminals 

Check alternator V-belt tension  
(1st time)
Check wire harness 
Check temperature and pressure switch 
Check looseness of bolts and nuts 
Exterior
Check water/oil/gas leakage at various parts 

Fuel System
(For fuel system diagram, refer to [Bleed the fuel oil
system] on page 15.)
■ Fuel level check

Service period Daily
Refill as required.
■ Fuel tank deposit draining

Open the drain cock on the tank to drain out sediment
and water at the tank bottom.
■ Fuel filter and fuel/water separator

draining
Remove the drain plug to drain water from the fuel filter
and fuel/water separator.
Service period Every 50 hours
■ Replace element of fuel filter and fuel/ Fuel filter

water separator Air bleed plug
Retainer
Loosen the bolt in the center of the fuel filter and

remove the filter case and element.
Replace the element with a new one. Case
When installing the new element and case, use new O- O-ring
rings; tighten the center bolt securely.

Element O-ring
NOTICE
• Before installing the element, clean the inside of the 000729-01E
filter case.
• Do not forget to install the spring, retainer and
O-rings. Fuel/water separator
• After replacing the element, be sure to bleed air from
Center bolt
the fuel system.
O-ring
Element
000054-01E
Lubricating Oil System

■ Oil level checking
Check the oil level with the dipstick. Oil level must be
maintained between the upper and lower level marks
on the dipstick. Add the recommended oil up to the
upper level mark, if necessary.
Service period Daily (prior to operation)
■ Replacement of oil filter

1. Remove the filter with the filter wrench. (Turn to the
left.)
2. Before installing the filter, carefully wipe the instal-
lation side and apply lubricating oil to the packing
surface.
3. Tighten the lubricating oil filter fully by hand, and
then use a filter wrench to further tighten the filter.
(Turn to the right.)
4. Check for oil leakage during operation.
1st time 50 hours 014350-00X00
Service
2nd time and
period Every 500 hours
after
■ Engine oil change

Wait for about one to two hours after stopping the
engine, connect the end of the rotary pump rubber
hose to the oil drain port, and drain oil. Fill the oil pan
with recommended oil.
1st time 50 hours

Every 500 hours
Standard (gas oil)
2nd oil pan Every 250 hours
Service
time (diesel oil)
period 000056-01X01
and Every 300 hours
after Shallow (gas oil)
oil pan Every 150 hours
(diesel oil)
■ Cleaning of lubricating oil bypass filter

The lubricating oil system is equipped with a lubricat-
ing oil bypass filter.
NOTICE
Stop the engine before cleaning the bypass filter.
If you disassemble the bypass filter while the engine is
running, oil mist may be blown off, causing burns.
Disassembly and cleaning
Service 1st time 50 hours

period 2nd time and after Every 250 hours
Cap nut
 Disassembly O-ring Thrust
collar
Disassemble and clean the lubricating oil bypass filter Spring
according to the following procedures. Cover
1. Loosen the cap nut and then remove the cover. Insulator
assembly
2. Loosen the nut and remove the rotor body. Nut
3. Loosen the lock nut and remove the rotor cover, Rotor body Lock
then remove the insulator and spring. Nozzle nut
4. Remove the sludge inside the rotor with a spatula. Rotor

O-ring cover
NOTICE O-ring
Completely remove the sludge. Otherwise,
Spindle shaft
residual sludge may cause an unbalance in
rotation, resulting in damage to the bearing of the
spindle shaft.
014205-02E
5. Check for clogging of the nozzle and clean the

nozzle a brass wire brush.
6. Check each part and the O-rings. If any damage or
excessive wear is found, replace the part.
 Assembly
Assemble the filter in the sequence reverse to disas-
sembly while observing the following precautions.
1. Install the insulator spring into the rotor body and
cover the rotor body with the rotor cover.
NOTICE
Ensure that the fitting of rotor and rotor cover is
secure. When the fitting is not aligned, the rotor
speed becomes unbalanced and it may damage
the equipment.
07-PERIODICAL MAINTENANCE.fm 37 ページ２０１８年１２月７日　金曜日　午前１０時４９分
2. Tighten the rotor cover to the rotor body with a lock

nut.
Lock nut tightening torque Hand-tighten
3. Insert the rotor to the spindle shaft and tighten the

nut by hand-tighten
Nut tightening torque Hand-tighten
4. Cover the cover, install the thrust collar (upper),

and tighten the cap nut.
Bypass filter (Part No. 148620-35310) (E/#: to 7071)
9.8 N•m (1.0 kgf•m) Or,

Tightening
after the tighten by hand fully,
torque of
use a spanner for M12 and
cap nut
tighten for 1 to 1-1/4 turns.
Bypass filter (Part No. 148620-35311) (E/#: from 7072)
16 ± 2 N•m (1.6 ± 0.2 kgf•m) Or,

Tightening
after the cap nut is attached,
torque of
use a spanner for M12 and
cap nut
tighten for 1 to 1-1/4 turns.
NOTICE
Avoid overtightening the nut and cap nut. When
the cap nut is overtightened, the tightening power
is lost during loosening at the next time and it may
cause the spindle shaft to loosen.
5. While operating the filter, make sure oil does not

leak from connected sections. Also, make sure the
filter is not vibrating abnormally.
Cooling Water System (Seawater and Coolant)

Seawater system
■ Discharging seawater
From time to time during operation, check if water is
coming out of the seawater outlet pipe. If water comes
out intermittently or its volume is low during a high-
speed run, stop the engine immediately, and check for
the cause.
Service period Daily (durings operation)
■ Checking and replacement of zinc

Heat exchanger
anodes
Remove the zinc anode and scrape or remove with a
wire brush the coating on the zincs. If more than 50 %
of the zinc is corroded away, it should be replaced with
new zinc.
Zinc anodes are built into the following places:
Q’ty
Heat exchanger .............................................. 4
Air cooler ........................................................ 4
013295-01X
Service Checking Every 250 hours

Air cooler
period Replacement Every 500 hours
013300-01X
■ Replacement of seawater pump impeller

1. Remove the seawater pump cover and pull out the Impeller
O-ring
impeller. Check the wear plate and cover for wear Cover
or damage.
2. If the wear plate and cover are excessively worn,
replace them with new ones.
3. When reassembling the pump, apply grease to the
fitting area of the pump shaft and impeller, both
end faces of the impeller and the tip of impeller
blades. 000728-01E
4. When installing the impeller, position blades of the

impeller as shown in the illustration at right. Impeller
Service period Every year
■ Seawater system cleaning

As the engine is used, coolers become foul, their cool-
ing effect worsens, and coolant and intake air tempera-
ture becomes abnormally high.
Consequently, eliminate fouling of the seawater sys- 000984-01E
tem, coolers in particular.

To clean the seawater system, consult your authorized
YANMAR dealer or distributor.

Coolant system
■ Coolant level checking

Check the coolant level before starting the engine in
the cold condition.
1. Remove the filler cap from the coolant tank, and
check coolant level.
The level should be at the filler neck. If the level is
low, add coolant up to the filler neck.
DANGER
Do not remove the filler cap when the engine is
hot (above 60 °C).
The coolant is under pressure and severe
scalding could result.
2. On the coolant system with reservoir tank, check

the coolant level in the reservoir tank. The level
should be between the “FULL” and “LOW” level
marks. Add coolant up to the “FULL” mark.
■ Water pump (coolant) leakage checking

Leakage of coolant may cause serious problems, such
as seizure of the engine, as the volume of coolant
decreases.
If there is water leakage, consult your authorized YAN-
MAR dealer or distributor.
■ Coolant system cleaning

As the coolant system becomes dirty naturally, cooling
efficiency worsens, and coolant temperature becomes
abnormally high (above 85 °C) when the engine is
operated for long time: clean the coolant system peri-
odically. At the same time, clean the thermostats. As
for periodic servicing, consult your authorized YAN-
MAR dealer or distributor.

■ Coolant change
NOTICE
• Be sure to replace the coolant at the specified time.
• Be sure to follow the correct mixture ratio for Long
Life Coolant (LLC). (Refer to [Coolant])
Turbocharger
■ Clearing of prefilter and turbocharger
Refer to [CHECKING AND SERVICING THE TURBO-
CHARGER].
■ Checking each joint area

Check the turbocharger-to-charge air cooler and turbo-
charger-to-exhaust manifold connections for damage
or leaks.
Injection Nozzle
■ Replacement
Remove the injection nozzle, and replace it with a new
one.
Consult your authorized YANMAR dealer or distributor.

Remote Control Cables

■ Throttle handle
Operate the throttle handle from the position “L” to the Unlock
Throttle handle
position “H”, and check if the governor lever at the gov- Lock
ernor moves into the correct position. If there is dis-

High
alignment between the throttle handle and the
governor lever in their position, adjust the control cable Low
NEUTRAL
by changing the clamping position of the bracket. AHEAD Shift handle
D
EA
AH
ASTERN
ASTERN
■ Shift handle
Check if the control lever at the marine gear moves 000044-03E04
when the shift handle is operated in the ahead, neutral

and astern positions. If there is a disalignment
between the lever and the handle, adjust the control
cable by changing the clamping position of the bracket.
Remote control cable
Service 1st time 50 hours

period 2nd time Every 6 months
Bracket
016504-00E00
Electrical Parts
■ Checking the alarm devices
■ Checking the battery fluid level

Insufficient Proper Excessive
Battery electrolyte decreases as charging and dis-
charging are repeated. Check normal electrolyte level
is 10 - 20 mm above the pole plates. If level is low, add
distilled water, refer to the illustration at right. 016089-00E
■ The alternator drive belt tension

1st time After 50 hours
Checking 1
2nd time Every 500
Service
and after hours
period m
Replacing 5
m
Every year 22
V-belt
3.6 mm
Squarely add load 7.5 N (for a new belt) to the center

part of the belt span, and adjust for the deflection at
that time to become 3.6 mm. (6.5 N when trying to put)
(Adjust for the deflection to become 1.6 mm per 100
mm span length.) 2
 Adjusting the V-belt
052880-00X02
1. Loosen the lock bolt (1) of the alternator. Adjust the

tension of the V-belt with the adjuster nut (2).
2. After you adjust, tighten the adjuster nut (2) and
the lock bolt (1) of the alternator.
3. Replace the V-belt if it is damaged.
Valve Clearance Adjustment

Consult your authorized YANMAR dealer or distributor
about adjusting the valve clearance.
Intake 0.3 mm
Valve clearance
Exhaust 0.5 mm
1st time 50 hours
Service period
2nd time Every 6 months
44 TROUBLESHOOTING AND COUNTERMEASURES
TROUBLESHOOTING AND COUNTERMEASURES
The causes of abnormalities and troubles are diverse, and they break out from composite factors.
Catching a change in running performance and referring to the record of maintenance and servicing date and the
history of part replacement, locate the cause early and take the proper countermeasures.
 Starting failure
Flywheel not turned
Flywheel turned, but ignition not taken place
 Rotational speed dropped spontaneously
 Output of each cylinder not in uniformity
(Dispersion of the exhaust temperature is large among cylinders)
 Bad color of exhaust gas
 Lubricating oil pressure dropped below the specified pressure
 Unusual sounds heard (knocking occurred) during operation
 Coolant temperature too high
 Exhaust temperatures of all the cylinders too high
 Engine stopped suddenly
NOTICE
• Although some failures can be solved by the user, others are not. For failures that require disassembly for repair
and servicing or those that are not covered in this chapter, consult your authorized YANMAR dealer or distributor.
• If you judge that you can continue using the engine after inspection, cruise at a slow speed to return to port and,
when landed, ask for repairs. If you cannot judge on your own, ask your authorized YANMAR dealer or distributor.
• Do not operate the engine if alarm devices are not working properly. Doing so may lead to a severe accident in
case of a failure because you will not receive any alarm notifications.
TROUBLESHOOTING AND COUNTERMEASURES 45
Starting failure
Flywheel not turned

Cause Countermeasure
1. Electric starting system
• Battery voltage drop Charge the battery.
• Failure of starter motor Consult your authorized YANMAR dealer or distributor.
2. Air starting system
• Clogging of air filter or silencer Check and clean the filter or silencer.
• Failure of air starter Consult your authorized YANMAR dealer or distributor.
3. Too high viscosity of lubricating oil Change the correct lubricating oil with a low-viscosity one.
4. Seizure of moving part
• Seizure of piston and cylinder liner Consult your authorized YANMAR dealer or distributor.
• Seizure of main bearing and/or camshaft bearing Consult your authorized YANMAR dealer or distributor.
Flywheel turned, but ignition not taken place

1. Fuel oil not sent under pressure to fuel injection pump
• Fuel tank empty Supply the fuel to the fuel tank.
• Closing of fuel cock (valve) Open fuel cock (valve).
• Clogging of fuel filter Replace the filter element.
• Failure of fuel feed pump Consult your authorized YANMAR dealer or distributor.
• Air mixed in fuel system Check and repair the fuel system, then bleed air.
2. Poor airtightness of intake/exhaust valve
• Inadequate intake/exhaust valve clearance Consult your authorized YANMAR dealer or distributor.
• Sticking of intake/exhaust valve Consult your authorized YANMAR dealer or distributor.
• Damage of seat of intake/exhaust valve Consult your authorized YANMAR dealer or distributor.
3. Low cetane number of fuel oil Use a high- quality fuel oil.
Rotational speed dropped spontaneously

1. Clogging of fuel filter Replace the filter element.
2. Seizure of moving part Consult your authorized YANMAR dealer or distributor.
(piston, main bearing or turbocharger)
3. Air mixed in fuel system Check and repair the fuel system, then bleed air.
4. Moisture content in fuel system Drain the filter, tank, etc.
Output of each cylinder not in uniformity

(Dispersion of the exhaust temperature is large among cylinders)
1. Air mixed in fuel system Check and repair the fuel system, then bleed air.
2. Moisture content in fuel system Drain the filter, tank, etc.
3. Fuel injection volume not in uniformity among cylinders Consult your authorized YANMAR dealer or distributor.
Bad color of exhaust gas

1. Inadequate fuel injection timing Consult your authorized YANMAR dealer or distributor.
2. Inadequate intake/exhaust valve clearance or damage of Consult your authorized YANMAR dealer or distributor.
intake/exhaust valve seat
3. Sticking of intake/exhaust valve Consult your authorized YANMAR dealer or distributor.
4. Damage of intake/exhaust cam Consult your authorized YANMAR dealer or distributor.
5. Defect of turbocharger
• Clogging of pre-filter Wash the pre-filter.
• Fouling of the blower side or turbine side Wash the turbocharger/blower.
6. Fouling of charge air cooler (too high temperature of boost Consult your authorized YANMAR dealer or distributor.
air)
7. Low-quality of fuel oil Use a high-quality fuel oil.
8. Overload Reduce the load.
TROUBLESHOOTING AND COUNTERMEASURES 47
Lubricating oil pressure dropped below the specified pressure

1. Looseness of lubricating oil pipe Check and repair the lubricating oil pipe.
2. Clogging of lubricating oil filter Replace the lubricating oil filter.
3. Excessive clearance of crankshaft bearing Consult your authorized YANMAR dealer or distributor.
4. Sticking of lubricating oil pressure regulating valve or loose Consult your authorized YANMAR dealer or distributor.
adjusting bolt
5. Sticking of lubricating oil safety valve Consult your authorized YANMAR dealer or distributor.
6. Too high temperature of lubricating oil
• Shortage of cooling water volume Check the water pump (coolant).
• Fouling of lubricating oil cooler Consult your authorized YANMAR dealer or distributor.
• Excessive blow-bye (gas leak) into the crankcase Consult your authorized YANMAR dealer or distributor.
7. Air sucked in lubricating oil pump (shortage of lubricating oil Replenish the lubricating oil.
volume)
Unusual sounds heard (knocking occurred) during operation

1. Inadequate intake/exhaust valve clearance Consult your authorized YANMAR dealer or distributor.
2. Inadequate fuel injection timing Consult your authorized YANMAR dealer or distributor.
3. Loosen some parts Check and fix.
Coolant temperature too high

1. Shortage of cooling water volume
• Clogging of seawater inlet passage Check and clean the seawater strainer, sea cock and pipes.
• Failure of seawater pump impeller Check and repair the impeller.
• Failure of water pump (coolant) Consult your authorized YANMAR dealer or distributor.
2. Coolant level is low. Refill with coolant.
3. Coolant is leaking. Check and tighten the leaking part.
4. Sticking of coolant thermostatic valve Consult your authorized YANMAR dealer or distributor.
Exhaust temperature of all the cylinders too high

1. Charge air temperature too high
• Shortage of charge air cooler cooling water volume Check and repair the seawater pump.
• Fouling of charge air cooler (cooling water side and air Consult your authorized YANMAR dealer or distributor.
side)
• Engine room temperature too high Check and service the engine room ventilation equipment.
2. Boost pressure too high
• Engine room put under a negative pressure Check and service the engine room ventilation equipment.
3. Unsuitable properties of fuel oil Use a high-quality fuel oil.
4. Overload Reduce the load.
Engine stopped suddenly

1. Fuel tank empty Replenish the fuel oil.
2. Air mixed in fuel system Bleed air from the fuel system.
3. Clogging of fuel filter Replace the filter element.
4. Seizure of moving part (piston, main bearing, crank-pin Consult your authorized YANMAR dealer or distributor.
bearing, timing gear, etc.)
Color coding
R Red Lg Light green
Starter switch
B Black Lb Light blue
W White Br Brown 30 AC 17 G1 G2 P1 P2 AR LR LR
Y Yellow P Pink GLOW L

LY
L Blue Gr Gray OFF A B
B
6AYM-WGT_6AYM-WET_6AYM-WST.book
ON M P2 P1
G Green Pu Purple
START
O Orange E Relay
LW LW Battery Battery
+ - + -
Engine stop motor ( DC24V, 240AH )

49 ページ
Boost pressure L.O.P C.W. temp Tacho. with Buzzer Buzzer Illumi.
gauge gauge gauge hour meter stop B Battery switch B
BZ WBr
+ - + - +- U 5W C
+- P Starter
B
RG
Starting relay
RW
OG
RG
GrB
5R B
5R
GrB LW
RG RG LY (Not use)
B L 3R
YW 5B
G GR
WL
B
5R
B
Y YR
Fuse Stop button E
RG RG B
WIRING DIAGRAMS
3A
RB W WBr R
L Earth bolt
IGN RG IGN RG LB
GND B GND B
Y YR O C.W. temp. switch L.O. pressure
+ + WB Starter switch switch Alternator
- G - GR
W WG WG AC 3R B
+7V +7V 30
YB YG
3P-F
3P-F
YB
3P-M
GB
3P-M
SENSOR SENSOR 17 P1
RB
B
GB P2 AR
O B Option
RW G2 3L WR
OG G1 Y
3W WB
２０１８年１２月７日　金曜日　午前１０時２４分
8P-F
8P-F
8P-M
8P-M
LB
Lb
Charge LB RG RG C.W.temp. sender L.O. oil temp. C.W. level sensor Tacho sensor. M/G oil pressure
B switch switch
L.O. press YW YW YW
C.W. temp. WL WL WL
Alarm O
M/G.oil p. YG YB
circuit
8P-F
8P-F
8P-M
8P-M
YG unit YG GB
C.W. level WR WR
WR
L.O. temp. Y Y Y WG
G G B
L.O. filter G
G
Wire harness
■ 24 V engine negative ground type without air heater (standard)
Boost sensor L.O. pressure

sensor
Instrument panel L.O. filter bypass valve switch
3R 3W YW WL WG B WB YR Y WR
3L RB LB O YG YB GB G GR
(3P-M) (8P-F) (8P-M)

WIRING DIAGRAMS
Detail of connector (arrow A-A)

Engine negative ground
016093-03EN00
49
L.O.P C.W. temp Tacho. with Buzzer Buzzer Illumi.
50
gauge gauge hour meter stop
BZ
+ - +- U +- P
RW
RG
OG
B
GrB
RG
LW
LY Relay
GrB (Not use)
RG RG L
B
GR LR LR
B Fuse
YR Stop button L
RG 3A RB W WBr LY
㹕 A B
B
B
IGN RG
B Starter switch M P2 P1 Battery Battery
GND O
+ YR
GR WB AC 3R E Relay + - + -
- LW LW
3P-F
WG
3P-M
+7V 17 P1 30
50 ページ
RB
SENSOR YB YB P2 AR (DC24V, 240AH)
RW G2 G1 3L
OG 3W Engine stop motor
RG RG RG
L.O. press Battery switch
8P-F
YW
8P-M
B
C.W. temp. YW YW Wire harness
WL WL WL
M/G.oil p. Alarm B B
WIRING DIAGRAMS
YG O
C.W. level
circuit WBr
WR YG unit YG
L.O. temp. Y WR WR 5W C
Y Y Starting relay Starter
8P-F
8P-M
L.O. flter G G G 5R B
Instrument panel (Sub) 5R
LW
L.O.P C.W. temp Tacho. with Buzzer Buzzer Illumi. LY 3R
L
(Not use)
Boost meter gauge gauge hour meter stop 5B
YW
BZ WL
5R
+ - + - +- U +- P E
RG
B
RG
OG
RW
GrB
Fuse Stop button B
3A RB W R
㹕 Earth bolt
GrB L
RG RG LB
B
C.W. temp switch L.O. pressure
G GR Starter switch switch Alternator
B B O
Y YR AC 3R B
RG RG RW YG
3P-F
3P-F
3P-M
3P-M
OG 17 P1 30
RB
B
P2 AR
RG RG WB O B Option
IGN IGN 3L WR
B B G2 G1
GND Y GND YR Y
+ + 3W WB
- G - GR
+7V W +7V WG WG
SENSOR GB SENSOR YB YB
GB
8P-F
8P-F
8P-M
8P-M
C.W. temp sender L.O. temp. C.W. level sensor Tacho. sendor M/G oil pressure
LB switch switch
Lb
Charge LB RG RG
L.O. press B
YW YB
8P-F
8P-F
8P-M
YW
8P-M
YW
C.W. temp. WL WL GB
WL
Alarm O
M/G.oil p. YG WG
YG circuit YG B
C.W. level WR unit
WR WR G
L.O. temp. Y Y Y
G G
L.O. flter G
sensor
■ 24 V engine negative ground type without air heater (tow-place gauge)
Instrument panel (Main) L.O. filter bypass

valve switch
Color coding 3R 3W YW WL WG B WB YR Y WR
R Red Lg Light green 3L RB LB O YG YB GB G GR
B Black Lb Light blue Starter switch (3P-M) (8P-F) (8P-M)
W White Br Brown 30 AC 17 G1 G2 P1 P2 AR
Y Yellow P Pink Detail of connector ( arrow A-A )
GLOW
L Blue Gr Gray OFF
G Green Pu Purple ON Engine negative ground
O Orange START
016094-03E00
Color coding
R Red Lg Light green
B Black Lb Light blue Starter switch
Brown LR LR
W White Br
30 AC 17 G1 G2 P1 P2 AR
Y Yellow P Pink L
GLOW LY
L Blue Gr Gray A B
OFF B
G Green Pu Purple ON M P2 P1
O Orange START E Relay
LW LW Battery Battery
+ - + -
Engine stop motor (DC24 V)
51 ページ
Boost pressure L.O.P C.W. temp Tacho. with Buzzer Buzzer Battery switch
Illumi. LR
gauge gauge gauge hour meter stop B B
BZ WBr
+ - + - +- U 5W C
+- P Starting relay Starter
RW
RG
OG
B
GrB
RG
5R B
E
GrB LW 5B 5R
RG RG LY (Not use)
B
5B
L 3R B
G YW
GR
B B WL
5R
Y YR
Fuse Stop button WBr E
RG RG B
3A RB B B
W W R
L
IGN RG IGN RG B LB
GND B GND B C.W. temp. switch L.O. pressure
+ Y + YR O switch
G GR WB Starter switch Alternator
- W - WG WG AC 3R B
+7V +7V
GB YB YB
3P-F
3P-F
3P-M
3P-M
SENSOR SENSOR 17 P1 30
RB
B
GB P2 AR YG Option
O B
RW G2 G1 3L
OG WR B
3W WB Y
B
B
B B
8P-F
8P-F
8P-M
LB
8P-M
Lb
Charge LB RG RG C.W. temp. sensor L.O. temp. C.W. level switch Tacho sensor M/g oil pressure
B switch switch
L.O. press YW YW
YW
C.W. temp. WL WL WL
Alarm O
M/G.oil p. YG YB
8P-F
8P-F
8P-M
8P-M
YG circuit YG
C.W. level unit GB
WR WR WR
L.O. temp Y Y Y
WG
G G
■ 24 V insulated ground connection without air heater (option)
L.O. filter B
G
G
Wire harness B

sensor
L.O. filter bypass valve switch
Instrument panel
(3P-M) (8P-F) (8P-M)

WIRING DIAGRAMS
Detail of connector (Arrow A-A) Insulated ground connection

016095-04EN01
51
52
L.O.P C.W. temp Tacho. with Buzzer Buzzer Illumi.
gauge gauge hour meter stop
BZ
+ - +- U +- P
RW
RG
OG
B
GrB
RG
LW
LY Relay
GrB (Not use)
RG RG L
B
GR LR LR
B Fuse
YR Stop button L
RG 3A RB WBr LY
W W A B
B
B
IGN RG
B Starter switch M P2 P1 Battery Battery
GND O
+ YR
GR WB AC 3R E Relay + - + -
- 30 LW LW
3P-F
WG
3P-M
52 ページ
+7V 17 P1
RB
SENSOR YB YB P2 AR (DC24V, 240AH)
RW G2 G1 3L
OG 3W Engine stop motor
Battery switch
RG RG RG
L.O. press Wire harness
8P-F
YW
8P-M
B
C.W. temp. WL YW YW LR
WL WL WBr B B
WIRING DIAGRAMS
M/G.oil p. YG Alarm O
circuit
C.W. level WR YG unit YG
L.O. temp. Y WR WR 5W C
Y Y Starting relay Starter
8P-F
8P-M
L.O. flter G G G 5R B
Instrument panel (Sub) E
B 5B
5R
LW
5B
L.O.P C.W. temp Tacho. with Buzzer Buzzer Illumi. LY 3R B

stop L (Not use)
Boost gauge gauge gauge hour meter YW
BZ B WL
5R
+ - + - +- U +- P
Fuse E
RW
RG
OG
B
GrB
RG
Stop button B
3A RB WBr B B
W W R
GrB L
B
RG RG LB
B L.O. pressure
C.W. temp. switch
G GR Starter switch switch Alternater
B B O
Y YR AC 3R
RG RG RW 30
3P-F
3P-F
3P-M
3P-M
OG 17 P1
RB
B
P2 AR YG
RG WB O B Option
IGN IGN RG G2 3L
GND B GND B G1 WR B
+ Y + YR 3W Y
G WB WB
- W - GR WG B
+7V GB +7V WG YB B
B
SENSOR SENSOR YB B
GB B
8P-F
8P-F
8P-M
8P-M
C.W. temp. sender L.O. temp. C.W. level sensor Tacho sensor M/G oil pressure
switch switch
LB
Lb
Charge LB RG RG
B
L.O. press YW YB
8P-F
YW
8P-F
8P-M
8P-M
YW
C.W. temp. WL WL GB
WL
Alarm O
M/G.oil p. YG WG
C.W. level YG circuit YG B
WR WR unit WR G
L.O. temp. Y Y B
Y
G G
L.O. flter G
sensor
■ 24 V insulated ground connection without air heater (tow-place gauge)
Instrument panel (Main) L.O. filter bypass valve switch

Color coding
R Red Lg Light green (3P-M) (8P-F) (8P-M)
B Black Lb Light blue Starter switch
W White Br Brown 30 AC 17 G1 G2 P1 P2 AR Detail of connector (arrow A-A)
Y Yellow P Pink GLOW
L Blue Gr Gray OFF
G Green Pu Purple ON
O Orange START
Insulated ground connection
016096-04EN00
YANMAR STANDARD MOTOR-DRIVEN BILGE PUMP (OPTION) 53
YANMAR STANDARD MOTOR-DRIVEN

BILGE PUMP (OPTION)
■ Features
• Since parts of this bilge pump that come in contact with bilge are made of polyvinyl chloride (PVC) and acid and
alkali resistant materials, you may use this pump without worrying about its wearing out.
• There is no need to worry about idling or seizure of this bilge pump because it is equipped with a protective device
which brings about an automatic stop when bilge is gone and the pump does not lift anything.
■ Method of fitting and use

• Connect the red wire to positive (+) and black wire to negative (–) respectively, avoid mis-wiring.
• Install the pump body where it can be used easily with the battery and operating switch as the pump body is con-
nected with 3 m long cord.
• Fit the strainer part of the bilge pump to the ship bottom by use of metal fittings.
Cable assembly
Motor assembly
Pump kit
OUT Vacuum
switch assembly
Filter
IN 016097-00E
Record of ownership
Take a few moments to record the information you need when you contact YANMAR for service, parts or literature.
Engine model: ______________________________________________________________________________
Engine serial No.:____________________________________________________________________________
Date purchased: _____________________________________________________________________________
Dealer: _____________________________________________________________________________________
Dealer phone: _______________________________________________________________________________

YANMAR POWER TECHNOLOGY CO., LTD.
‫ڦ‬Yanmar (Tsukaguchi)
5-3-1, Tsukaguchi-honmachi, Amagasaki
Hyogo, 661-0001, Japan
Phone: +81-6-6428-3137 Fax: +81-6-6421-5549
Overseas Office
‫ڦ‬Yanmar Europe B.V. (YEU)

Brugplein 11, 1332 BS Almere-de Vaart, Netherlands
Phone: +31-36-5493200 Fax: +31-36-5493209
‫ڦ‬Yanmar Asia (Singapore) Corporation Pte. Ltd. (YASC)
4 Tuas Lane, Singapore 638613
Phone: +65-6861-3855 Fax: +65-6862-5189
‫ڦ‬Yanmar America Corporation (YA)
101 International Parkway,
Adairsville, GA 30103, U.S.A.
Phone: +1-770-877-9894 Fax: +1-770-877-9009
‫ڦ‬Yanmar Engine (Shanghai) Co., Ltd.
Room 1101-1106, No.757 Mengzi Road,
Huangpu District, Shanghai 200023 PRC
Phone: +86-21-2312-0688 Fax: +86-21-6880-8090
‫ڦ‬Yanmar South America Industria De Maquinas Ltda (YSA)

AV. Presidente Vargas, 1400 Indaiatuba/SP
Sao Paulo, Zip Code 13338-901, BRAZIL
Phone: +55-19-3801-9224 Fax: +55-19-3875-3899, 2241
As of March 1st, 2020
OPERATION MANUAL
6AYM-WGT, 6AYM-WET, 6AYM-WST
1st edition: May 2012

2nd edition: July 2013
3rd edition: December 2017
3rd edition 1st rev.: March 2019
4th edition: April 2020
Issued by: YANMAR POWER TECHNOLOGY CO., LTD.

Edited by: YANMAR GLOBAL CS CO., LTD.
YANMAR POWER TECHNOLOGY CO., LTD.
0A6AY-EN0043
https://www.yanmar.com Apr.2020

6Aym-Wgt 6Aym-Wet 6Aym-Wst: Operation Manual

Uploaded by

Copyright:

Available Formats

6Aym-Wgt 6Aym-Wet 6Aym-Wst: Operation Manual

Uploaded by

Document Information

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

6Aym-Wgt 6Aym-Wet 6Aym-Wst: Operation Manual

Uploaded by

Copyright:

Available Formats

OPERATION MANUAL

MARINE PROPULSION ENGINE

Thank you for purchasing a YANMAR Marine Diesel Engine.

MODEL 6AYM-WGT, 6AYM-WET, 6AYM-WST

All Rights Reserved, Copyright YANMAR POWER TECHNOLOGY CO., LTD.

FUEL OIL, LUBRICATING OIL AND COOLANT …………………11

CHECKING AND SERVICING THE TURBOCHARGER …………31

TROUBLESHOOTING AND COUNTERMEASURES ……………44

FOR YOUR SAFETY 1

FOR YOUR SAFETY

DANGER indicates a hazardous situation which, if not avoided, will result

WARNING indicates a hazardous situation which, if not avoided, could

CAUTION indicates a hazardous situation which, if not avoided, could

NOTICE indicates a situation which can cause damage to the machine,

2 FOR YOUR SAFETY

Ventilation of the battery area

Fires from oil ignition

Alcohol and drugs

FOR YOUR SAFETY 3

Safety precautions for maintenance

Fires from oil ignition

Exhaust gas poisoning

4 FOR YOUR SAFETY

FOR YOUR SAFETY 5

停止後、1 0 分間は開けないで下さい。 No. Part No.

6 FOR YOUR SAFETY

No. Part No.

FOR YOUR SAFETY 7

Precautions for Lifting the Engine

For the mass, refer to Specifications in the Operation Manual.

8 FOR YOUR SAFETY

■ Location of engine nameplate:

Model Unit 6AYM-WGT 6AYM-WET 6AYM-WST

Type – Vertical, 4-cycle, turbo-charged diesel engine

Combustion system – Direct injection

Bore × stroke mm 155 × 180

Direction of rotation – Counterclockwise (Viewed from flywheel side)

Cooling system – Constant temperature cooling system (with heat exchanger)

Lubrication system – Forced lubrication with gear pump

Standard oil pan: 91

Turbocharger type – Exhaust gas turbocharger (with air cooler)

Starting system – Electric starting or air starting

Oil filler cap

Engine oil cooler

Engine oil filter

FUEL OIL, LUBRICATING OIL AND COOLANT 11

FUEL OIL, LUBRICATING OIL AND COOLANT

■ Quality criteria of fuel oil

In time of fuel supply

12 FUEL OIL, LUBRICATING OIL AND COOLANT

Flash point Kinetic viscosity mm2/s (cSt)

FUEL OIL, LUBRICATING OIL AND COOLANT 13

Water quality for coolant

■ Long Life Coolant (LLC) mixture selection

When starting a new engine, perform the following procedure.

Fuel injection pump Over flow valve

Fuel oil return pipe

Fuel priming pump

Less than Fuel tank