Westerbeke 12C- TWO User manual

SERVICE MANUAL
MARINE DIESEL ENGINES
12C-TWO 120-TWO
PUBLICATION NO. 055411
REVISION 1
JUNE 2012
J'~ rWESTERBEKE
J WESTERBEKE CORPORATION • 150 JOHN HANCOCK ROAD
J M'(LES STANDISH INDUSTRIAL PARK • TAUNTON MA 02780
WEB SITE: WWW. WESTERBEKE.COM
NMMA Member National Marine Manufacturers Association
--

A wARNING
Exhaust gasses contain Carbon Monoxide, an odorless and
colorless gas. Carbon Monoxide is poisonous and can cause
unconsciousness and death. Symptoms of Carbon Monoxide
exposure can include:
•Dizziness
• Throbbing in Temples
•Nausea
•Headache
• Muscular Twitching
• Vomiting
• Weakness and Sleepiness
• Inability to Think Coherently
IF YOU OR ANYONE ELSE EXPERIENCE ANY OF THESE SYMPTOMS,
GET OUT INTO THE FRESH AIR IMMEDIATELY. If symptoms persist,
seek medical attention. Shut down the unit and do not restart
until it has been inspected and repaired.
A WARNING DECAL is provided by
WESTERBEKE and should be fixed to a
bulkhead near your engine or generator.
WESTERBEKE also recommends installing
.... ~~~~~\ CARBON MONOXIDE DETECTORS in the
living/sleeping quarters of your vessel.
They are inexpensive and easily
L~~~~-_j obtainable at your local marine store.
CALIFORNIA
PROPOSITION 65 WARNING
Marine diesel and gasoline engine
exhaust and some of its constituents
are known to the State of California
to cause cancer, birth defects,
and other reproductive harm.

SAFETY INSTRUCTIONS
INTRODUCTION
Readthis safety manual carefully. Most accidents are
caused by failure
to follow fundamental rules and precau-
tions. Know when dangerous conditions exist and take the
necessary precautions
to protectyourself, your personnel,
and your machinery.
The following safety instructions are in compliance with
the American Boat
and Yacht Council (ABYC) standards.
PREVENT ELECTRIC SHOCK
A WARNING: Do not touch AC electrical connections
while engine is running. Lethal voltage is present at
these connections!
• Do not operate this machinery without electrical
enclosures and covers in place.
• Shut offelectrical power before accessing electrical
equipment.
• Use insulated mats whenever working on electrical
equipment.
• Make sure your clothing and skin are dry, not damp
(particularly shoes) when handling electrical equipment.
• Remove wristwatch and all jewelry when working on
electrical equipment.
• Do noit connect utility shore power to vessel's AC
circuits, except through a ship-to-shore double throw
transfer switch. Damage to vessel's AC generator may
result
if this procedure is not followed.
• Electrical shock results from handling a charged
capacitor. Discharge capacitor by shorting tenninals
together.
PREVENT BURNS - HOT ENGINE
A WARNING: Do not touch hot engine parts or
exhaust system components. A running engine gets
very hot!
• Always check the engine coolant level at the coolant
recovery tank.
A WARNING: Steam can cause injury or death!
• In case of an engine overheat, allow the engine to cool
before touching the engine or checking the coolant.
PREVENT BURNS - FIRE
A WARNING: Fire can cause injury or death!
• Prevent flash fires. Do not smoke or permit flames or
sparks to occur near the carburetor, fuel line, filter, fuel
pump, or other potential sources
of spilled fuel or fuel
vapors. Use a suitable container
to catch all fuel when
removing the fuel lines, fuel filters, or other fuel system
components ..
• Do not opeerate with a Coast Guard Approved flame
anester removed. Backfire can cause severe injury or
death.
• Do not operate with the air cleaner/silencer removed.
Backfire can cause severe injury or death.
• Do not smoke or permit flames or sparks to occur near
the fuel system. Keep the compartment and the
engine/generator clean and free
of debris to minimize the
chances
of fire. Wipe up all spilled fuel and engine oil.
• Be aware -Diesel and gasoline will bum.
PREVENT BURNS - EXPLOSION
A WARNING: Explosions from fuel vapors can cause
injury or death!
• Follow re-fueling safety instructions. Keep the vessel's
hatches closed when fueling. Open and ventilate cabin after
fueling. Check below for fumes/vapor before running the
blower. Run the blower for four minutes before starting
your engine.
• All fuel vapors are highly explosive. Use extreme care
when handling and storing fuels. Store fuel
in a
well-ventilated area away from spark-producing
equipment and out
of the reach of children.
• Do not fill the fuel tank(s) while the engine is running.
• Shut off the fuel service valve at the engine when servicing
the fuel system. Take care in catching any fuel that might
spill. DO NOT allow any smoking, open flames, or other
sources of
fire near the fuel system or engine when
servicing. Ensure proper ventilation exists when servicing
the fuel system.
• Do not alter or modify the fuel system.
• Be sure all fuel supplies have a positive shutoff valve.
• Be certain fuel line fittings are adequately tightened and
free
of leaks.
• Make sure a fire extinguisher is installed nearby and is
properly maintained. Be familiar with its proper use.
Extinguishers rated ABC by the NFPA are appropriate
for all applications encountered in this environment.

SAFETY INSTRUCTIONS
ACCIDENTAL STARTING
A WARNING: Accidental starting can cause injury
or death!
• To prevent accidental starting when servicing the
generator, remove the 8 amp fuse from the control panel.
• Disconnect the battery cables before servicing the engine/
generator. Remove the negative lead first and reconnect
it last.
• Make certain all personnel are clear of the engine before
starting.
• Make certain all covers, guards, and hatches are
re-installed before starting the engine.
BATTERY EXPLOSION
~----------------------------------------~ -4
A WARNING: Battery explosion can cause injury
or death!
• Do not smoke or allow an open flame near the battery
being serviced. Lead acid batteries emit hydrogen, a
highly explosive gas, which can be ignited by electrical
arcing or by lit tobacco products. Shut off all electrical
equipment in the vicinity to prevent electrical arcing
during servicing.
• Never connect the negative(-) battery cable to the
positive (+) connection terminal
of the starter solenoid.
Do not test the battery condition by shorting the terminals
together. Sparks could ignite battery gases or fuel vapors.
Ventilate any compartment containing batteries to prevent
accumulation
of explosive gases. To avoid sparks, do not
disturb the battery charger connections while the battery
is being charged.
• Avoid contacting the terminals with tools, etc., to prevent
bums or sparks that could cause an explosion. Remove
wristwatch, rings, and any otherjewelry before handling
the battery.
• Always tum the battery charger off before disconnecting
the battery connections. Remove the negative lead first
and reconnect it last when disconnecting the battery.
BATTERY ACID
A WARNING: Sulfuric acid in batteries can cause
severe injury or death!
• When servicing the battery or checking the electrolyte
level, wear rubber gloves, a rubber apron, and eye
protection. Batteries contain sulfuric acid, which is
destructive.
If it comes in contact with your skin, wash it
off at once with water. Acid may splash on the skin or
into the eyes inadvertently when removing electrolyte
caps.
..
II
A WARNING: Carbon monoxide (CO) is a deadly gas!
• Ensure that the exhaust system is adequate to expel gases
discharged from the engine. Check the exhaust system
regularly for leaks and make sure the exhaust manifolds
are securely attached and no warping exists. Pay close
attention to the manifold, water injection elbow, and
exhaust pipe nipple.
• Be sure the unit and its surroundings are well ventilated.
• In addition to routine inspection of the exhaust system,
install a carbon monoxide detector. Consult your boat
builder or dealer for installation
of approved detectors.
• For additional information, refer to ABYC T-22
(educational information on Carbon Monoxide).
A WARNING: Carbon monoxide (CO) is an invisible
odorless gas. Inhalation produces flu·like symptoms,
nausea or death!
• Do not use copper tubing in exhaust systems. Exhaust
sulfur causes rapid deterioration
of copper tubing
resulting in exhaust/water leakage.
• Do not install exhaust outlet where exhaust can be drawn
through portholes, vents, or air conditioners.
If the engine
exhaust discharge outlet is near the waterline. water could
enter the exhaust discharge outlet and close or restrict the
flow
of exhaust. Avoid overloading the craft.
• Although diesel engine exhaust gases are not as toxic as
exhaust fumes from gasoline engines, carbon monoxide
gas is present in diesel exhaust fumes. Some
of the
symptoms or signs
of carbon monoxide inhalation or
poisoning are:
Vomiting Muscular twitching
Dizziness Intense headache
Throbbing in temples Weakness and sleepiness
AVOID MOVING PARTS
A WARNING: Rotating parts can cause injury
or death!
• Do not service the engine while it is running. If a
situation arises in which it is absolutely necessary to
make operating adjustments, use extreme care
to avoid
touching moving parts and hot exhaust system
components.

SAFETY INSTRUCTIONS
• Do not wear loose clothing or jewelry when servicing
equipment; tie back long hair and avoid wearing loose
jackets, shirts, sleeves, rings, necklaces or bracelets that
could be caught in moving parts.
• Make sure all attaching hardware is properly tightened.
Keep protective shields and guards in their respective
places at all times.
• Do not check fluid levels or the drive belt's tension while
the engine
is operating.
• Stay clear of the drive shaft and the transmission coupling
when the engine
is running; hair and clothing can easily
be caught
in these rotating parts.
HAZARDOUS NOISE
A WARNING: High noise levels can cause hearing
loss!
• Never operate an engine without its muffler installed.
• Do not run an engine with the air intake (silencer)
removed.
• Do not run engines for long periods with their enclosures
open.
A WARNING: Do not work on machinery when you are
mentally or physically incapacitated by fatigue!
OPERATORS MANUAL
Many of the preceding safety tips and warnings are repeated
in your Operators Manual along with other cautions and
notes to highlight critical information. Read your manual
carefully, maintain your equipment, and follow all safety
procedures.
GASOLINE ENGINE AND GENERATOR INSTALLATIONS
Preparations to install a gasoline engine or generator should
begin with a thorough examination
of the American Boat and
Yacht Council's (ABYC) standards. These standards are from
a combination
of sources including the USCG and the NFPA.
Sections of the AB YC standards of particular interest are:
H-2 Ventilation
H-24 Gasoline Fuel Systems
P-1 Exhaust Systems
P-4 Inboard Engines
E-9 DC Electrical Systems
All installations must comply with the Federal Code of
Regulations (FCR).
ABYC, NFPA AND USCG PUBLICATIONS FOR
INSTALLING DIESEL ENGINES
Read the following ABYC, NFPA and USCG publications
for safety codes and standards. Follow their recommenda-
tions when installing your engine.
ABYC (American Boat and Yacht Council)
"Safety Standards for Small Craft"
Order from:
ABYC
3069 Solomon's Island Rd.
Edgewater,
MD 21037
NFPA (National Fire Protection Association)
"Fire Protection Standard for Motor Craft"
Order from:
NFPA
11 Tracy Drive
Avon Industrial Park
Avon, MA 02322
USCG (United States Coast Guard)
"USCG 33CFR183"
Order from:
U.S. Government Printing Office
Washington, D.C. 20404
Engines & Generators
iii

TABLE OF CONTENTS
INTRODUCTION
Serial Number ..........................................................2
Siphon Break
TESTING FOR OVERHAUL ........................................... 3
Disassembly
Assembly
ENGINE TROUBLESHOOTING (Charts) ................... A-7
ENGINE DISASSEMBLY, INSPECTION
AND ASSEMBLY
DISASSEMBLY PROCEDURES ..................................... 8
CYLINDER HEAD REMOVAL ........................................ 9
CYLINDER HEAD ....................................................... 10
Cylinder Head Inspection
Valve Guide Replacement
Valve Seat Repair
Installing the Cylinder Head
Bolt Tightening Sequence
VALVE AND VALVE SPRING INSPECTION ................. 11
Valve Removal
Valve Inspection
VALVE INSTALLATIONNALVE CLEARANCE ............... 12
Torquing the Cylinder Head Bolts
VALVE CLEARANCE ................................................... 12
VALVE ADJUSTMENT/INJECTION TIMING ................ 13
Timing Adjustment
GEAR CASE/GOVERNOR ............................................ 14
Front Oil Seal Replacement
Governor Shaft/Disassembly Inspection
Installing the Governor Shaft
TIMING GEAR/CAMSHAFT ........................................ 15
Removing the Timing Gears
Timing Gear Inspection
Valve Camshaft Removal
Injection Pump Camshaft Removal
CAMSHAFT/PISTONS
AND CONNECTING RODS .......................................... 16
Inspecting the Camshaft
Installing the Camshaft/Gears
Piston and Connecting Rod Disassembly
PISTON AND CONNECTING ROD ......................... 17-18
Inspection
Piston Ring End Gap
Piston Ring Side Clearance
Installation
Installing the Piston Rings
Installing the Piston and Connecting Rod
CRANKSHAFT ............................................................ 19
Removal/Inspection
Rear Oil Seal Replacement
Inspecting the Oil Clearance
Installing the Crankshaft
CYLINDER BLOCK ..................................................... 20
Inspection
Bore Dimensions
Cylinder Reboring
ENGINE ASSEMBLY .............................................. 21-22
TORQUE SPECIFICATIONS ........................................ 23
GOVERNOR SYSTEM ........................................... 24-25
Disassembly/Inspection
Installation
EXHAUST MANIFOLD/HEAT EXCHANGER ................. 26
FUEL INJECTION PUMP ............................................ 27
FUEL INJECTORS ................................................. 28-29
GLOW PLUGS ........ .- ................................................... 30
Fuel Lift Pump
Inlet Fuel Filter
TACHOMETER ............................................................ 31
ENGINE ADJUSTMENTS ....................................... 32-34
Measuring Compression
Belt Adjustment
Testing Oil Pressure
Adjusting Idle Speed
Fuel Run/Shut-Off Solenoid
RAW WATER PUMPS .......................................... 35-36
ATLERNATOR TESTING ........................................ 37-38
STARTER MOTOR TESTING ................................. 39-42
TRANSMISSION ...................................................... .43
ENGINE SPECIFICATIONS ......................................... .44
WIRING DIAGRAMS ............................................ .45-46
SERVICE DATA/STANDARDS LIMITS .................. .47-48
STANDARD HARDWARE TORQUES .......................... .49
REMOTE OIL FILTER ................................................. 50
METRIC CONVERSION DATA............................... 51
Engines & Generators
1

INTRODUCTION
SERIAL NUMBER LOCATION
The engine's model number and serial number are located on
a nameplate mounted on the side
of the engine's manifold.
the engine's serial number can also
be found stamped ihto
the engine block on the flat surface
of the block just above
and inboard
of the injection pump. Take the time to enter this
information on the illustration
of the nameplate shown below,
as this will provide
aquick reference when seeking technical
information and/or ordering repair parts.
• MODEL SPEC MA USA SER.NO. •
.Fill in the infonnation for your reference. ~
NOTES, CAUTIONS AND WARNINGS
As this manual takes you through the disassembly, inspection
and assembly procedure
of your engine/generator, critical
information will be highlighted by NOTES, CAUTIONS,
and WARNINGS. An explanation follows:
NOTE: An operating procedure essential to note.
A CAUTION: Procedures
1
which if not strictly
observed
1
can result in the damage or destruction of
your engine/generator.
A WARNING: Procedures~ which if not properly
followed
1
can result in personal injury or loss of life.
ORDERING PARTS
·Whenever replacement parts are needed, always provide the
generator model number, engine serial number, and generator
serial number as they appear on the silver and black
name-plate located on the generator end. You must provide
us with this information so we may properly identify
your engine/generator. In addition, include a complete part
description and part number for each part needed (see
the separately furnished Parts List). Also insist upon
WESTERBEKE packaged parts because willfit or generic
parts are frequently not made to the same specifications
as original equipment.
2
RAW WATER COOLING CIRCUIT
Siphon-Break
For installations where the water injected exhaust elbow is
close
to or will be below the vessels waterline, provisions
must be made to install a siphon-break in the raw water
supply hose to the water injected exhaustelbow. The siphon-
break provides
an air vent in the raw water cooling system to
prevent raw water from filling the exhaust system and the
engine's cylinders when the engine
is shutdown.
If you have any doubt about the position of the water-
injected exhaust elbow relative to the vessels waterline under
the vessels various operating conditions,
install a siphon-
break. This precaution is necessary to protect your engine.
The siphon-break must be installed in the highest point of a
hose that is looped a minimum
of 20 inches (51cm) above
the vessels waterline. Tiris siphon-break
must always be
above the waterline during all angles of vessel operation to
prevent siphoning.
NOTE: A siphon-break requires periodic inspection and
cleaning to ensure proper operation. Failure to properly
maintain a siplwn-break can result in catastrophic engine
damage. Consult the siphon-break rnanufacturerf<>r proper
maintenance.
SIPHON-BREAK WITH STAINLESS
LOOP FOR 1" HOSE
PART N0.044010
ENGINE OVERHAUL
The following sections contain detailed information
relating to the proper operation characteristics
of the major
components and systems
of the engine. Included are
disassembly, inspection and reassembly instructions for the
guidance of suitable equipped and staffed mmine engine
service and rebuilding facilities. The necessary procedures
should be taken only by such facilities.
Additional detailed information and specifications are pro-
vided in other sections
of this manual, covering the
generator, alternator, starter motor, engine adjustments,
cooling pumps, etc.

TESTING FOR OVERHAUL
HOW TO DETERMINE ENGINE OVERHAUL PERIOD
Cause of Low Compression
Generally, the time at which an engine should be overhauled
is determined
by various conditions such as lowered engine
power output, decreased compression pressure, and increased
fuel and oil consumption. The lowered engine power output
is not necessarily due to trouble with the engine itself, but is
sometimes caused by injector nozzle wear or injection pump
wear. The decrease in compression pressure is caused by
many factors.
It is, therefore, necessary to determine a cause
or causes on the basis of data produced by periodic
inspection and maintenance. Oil analysis on a seasonal basis
is a good means
of monitoring engine internal wear. When
caused by worn cylinders
or piston rings, the following
symptoms will occur:
1 Low engine power output
2 Increased fuel consumption
3 Increased oil consumption
4 Hard engine starting
5 Noisy engine operation
These symptoms often appear together. Symptoms 2 and 4
can result also from excessive fuel injection, improper injec-
tion timing, and wear
of the injectors. They are caused also
by defective electrical devices such as the battery, alternator,
starter and glow plugs. Therefore it is desirable to judge the
optimum engine overhaul time by the lowered compression
pressure caused by worn cylinders and pistons plus increased
oil consumption. Satisfactory combustion is obtained only
under sufficient compression pressure.
If an engine lacks
compression pressure, incomplete combustion
of fuel will
take place even
if other parts of the engine are operating
properly. To determine the period
of engine overhaul, it is
important.to measure the engine compression pressure regu-
larly. At the same time, the engine speed at which the mea-
surement
of compression pressure is made should be checked
because the compression pressure varies with engine rpm.
The engine rpm can be measured at the front end of the
crankshaft.
NOTE: In case of severe vibrations and detonation noise, the
cause may be
fu~l injectorproblems, see FUEL INJECTORS.
Poolfuel quality, contaminates and loss
of positivefuel
pressure to the injection pump will result
in injectorfaults.
NOTE: Make certain the engines valve clearances are
properly adjusted.
An incorrect valve clearance can cause
symptons that might, incorrectly, suggest an engine overhaul
(cylinder misfire, white smoke, noise, etc).
OVERHAUL CONDITIONS
Compression pressure tends to increase a little in a new
engine until piston rings and valve seats have been broken in.
Thereafter, it decreases gradually with the progress
of wear of
these parts.
When decrease
of compression pressure reaches the repair
limit, the engine must be overhauled.
The engine requires overhaul when oil consumption is high,
blowby evident, and compression values are at minimum or
below. Engine compression should be 28 kg/cm2, 398psi at
280 rpm. The maximum difference between cylinders must not
exceed 10%.
Minimum compression of 355 psi (25 kg/cm2) is an indication
for overhaul.
NOTE: For Testing Compression Pressure and Oil Pressure,
refer to the Table
of Contents.
DISASSEMBLY
NOTE: Before disassembly and cleaning, carefully check
for defects which cannot befound after disassembly and
cleaning.
• All disassembled parts should be carefully arranged in
order
of reassembly. Mark or label the parts as needed
to insure proper mating and reassembly in the proper
directions and positions.
• If the disassembly procedure is complex requiring many
parts to be disassembled, the parts should be disassembled
in a way that will allow them to be efficiently reassembled
without any change in the engine's external appearance or
its performance.
• Do not remove or disassemble the parts that require no
disassembly.
• Carefully inspect each part after its removal for damage,
deformation, and other problems.
• Carefully check gaskets, packings and oil seals, even if
checking is not specified. Replace with new ones if defective.
• Be careful not to damage the disassembled parts. Keep the
parts clean.
• Use proper tools. Apply oil when necessary. Take special
care to keep the fuel system parts free from the intrusion
of dust and dirt.
ASSEMBLY
1. Wash all parts, except for oil seals, 0-rings, rubber sheets,
etc., with cleaning solvent and dry them with pressure
air.
2. Always use tools that are in good condition and be sure
you understand how to use them before performing any
job.
3. Use only good quality lubricants. Be sure to apply a coat
of oil, grease or sealant to parts as specified ..
4. Be sure to use a torque wrench to tighten parts for which
torques are specified.
Engines &Generators
3

ENGINE TROUBLESHOOTING
The following troubleshooting chart describes certain
problems relating to engine service, the probable causes
of
these problems, and the recommendations to overcome
these problems.This chart may be
of assistance in
determining the need for an engine overhaul.
PROBLEM PROBABLE CAUSE
HARD STARTING LOW CRANKING SPEED
1. Engine oil viscosity too high.
2. Run-down battery.
3. Worn battery.
4. Battery terminals loosely connected.
5. Defective starter.
DEFECTIVE INJECTION SYSTEM
1. Air trapped in fuel passage.
2. Clogged fuel filter.
3. Low injeCtion pressure.
4. Inadequate spray.
5. Injection pump delivering insufficient fuel.
6. Injection too early.
MAIN ENGINE TROUBLES
1. Low compression.
a. Incorrect valve clearance.
b. Inadequate contact of valve seat.
c. Valve stem seized.
d. Broken valve spring.
NOTE: The engine~ electrical system is protected by a 20-
ampere manual reset circuit breaker. The preheat solenoid is
mountedon the same bracket.
VERIFICATION/REMEDY
1. Replace engine oil with less viscous oil.
2. Recharge battery.
3. Replace battery.
4. Clean terminals and correct cables.
5. Repair or replace starter.
1. Bleed air from fuel system.
2. Clean or replace filter.
3. Adjust injection pressure.
4. Clean or replace noule.
5. Repair or replace injection pump.
6. Adjust injection timing.
a. Adjust valve clearance.
b. Lap valve.
c. Replace valve and valve guide.
d. Replace valve spring.
e. Compression leaks through cylinder head gasket. e. Replace gasket.
f. Piston ring seized.
f. Replace piston and piston ring.
g. Worn piston ring and cylinder. g. Overhaul engine.
2. Burnt glow plug.
2. Replace glow plug.
3. Faulty glow plug operation.
3. Check preheat circuit.
4. Incorrect governor lever position.
4. Set lever to starting position.
5. Governor spring out of POSITION
5. Correct spring
LOW OUTPUT
LOW COMPRESSION
See HARD STARTING
INJECTION SYSTEM OUT OF ADJUSTMENT
1. Incorrect injection timing.
1. Adjust injection timing.
2. Insufficient injection.
2. Repair or replace injection pump.
3. Low injection pressure.
3. Check injection noule and adjust pressure.
INSUFFICIENT FUEL
1. Air trapped in fuel system.
1. Check and retighten connector.
2. Clogged filter.
2. Clean or replace filter.
3. Contaminated fuel tank.
3. Clean tank.
INSUFFICIENT INTAKE AIR
1. Clogged air cleaner. 1. Clean or replace air cleaner.
(continued)
Engines & Generators
4

ENGINE TROUBLESHOOTING
PROBLEM PROBABLE CAUSE VERI Fl CAT I0 N/REM EDY
LOW OUTPUT (cont .. ) OVERHEATING
1. Low coolant level.
1. Add coolant.
2. Loose V-belt. 2. Adjust or replace V-belt.
3. Incorrect injection timing. 3. Adjust injection timing.
4. Low engine oil level. 6. Add engine oil.
EXCESSIVE OIL
OIL LEAKAGE
CONSUMPTION
1. Defective oil seals.
1. Replace oil seals.
2. Broken gear case gasket.
2. Replace gasket.
3. Loose gear case attaching bolts. 3. Retighten bolts.
4. Loose drain plug. 4. Retighten plug.
5. Broken rocker cever gasket. 5. Replace gasket.
6. Loose rocker cover attaching bolts. 6. Retighten attaching bolts.
OIL LEVEL RISING
1. Leaking injection pump.
1. Repair pump plungers.
2. Bent or twisted connecting rod.
2. Replace connecting rod.
3. Worn piston ring.
3. Replace ring.
4. Worn piston or cylinder. 4. Replace piston and rebore cylinder.
OIL LEVEL FALLING
1. Defective stem seal.
1. Replace stem seal.
2. Worn valve and valve guide.
4. Replace a valve and valve guide.
EXCESSIVE FUEL
ENGINE BODY TROUBLES
CONSUMPTION
1. Noisy knocking.
1. See KNOCKING.
2. Smoky exhaust.
2. See SMOKY EXHAUST
3. Moving parts nearly seized or excessively worn.
3. Repair or replace.
4. Poor compression.
4. See LOW COMPRESSION; HARD STARTING.
5. Improper valve timing.
5. Adjust.
6. Improper valve clearance.
6. Adjust.
INSUFFICIENT INTAKE AIR
1. Air intake obstructed.
1. Remove obstruction.
NOZZLE TROU3LES
1. Seized nozzle.
1. Replace.
2. Worn nozzle.
2. Replace.
IMPROPER FUEL
Replace with proper fuel (Cetane #45 or better).
FUEL LEAKS
Find fuel leaks.
SMOKY EXHAUST
WHITISH OR PURPLISH
1. Excessive engine oil.
1. Correct oil level.
2. Excessive rise of oil into combustion chamber.
a. Poor piston contact. a. Check.
b. Seized piston ring.
b. Replace or clean.
c. Excessive piston-to-cylinder clearance. c. Replace or correct.
(continued)
5

ENGINE TROUBLESHOOTING
PROBLEM
PROBABLE CAUSE
VERIFICATION/REMEDY
SMOKY EXHAUST (cont.
1
WHITISH OR PURPLISH (cont.
d. Worn valve stem and valve guide.
d. Replace.
e. Low engine oil viscosity.
e. Replace.
f. Excessive oil pressure.
f. Correct.
3. Injection timing is too late. 3. Adjust.
4. Insufficient compression.
4. See LOW COMPRESSION; HARD STARTING.
BLACKISH OR DARK GRAYISH
1. Engine body troubles.
a. Poor compression.
a. See LOW COMPRESSION; HARD STARTING.
b. Improper valve clearance. b. Adjust.
2. Insufficient intake air (air cleaner clogged).
2. Clean air cleaner.
3. Improper fuel.
3. Replace with proper fuel.
ABNORMAL SOUND
CRANKSHAFT AND MAIN BEARING
OR NOISE
1. Badly worn bearing. 1. Replace bearing and grind crankshaft.
2. Badly worn crankshaft.
2. Grind crankshaft.
3. Melted bearing. 3. Replace bearing and check lubrication system.
CONNECTING ROD AND CONNECTING ROD BEARING
1. Worn connecting rod big end bearing. 1. Replace bearing.
2. Worn crankpin. 2. Grind crankshaft.
3. Bent connecting rod. 3. Correct bend or replace.
PISTON, PISTON PIN, AND PISTON RING
1. Worn cylinder. 1. Rebore cylinder to oversize and replace piston.
2. Worn piston pin. 2. Replace piston.
3. Piston seized.
3. Replace piston and rebore cylinder.
4. Piston seized and ring worn or damaged. 4. Replace piston and rings.
VALVE MECHANISM
1. Worn camshaft.
1. Replace.
2. Excessive valve clearance. 2. Adjust.
3. Worn timing gear. 3. Replace.
4. Worn fan pulley bearing. 4. Replace.
ROUGH OPERATION
INJECTION PUMP SYSTEM
1. Uneven injection. 1. Adjust injection or replace parts.
2. Control rack malfunctioning. 2. Disassemble, check and correct injection pump.
3. Worn delivery valve.
3. Replace.
4. Inadequate injection nozzle spray. 4. Replace injection nozzle.
GOVERNING SYSTEM
1. Governor lever malfunctioning.
1. Check governor shaft and correct operation.
2. Fatigued governor spring. 2. Replace.
(continued)
6

ENGINE TROUBLESHOOTING
PROBLEM
PROBABLE CAUSE
KNOCKING ENGINE KNOCKS WITHOUT MUCH SMOKE
!
1. Main engine troubles.
a. Overheated cylinder.
'
b. Carbon deposits in cylinder.
I
2. Too early injection timing.
I
3. Too high injection pressure.
I
I
4. Improper fuel.
KNOCKING WITH DARK SMOKE
1. Poor compression.
2. Injection pump malfunctioning.
a. Worn plunger.
b. Pinion is not in mesh with control rack.
c. Broken delivery valve spring.
d. Worn delivery valve seat.
3. Improper nozzle.
a. Poor spray.
b. Poor chattering.
c. After-injection drip.
d. Nozzle needle valve seized.
INTERMITTENT
1. Fuel filter clogged.
EXHAUST SOUND
2. Fuel pipe sucks air.
3. Water mixed in fuel
OVERHEATING
1. V-belt slackening or slippery with oil.
2. Damaged water pump.
3. Lack of coolant.
4. Low oil level or poor oil quality.
5. Knocking.
6. Moving parts seized or damaged.
7. Defective thermostat.
LOW OIL PRESSURE
1. Worn Bearings.
2. Relief valve malfunction.
3. Clogged oil cooler.
4. Diesel dilution of the oil.
NOTE: Refer to the Table of Contents for testing and adjustment
procedures
for the following:
Valve Clearance
Injection Timing
Oil Pressure
Engine Compression
7
VERIFICATION/REMEDY
a. See OVERHEATING; LOW OUTPUT.
b. Clean.
2. Correct.
3. Correct.
4. Replace with proper fuel.
1. See LOW COMPRESSION; HARD STARTING.
a. Replace.
b. Correct.
c. Replace.
d. Replace.
a. Clean or replace nozzle.
b. Repair or replace nozzle.
c. Repair or replace nozzle.
d. Replace.
1. Clean or replace.
2. Retighten pipe joints or replace pipe.
3. Replace fuel.
1. Adjust, replace or clean.
2. Replace.
3. Add.
4. Add or change.
5. See KNOCKING.
6. Replace.
7. Replace.
1. Engine overhaul replace bearings.
2. Overhaul oil pump.
3. Repair.
4. Injection pump repair.

DISASSEMBLY PROCEDURES
REMOVE EXTERIOR COMPONENTS
Unplug the instrument panel wiring harness. Drain the trans-
mission fluid and unbolt the transmission.
NOTE: Label any lines, hoses or cables as you separate them.
Refer to the Table of Contents for information on
Transmissions.
1. Remove the start motor, drive belt, and the alternator.
Label the wires
and cables.
2. With the hoses disconnected, remove the thermostat
housing
and housing gasket, leaving the temperature
sender.
3. Remove the bell housing
and the circuit breaker
pre-heat solenoid bracket.
4. Remove the engine
back plate.
5. Remove the oil filter, oil hoses
and mounting bracket.
Make note
of the hose arrangements.
6. Remove the transmission
damper plate from the
engine flywheel.
7. Remove the engine mounted
raw water pump,
complete with its
adapter mounting plate. See RAW
WATER PUMP for parts breakdown.
8. Remove the engine
heat exchanger. If possible, leave
one end
of each hose connected to the part being
removed.
LABa THE WIRES
The engine should be securely mounted on a
suitable engine stand.
TRANSMISSION
DAMPER PLATE
8
9. Remove the exhaust components from the exhaust
manifold
a) Remove the exhaust elbow (ifapplicable) from the
lower surface
of the manifold. Clean and inspect for
cracks
and defects. Replace as needed.
b) Remove the exhaust nipples, elbows
and plugs from
the manifold.
c) Remove the water connectors from the ends of the
manifold. Be sure to note the proper location
and
arrangement of each for properalignment.
d) Examine all
parts for defects, corrosion and wear
and replace as needed.
e) Flush out the coolant recovery tank and clear its hose
passage. Set aside to re-install on the boat.
10. Remove the coolant circulating pump. Refer to
COOLANTPUMP ASSEMBLY.
11. Remove the air intake silencer and the intake
manifold.
12.
Prepare to disassemble the main engine.
WHEN REMOVING
THE MOUNTING BOLTS,
LOCK THE FLYWHEEL
WITH A RING GEAR
BREAK TOOL
TAB WASHER

CYLINDER HEAD REMOVAL
1. Remove the engine heat exchanger. If possible, leave one
end of each hose connection attached to the part being
removed. For maintenance, see HEAT EXCHANGER.
2. Remove the starter motor. For starter motor repair, see
STARTER MOTOR
3. Remove the flywheel.
4. Remove the engine backing plate.
5. Unbolt elbows at head and remove the exhaust manifold
in its entirety. See EXHAUST MANIFOLD.
6. Remove the engine alternator and raw water pump.
7. Remove the engine mounted fuel filter and fuel line to
injection pump. (Note the arrangement of sealing wash-
ers on banjo bolts at fuel filter and injection pump.)
8. Remove the thermostat housing and the thermostat.
Leave temperature sending unit in place.
9. Remove the coolant circulating pump.
10. Remove the air intake silencer.
INTAKE MANIFOLD
Now the basic engine is ready for disassembly, cleaning, and
repair ifnecessary.
1. Remove the high pressure injector line assembly. When
disconnecting each injector line from the injection pump
side delivery valve holder, grasp the holder with a wrench
to prevent it from loosening. After removing the pipe
assembly, plug the nozzle holders and delivery valve
holders to prevent intrusion
of dust.
2. Disconnect the glow plug lead wire.
3. Loosen the fresh water pump drive belt and dismount the
belt, idler pulley and bracket.
4. Disconnect the air breather hose.
CYLINDER HEAD REMOVAL
5. Remove the rocker cover.
6. Remove the rocker shaft assembly.
7. Loosen the cylinder head mounting bolts equally and
gradually in the numerical order as illustrated and remove
the cylinder head assembly (including the exhaust mani-
fold).
9
SEQUENCE FOR LOOSENING CYUNDER HEAD BOLTS
SUB !JOLTS
FRONT~
8. Lift the cylinder head off the engine.
9. Remove the cylinder head gasket. Clean the cylinder
head and the cylinder block surface from which the gas-
ket has been removed.
10. Remove the injector assemblies and glow plugs from the
cylinder head.
11. Remove the exhaust manifold from the cylinder head.
12. Remove the valve retainers, valve springs and valves
from the cylinder head. When removing each valve
retainer, depress the retainer against the valve spring and
remove the retainer lock. Identify each valve by putting a
mark indicating the number
of the cylinder from which
the valve
is removed. ~CAP
13. Remove the valve stem seal. s __ · ~
~ '.\:,YJ D-RING
HOSE~ I
NIPPLE-----/
ROCKER COVER
GASKET
VALVE SPRING RETAINER
CYLINDER
HEAD
GASKET

CYLINDER HEAD
Cylinder Head Inspection
Clean the cylinder and the cylinder block surface from which
the gasket has been removed. Carefully check the cylinder
head for cracks or
any other damage as shown below. Use a
straightedge and a thickness gauge to check the surface for
distortion and warpage.
Check the valve guides and valve contact surfaces.
Cylinder head distortion repair limit: 0.004 in {0.1 mm)
Valve Seat Repair
If a valve seat is found defective, reface it or have a machine
shop install a new seat.
Sinkage of valve
Standard 0.019in (0.5mm)
Limit 0.059in (1.5mm)
NOTE: When checking valve sinkage, the valve guide must be
in normal condition. Resurface the valve seat so that it con-
tacts the mid-ponion
ofthe valveface.
Check guides for
wear and damage.
/
VALVE SINKAGE
Check valve contact, wear,
damage and the sink of the seat face.
Valve Guide Replacement
Check for cracks; damage
and water leaks. Remove all
oil,
sludge, sealant
and carbon deposits.
If a valve guide is found defective, replace it.
1. Remove the valve guide by pressing at its upper end and
pull it out to the valve seat side.
2. Install the valve guide by press fitting the guide from the
upper side of the cylinder head to a height of 14mm
(±0.5) from the valve spring seat face.
D.25mm-~-f
(0.984 in)
0.12 mm
(0.472 in)
....,.l:--+-- 6.6 :1:0.015 mm
(0.295 in)
PRESS-ATTING THE VALVE GUIDE
so·
\
RESURFACING THE VALVE SEAT
(INTAKE AND EXHAUST)
Installing The Cylinder Head
f'Width of Valve Contact
, 1.3-1.8mm
/', ',
Installation of the cylinder head is in the reverse order of
removal. Pay attention to the following.
1. Renew the cylinder head gasket. No application of
sealant is necessary. On the upper front of the gasket is
the engine model to which the gasket is applicable. Be
careful not to confuse it with a gasket for another engine
model.
2; Tighten the cylinder head bolts in the numerical order
shown going through that order two or three times.
Tighten each bolt a little at a time
untiJ. all are tightened
to the specified torque.
CYUNDER HEAD BOLT TIGHTENING SEQUENCE
FRONT
I'WIWESTERBEKE
lEngines & Generators
10

VALVE AND VALVE SPRING INSPECTION
VALVE REMOVAL
1. Dismount the cylinder head assembly.
2. Depress the valve retainer (to compress the valve spring)
and remove the retainer lock.
REMOVING VALVES
3. Remove the valve.
4. Inspect all the components and repair or replace any
defective parts.
SQUARENESS CHECK ---'~
SQUARENESS GAUGE
Squareness Check
Standard 2•
Limit 3•
Valve Spring Squareness Check. Check the squareness of
the valve spring and, if it is more than the limit, replace the
spring
..
Valve Spring Fitting Pressure Check. Check the valve
spring fitting pressure with a valve spring tester and, if the
pressure is less than the limit, replace the spring.
Pressure (load) Test
Standard 13.0951bs/1.398in (5.94 kg/35.5 mm)
limit -15%
NOTE: Measure the fitting pressure after compressing the
spring several times.
Valve
Spring Free Length Check. Measure the free length
of the valve spring and if the free length is less than the limit,
replace it.
VAlVE SPRING TESTER
Free length Test
Standard 1.595 in (40.5 mm)
limit 1.5 in (39.3 mm)
Valve Inspection
Valve Stem Wear Inspection. If the valve stem is bent or its
diameter is less than the standard, replace the valve.
Valve Stem
Standard
Margin
Standard
limit
6.6 mm (0.260 in)
1.0 mm (0.039 in)
0.5 mm (0.019 in)
1. If the valve face is found .worn down. resurface it with a
valve refacer.
If the margin of the resurfaced valve
exceeds the service limit, replace the valve.
2. If the valve stem end has been indented
by wear. flatten it
with an oil stone.
·---:r--
45. }/C:::::;:::::=:::::=::::::l:=l=-=
/
INSPECTING VALVES
WESTERBEKE
Engines & Generators
11

VALVE INSTALLATION /VALVE ADJUSTMENT /INJECTION TIMING
Installation
Install the valve and valve springs. Refer to the illustrations
and callouts shown below.
NOTE: Be careful not to damage the spring and stem seal by
excessively compressing the spring when installing the valve
spring.
Mount the Cylinder Head Assembly and adjust the valve
clearances.
D.375in
· (14.Bmm)
Witlllhe retainer-- 0
depresud to compress
lhe spring,. instaU lhe
retainer lock.
INSTALLING SPRING
INSTAlliNG THE
SPRING RETAINER
TORQUING THE CYLINDER HEAD BOLTS
NOTE: Cylinder head bolts must be retightened before adjust-
ing the valve clearances.
Tighten the cylinder head bolts according to the the sequence
shown. Make sure the engine is cold when this is done.
Before applying the specified torque to the bolt, loosen it
1/4
to 1/2 of a turn and then apply the torque. Follow this proce-
dure according to the numbered sequence shown in the illus-
tration.
TORQUE SPECIFICATIONS:
Bolts 11, #2 ·14.4 • 21.71b·fl (2.0 • 3.0 Kg-m)
Bolts #3; #4, #5, 116, 111, 118, • 54;2 • 61.41b-ft (7 .5 • 8.5 Kg~m)
ROCKER SHAFT HOLD-DOWN BOLTS:
All main bolts are 14mm across the bolt head flats.
All sub bolts are
12mm across the bolt head flats.
Rocker shaft hold-down bolts are
12mm across the bolt
head flats.
Rocker Cover Hold Down Cap Nuts- (lOmm socket) (snug)
CYUNDER HEAD BOLT TIGHTENING SEQUENCE
FRONT~.
SUB BOLTS
NOTE: The RockerAssembly (Rocker Arms, Shaft and Stays)
are not
in the engine when the cylinder head bolts are retight-
ened
in tliis procedure.
VALVE CLEARANCE
Firing Order: 1·2
NOTE: Removal of the engine's glow plugs will allow for
easier rotation of the engine's crankshaft.
1. Set the piston in the cylinder to be adjusted at Top Dead
Center (T.D.C.) of the the compression stroke. Valve
clearance: 0.010 in (0.25 nun) cold for both intake and
exhaust valves.
2. Rotate the crankshaft observing the movement
of the
valves
for cylinder #1 and place the piston at Top Dead
Center
of its compression stroke. To confirm this, the
TDC timing mark on the front crank shaft pulley should
be in alignment with the timing mark on the front gear
case.
3. Adjust the Intake and Exhaust valves for cylinder #1..
4. Rotate the engine crankshaft 180 degrees in the normal
direction
of rotation and adjust the valves for cylinder #2.
Engines & Generators
12

VALVE ADJUSTMENT /INJECTION TIMING
19°
CRANKSHAFT
PUllEY
TIMING MARKS
TIMING POINTER
Injection Pump Timing Adjustment (Spill Timing)
If your engine's fuel injection timing is not properly adjusted,
the engine will not operate properly, and may be difficult to
start. Have the injection pump delivery rate checked by a
well-established fuel injection
shop. Adjust the injection as
follows:
NOTE: The injection pumpfuel rack needs to be in the full
fuel delivery position when perfonning this spill
timing. To
do this, unscrew the fuel shut off solenoid and remove the
side cover to expose the injection pumpfuel rack. Manually
move
the fuel rack to the full fuel delivery position (move
fully to the left) secure it in this position then proceed.
1. Remove the high pressure fuel line from between the
No. 1injector and the No. 1 fuel delivery valve holder.
2. Remove the No. 1 fuel delivery valve holder over
"0" ring and remove the delivery xalve spring beneath
the holder.
3. Reinstall only the delivery valve holder and reattach the
high pressure fuel line to the delivery holder. Attach it so
that the end that would connect to the fuel injector is
pointing away from the engine fuel will flow from this
line during the timirig check.
Rotate the.engine's crankshaft in its normal direction of
rotation
to position piston No. 1at the beginning of itS
compression stroke.
Move the throttle lever to its full open position and operate
the electric lift pump. Slowly rotate the crankshaft clockwise
(as viewed from the front), catching the fuel from the No. 1
fuel line, until the instant the fuel completely stops flowing
(no drips). At this instant, the(19" BTDC)timing mark on the
crankshaft pulley should be directly aligned with
the timing
indicator on the front ofthe gear case ± .5 degrees.
If the specified injection timing ( 19" BTDC) cannot be
attained, adjust the timing by increasing or decreasing the
thickness ofshim material under the injection pump's
mounting
flange to change the injection timing point.
Changing the shim thickness by 0.004 inch (0.01mm)
changes the injection timing by approximately one degree.
To advance the timing, decrease the shim thickness, as
required. To retard the timing, increase the shim thickness, as.
required. Refer to your Parts List for shim part
numbers.
13
FUEL INJECTION PUMP
PlUNGER

GEAR CASE I GOVERNOR
GEAR CASE ASSEMBLY
1. Remove the drive belt and the crankshaft pulley.
2. Remove the alternator.
3. Remove the water pump assembly.
GASKET
WATER PUMP
ASSEMBLY
SHEAVE --.. ·~ •1 ~ .
For pump breakdown,
see COOLANT
CIRCULAnNG PUMP.
~- ~'-~1/JJff>..~.....-
4. Remove the tie-rod cover from ffie side of the injection
pump.
5. Being careful not to let the spring fall into the case,
remove the tie-rod and the tie-rod spring.
6. Remove the governor case cover.
7. Remove the gear case assembly.
8. Inspect the disassembled parts. Replace parts worn
beyond standard and service limits.
wear.
and damage.
Check Plunger
Assembly for wear
and smooth
L------------- movement.
Front Oil Seal Replacement
Check springs
tor fatigue.
Check BRACKETS
for bends and
twists.
'W'~ l~~
Check SHAFT,........- ~ ':1 /~Check SLIDING SLEEVE
for flaws.
1 joint
for wear and
damage.
Governor Shaft Disassembly/Inspection
NOTE: For additional information refer to the GOVERNOR
SYSTEM section.
1. Taking care to not scratch the gear case, remove the
expansion plug. \
2. Remove the grooved pin.
3. Draw out the shaft and the two bushings.
FLUSH WITH
THIS PLANE
PRESS·Fm'ING THE
GOVERNOR SHAFT BUSHING
Press-fit two new bushings into place as illustrated.
EXPANSION
PLUG
GROOVED PIN
INSTAWNG THE GOVERNOR SHAFT
5. Check the governor parts for wear, damage, and fatigue.
If any parts are defective, repair orreplace them.
Installing the Governor Shaft
Install the governor shaft in the reverse order of removal then
press-fit the expansion plug into the shaft hole in the gear
Remove and replace the front oil seal. Apply a thin coat of case.
engine oil to the circumference and the lip of the new seal
before press-fitting it to the gear case cover.
14
0-- TAPER PLUG
Torque 10.8 ·15.9H·Ib (1.5- 2.2m-kg)
OIL PUMP
Torque 5.8 -7 .OH-Ib
(0.8 - 1.0m-kg)

TIMING GEAR I CAMSHAFT
REMOVING THE TIMING GEARS
1. Remove the snap ring and disassemble the idler gear.
2. Remove the valve camshaft and the injection pump
camshaft on which the gears are press-fitted, remove the
gears.
3. Remove the crankshaft. Remove the crankshaft gear.
-
.-
Timing Gear Inspection
TIMING
GEAR
CASE
Inspect all gear teelli tor wear and
damage. If any gear is defective,
replace the gear.
Carefully inspect the gears, gear teeth and gear bushings.
Check the clearance between the idler gear bushing and its
shaft.
Idler Gear Bushing Clearance
standard 0.03- 0.07mm (0.001 - 0.010in)
Limit 0.2mm (O.OOSin)
When assembled, check the backlash between the two gears
in mesh. Idler gear to crankshaft, injection pump to idler, and
camshaft to idler.
Backlash Between Gears
Standard 0.01 • 0.14mm (0.0003- 0.005in)
0.3mm (0.012in)
15
Installation
Press-fit the crankshaft gear onto the crankshaft.
Press-fit the valve camshaft gear and the ignition pump
camshaft gear onto their respective shafts.
Install the gear assemblies
in the following sequence.
1. Turn the crankshaft to set the #1 cylinder to T.D.C. On
the compression stroke.
2. Install the valve camshaft and injection pump camshaft.
3. Install the idler gear so that the timing marks on it are
aligned with the marks on the other gears.
4. Check that the timing gears are all in alignment.
GEAR
TIMING
MARKS
VALVE CAMSHAFT REMOVAL
If only the camshaft is being removed, use the following pro-
cedure:
1. Dismount the cylinder head assembly.
2. Pull out the push rods.
3. Pull out the tappets.
4. Remove the gear case assembly.
5. Remove the camshaft stopper bolt.
6. Draw out the camshaft assembly.
INJECTION PUMP CAMSHAFT REMOVAL
1. Disconnect the injection pumps.
2. Remove the injection pump assembly.
3. Remove the gear case.
4. Remove the shaft rear cover.
5. Pull the shaft out to the front side.
.INJECTION
PUMP
CAMSHAFT