Westerbeke 55A FOUR User manual

SERVICE MANUAL
55A FOUR
MARINE DIESEL ENGINE
PUBLICATION #43377
1 st Edition / September 1998
WESTCRBEKE CORPORATION· MYLES STANDISH INDUSTRIAL PARK
150 JOHN HANCOCK ROAD, TAUNTON, MA 02780-7319 U.S.A.

CALIFORNIA
PROPOSITION 65 WARNING
Diesel engine exhaust and some
of its constituents are known to
the State of California to cause
cancer, birth defects, and other
reproductive harm.
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
-Nausea
-Headache
- Weakness and Sleepiness
- Throbbing in Temples
- Muscular Twitching
- Vomiting
-Inability to Think Coherently
IF YOU OR ANYONE ELSE EXPERIENCE ANY OF THESE SYMPTOMS,
GET OUT INTO THE FRESH AIR IMMEDIATELY. «symptoms persist,
seek medical attention. Shut down the unit and do not restart
untilit has been inspected and repaired.

SAFETY INSTRUCTIONS
INTRODUCTION
Read these safety instructions carefully. Mostaccidents are
causedbyfailure tofollowfuruklmental rules
and precau-
tions.
Know when dangerous conditions exist and take the
necessaryprecautions to protectyourself,
your personne~
and your machinery.
Thefollowing safety instructions are in complWnce with
theAmerican Boat and Yacht Council(ABYC) staruklrds.
PREVENT ELECTRIC SHOCK
A WARNING: Do not touch AC electrical connections
while engine is running, or when connected to shore
power. 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 not 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 ifthis procedure is not followed.
• Electrical shock results from handling a charged capacitor.
Discharge capacitor
by shorting terminals 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 line, carburetor, or fuel filters.
• Do not operate with a Coast Guard Approved flame
arrester 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/gener-
ator clean and free
of debris to minimize the chances of
fire. Wipe up all spilled fuel and engine oil.
• Be aware -diesel fuel 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 run-
ning 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 servic-
ing. 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 shutoffvalve.
• 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.
Engines & Generators
i

SAFETY INSTRUCTIONS
ACCIDENTAL STARTING
A WARNING: Accidental starting can cause injury
Dr death!
• 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.
BAnERY EXPLOSION
A WARNING: Battery explDsiDn can cause injury
Dr 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 dur-
ing servicing.
• Never connect the negative (-) battery cable to the posi-
tive (+) 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
burns
or sparks that could cause an explosion. Remove
wristwatch, rings, and any other jewelry before handling
the battery.
• Always turn the battery charger off before disconnecting
the battery connections. Remove the negative lead first
and reconnect it last when servicing the battery.
BAnERYACID
A WARNING: Sulphuric acid in batteries can cause
severe injury Dr death!
• When servicing the battery or checking the electrolyte
level, wear rubber gloves, a rubber apron, and eye protec-
tion. 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.
TOXIC EXHAUST GASES
A WARNING: CarbDn mDnDxide (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 ABYCT-22 (educa-
tional information on Carbon Monoxide).
A WARNING: CarbDn mDnDxide (CO) is an invisible
DdDrless gas. InhalatiDn prDduces flu-like symptDms,
nausea Dr death!
• Do not use copper tubing in diesel exhaust systems. Diesel
fumes can rapidly destroy copper tubing in exhaust sys-
tems. 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. Ifthe 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 symp-
toms
or signs of carbon monoxide inhalation or poison-
ing are:
Vomiting
Dizziness
Throbbing
in temples
Muscular twitching
Intense headache
Weakness and sleepiness
AVOID MOVING PARTS
A WARNING: Rotating parts can cause injury
Dr death!
• Do not service the engine while it is running. If a situation
arises in which it is absolutely necessary to make operat-
Engines & Generators
ii

SAFETY INSTRUCTIONS
ing adjustments, use extreme care to avoid touching
moving parts and hot exhaust system components.
• Do not wear loose clothing or jewelry when servicing
equipment; 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: 00 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.
ENGINE INSTALLATIONS
Preparations to install an engine should begin with a thor-
ough examination
of the American Boat and Yacht Council's
(ABYC) standards. These standards are a combination
of
sources including the USCG and the NFPA.
Sections
of the ABYC standards of particular interest are:
H-2 Ventilation
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"
OrderFrom:
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, MA02322
USCG (United States Coast Guard)
"USCG 33CFR183"
OrderFrom:
U.S. Government Printing Office
Washington, D.C. 20404
Engines & Generators
iii

INSTALLATION
When installing WESTERBEKE engines and generators it is important that strict
attention be paid to the following infonnation:
CODES AND REGULATIONS
Strict federal regulations, ABYC guidelines, and safety codes must be complied with
when installing engines and generators in a marine environment.
SIPHON-BREAK
For installations where the exhaust manifold/water injected exhaust elbow is close to
or below the vessel's waterline, provisions must be made to install a siphon-break in
the raw water supply hose to the exhaust elbow. This hose must be looped a minimum
of 18" above the vessel's waterline. Failure to use a siphon-break when the exhaust
manifold injection port
is at or below the load waterline willresult in raw water
damage
to the engine and possibleflooding of the boat.
EXHAUST SYSTEM
The exhaust hose must be certified for marine use. The system must be designed to
prevent water from entering the exhaust under any sea conditions and at any angle
of the vessels hull.
A detailed 40 page Marine Installation Manual covering gasoline and
diesel, engines and generators, is available from your WESTERBEKE
dealer.
Engines & Generators
iv

TABLE OF CONTENTS
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
55A FOUR Specifications
............................. 4
Parts Identification .................................. 5
Testing for Overhaul
................................. 6
Engine Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Engine Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.. 11
Engine Inspection and Repair. . . . . . . . . . . . . . . . . . . . . . . . .. 16
Engine Reassembly .............. :................... 26
Engine Adjustments ................................. 42
Glow Plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 51
Lubrication System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 52
Remote Oil Filter (Optional) . . . . . . . . . . . . . . . . . . . . . . . . .
.. 57
Coolant
Pump ...................................... 58
Raw
Water Pump ................................... 59
Heat Exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.. 60
Intake/Exhaust Manifold ............................. 61
Tachometer ........................................ 62
Starter Motor ...................................... 63
DC Electrical System/Alternator ....................... 67
DC Electrical System -Wiring Diagram ................ 70
DC Electrical System -Wiring Schematic .... . . . . . . . . . .. 71
Transmissions ...................................... 72
Service Standards
................................... 73
Metric Conversions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 77
55A FOURTorques . . . . . . . . . . . . . . . . . . . . . .
.. . . . . . . . . .. 78
Standard Hardware Torques, General Screws, Sealants " .
.. 79
Index................................. ............. 80
Engines &Generators
1

INTRODUCTION
ENGINE OVERHAUL
This service manual contains detailed information relating to
the overhaul
of the 55A FOUR Diesel Engine. For the major
overhaul procedure, refer to the ENGINE DISASSEMBLY,
ENGINE INSPECTIONAND
REPAIR, and ENGINE
REASSEMBLYsections. Additional service information for
specific components and systems may be found by referring
to the
Table of Contents and the Index. Refer also to your
WESTERBEKE Parts Catalog.
These service procedures are intended for the guidance
of
suitably equipped and staffed marine engine service and
rebuilding facilities, and should only
be undertaken by such-
facilities and their personnel.
PRODUCT SOFTWARE
Product software (tech data, parts lists, manuals, brochures
and catalogs) provided from sources other than WESTER-
BEKE are not within WESTERBEKE'S control.
WESTERBEKE CANNOTBE RESPONSIBLE FOR THE
CONTENTOFSUCH SOFTWARE, MAKES NO WAR-
RANTIES OR REPRESENTATIONS WITH RESPECT
THERETO, INCLUDINGACCURACY, TIMELINESS OR
COMPLETENESS THEREOFAND WILL INNO EVENT
BELIABLE FOR
ANY TYPE OFDAMAGE OR INJURY
INCURRED
IN CONNECTION WITH OR ARISING OUT
OF
THE FURNISHING OR USE OFSUCH SOFTWARE.
WESTERBEKE customers should also keep in mind the
time span between printings
of WESTERBEKE product soft-
ware and the unavoidable existence
of earlier WESTER-
BEKE manuals. Product software provided with
WESTERBEKE products, whether from WESTERBEKE
or
other suppliers, must not and cannot be relied upon exclu-
sively as the definitive authority on the respective product.
It
not only makes good sense but is imperative that appropriate
representatives
of WESTERBEKE or the supplier in question
be consulted to determine the accuracy and currentness
of the
product software being consulted by the customer.
NOTES, CAUTIONS AND WARNINGS
As this manual takes you through the service procedures and
troubleshooting
of your marine engine, critical information
will be highlighted by
NOTES, CAUTIONS, and WARNINGS.
An explanation follows:
NOTE: An operatingprocedure essential to note.
A CAUTION: Procedures. which if not strictly
observed. can result in the damage or destruction of
your engine.
A WARNING: Procedures, which if not properly fol-
lowed. can result in personal injury or loss of life.
CUSTOMER IDENTIFICATION CARD
1-WV-IWESIE'RBEKE
I
Customer Identification
MR. ENGINE OWNER
MAIN STREET
HOMETOWN, USA
Model 55A FOUR Ser. #UOOOO-D702
Expires 4/4/98
The WESTERBEKE engine serial number is an alphanu-
meric number that can assist in determining the date of man-
ufacture
of your WESTERBEKE engine. The manufacturer's
date code is placed at the end
of the engine serial number and
consists
of a character followed by three numbers. The char-
acter indicates the decade (A=1960s, B=1970s, 0=1980s,
D=1990s), the first number represents the year in the decade,
and the second and third numbers represent the month of
manufacture.
ORDERING PARTS/SERIAL NUMBER LOCATION
Whenever replacement parts are needed, always provide the
engine model number and engine serial number as they
appear on the silver and black identification nameplate
located on the side
of the manifold. The engine serial number
can also be found stamped into the engine block just above
the injection pump.You must provide us with this informa-
tion so we may properly identify your engine. 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 specifi-
cations as original equipment.
NOTE: Component locations in this manual are referenced
from the front of the engine which is thepulley/drive belt end.
Left and right sides are determined as follows: imagine
straddling the
engine, facing in the same direction as the
front
of the engine: the left side is at your left, the right side
is atyour right.
Owners may find it convenient to fill in the engine identifica-
tion nameplate shown below toprovide a quick reference
when using this service manual
Engines & Generators
2

INTRODUCTION
55A FOUR DIESEL ENGINE
SPRING RETAINER
INJECTION NOZZLE
CYLINOER HEAD BOLT
, PRE-CHAMBER
LOWER SPRING SEAT
t:jJ..I...-r~~~~r===d~~~~~~;;;:~~--'--- COMBUSTION
CHAMBER INSERT
Engines & Generators
3

55A FOUR SPECIFICATIONS
ENGINE SPECIFICATIONS
Engine Type
Governor
Valve Mechanism
Combustion Chamber
Bore and Stroke
Piston Displacement
Firing Order
Direction of Rotation
Maximum Torque
(at 1920 rpm)
Compression Ratio
Compression Pressure
Valve Seat Angle
Valve Clearance
(engine cold)
Dimensions
InClination
Dry Weight
Engine Speed
Fuel Consumption
Diesel, four-cycle, four-cylinder, fresh-
water-cooled, vertical, in-line (55 hp at
3600 rpm maximum)
Integral with the injection pump,
mechanical centrifugal flyweight type
Direct drive, OHC
Swirl chamber type
3.38 x 3.70 inches (86.0 x 94.0 mm)
133.2 cubic inches (2.18 liters)
1-3-4-2
Clockwise, when viewed from the front
of the engine (pulley drive belt end)
931b-ft (12.9 kg-m)
22.7:1
426 psi (30 kg/cm2) at 200 rpm
Intake 45°, Exhaust 45°
Intake .008 - 0.012 in. (0.20 - 0.30mm)
Exhaust 0.012-0.016 in. (0.30-0.40 mm)
Height: 26.78 inches (680.2 mm)
Width: 50.0 inches (546.1 mm)
Length: 35.0 inches (889.0 mm)
Continuous 14°; Temporary 25°
(not to exceed 30')
470 Ibs (213.2 kgs)
Idle speed: 750 -1000 rpm
Cruising speed: 2500 - 3000 rpm
1.5 U.S. gph (5.6 Iph) running at 2500
rpm (approximate) when the propeller
allows 3600 rpm at full open throttle
while underway in forward gear
FUEL SYSTEM
Fuel
Injection Pump
Injection Timing
Injectors
Injection Pressure
Lift Pump
Fuel Filter (on engine)
Fuel Supply and
Return Piping
Air Cleaner
Air Flow
(engine combustion)
(engine cooling)
No.2 diesel oil
(cetane rating of 45 or higher)
Zexel mechanical governed
OOTDC
Throttle type
1920 psi + 71 psi
(135 kg/cm2 +5 kg/cm2)
12 volt - plunger type
Spin-on type (replaceable)
.250 in (.635 mm) 1.0. minimum
.375 in (.925 mm) 1.0. maximum
Replaceable paper filter element
140 cfm (3.9 cmm) at 3600 rpm
250 cfm (7.0 cmm)
EXHAUST SYSTEM
Exhaust Elbow
Exhaust Hose Size
Muffler Size (min.)
90° elbow, 45° elbow and exhaust riser
2 inch 1.0. hose
14 inch x 14 inch
COOLING SYSTEM
General
Operating Temperature
Coolant Pump
Raw Water Pump
Raw Water Flow,
at 3600 rpm
Freshwater-cooled block, thermostati-
cally controlled with raw water
exchanger system
170 - 190°F (77 - 88°C)
Centrifugal type, metal impeller, belt-
driven
Positive displacement, rubber impeller,
belt driven
16.0 gpm (60.5 Ipm) approximate
(measured before discharg-
ing into exhaust elbow)
Coolant System Capacity 9.5 U.S. qts (9.0 liters)
ELECTRICAL SYSTEM
Starting Battery
BaHery Capacity
Starter Motor
Starting Aid
DC No-Load Current
Cold Cranking Current
Alternator (standard)
Regulator
12-volt DC, (-) negative ground
300 - 400 Cold cranking amps (CCA)
(min.)
12-volt, 1.6kw, SOlenoid, actuated shift
reduction gear
12 volt sheathed type glow plug
100 amps at 11.5 volts (3000 rpm,
min.)
280 - 300 amps at 10 volts (250 rpm,
min.)
12-volt, DC, 50 amps
Internal regulator, built into alternator
TRANSMISSION
General
Gear ratio (standard)
Propell er Shaft
Direction of Rotation
Propeller
Recommendations
(using standard
transmission
2.74:1 reduction)
Lubricating Fluid
Transmission Sump
Oil Pump
Oil Filter
Lube Oil Cooler
Lubricant Capacity
Sump Capacity
Operating Oil Pressure
Oil Grade
(Hurth Standard Transmission) Case-
hardened helical gears, with a servo-
operated multiple disc clutch.
2.74: 1 (HBW250 - 3R)
Right handed - standard transmission
20 Dx 13 P- 2 blade or 200 x 11 P- 3
blade propeller should allow the engine
to reach its full rated rpm (3600 + 000
- 100) at full open throttle while under-
way in forward gear.
ATF- type A or Dextron -/I or 11/
0.79 U.S. qts (0.75 liters) approximate
Crescent type directly driven by the.
crankshaft.
Full flow, paper element, spin-on type
Fresh water cooled.
1.75 U.S. gal. (6.6. liters)
5.0 U.S. qts (4.8 liters) not including filter
30 - 60 psi (2.1 - 4.2 kg/cm2) at maxi-
mum engine rpm and at normal oper-
ating temperature
API Specification CF or CG-4,
SAE 30, 10W-30, 15W-40
Engines & Generators
4

WATER 'I'M""",UI
SENDER
LUBE OIL DRAIN HOSE
TRANSMISSION
SHIFT LEVER
FRONT
REAR
PARTS IDENTIFICATION
OIL PRESSURE SENDER STARTER WITH SOLENOID
LEFT SIDE
UNIT I. D. PLATE AIR CLEANER HOUSING
RIGHT SIDE
'" A
Engines & Generators
5
ANODE
BATTERY GROUND CONNECTION
REAR
MANIFOLD PRESSURE CAP
OIL COOLER
FRONT
DOMESTIC
WATER HEATER
CONNECTION POINTS
RAW WATER PUMP
LUBE OIL FILTER

TESTING FOR OVERHAUL
HOW TO DETERMINE WHEN
TO OVERHAUL THE ENGINE
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,
in the case
of diesel engines, is not necessarily due to trouble
with the engine itself, but is sometimes caused by injector
nozzle wear
or injection pump wear. It is most reasonable to
judge by a decrease in compression pressure. The decrease in
compression pressure is caused by many factors.
Itis, there-
fore, 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 pis-
ton rings, the following symptoms will occur:
• Low engine power output
• Increased fuel consumption
• Increased oil consumption
• Hard engine starting
• Noisy engine operation
These symptoms often appear together. Increased fuel con-
sumption and hard engine starting can result also from exces-
sive fuel injection, improper injection timing, and wear
of
plugs and nozzles. They are caused also by defective electri-
cal 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 consump-
tion. In diesel engines, 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.
Measuring Compression Pressure
To check the compression pressure, see COMPRESSION
TEST under ENGINEADJUSTMENTS.
NOTE: Do not guess the conditions of other cylinders from a
result
of testing one cylinder. Be sure to measure the com-
pression pressure for
each cylinder. Lookfor cylinders with
dramatically (at least20%) lower compression than the aver-
age
of the other cylinders. If the weak cylinder isflanked by
healthy cylinders, the problem
is either valve- or head-gasket
related. Very low compression in an adjacent cylinder indi-
cates gasket
failure. Abnormally high readings on all cylin-
ders indicate heavy carbon accumulations, a condition that
might be accompanied
by high pressures and noise.
NOTE: In case of severe vibrations and detonation noise,
have the injectors overhauled by an authorizedJueI injection
service
center. Poorfuel quality, contaminates, and loss of
positive fuel pressure to the injection pump will result in
injector faults.
OVERHAUL CONDITIONS
Compression pressure tends to increase a little in a new
engine until the piston rings and valve seats have been bro-
ken in. Thereafter, it decreases gradually with the progressive
wear
of these parts. Engine compression should be 30 kg/cm2
(at 200 rpm).
When the decrease
of compression pressure reaches its limit
(see SERVICE STANDARDS), the engine must
be over-
hauled. The engine also requires an overhaul when oil con-
sumption is high, when blowby is evident, and when
compression values are at minimum or below.
NOTE: Refer to the SERVICE STANDARDS chart during an
engine overhaul. It gives the measurements and values for
the repair or replacement of the engine components.
Engines & Generators
6

ENGINE TROUBLESHOOTING
The following troubleshooting table describes certain
problems relating to engine service, the probable causes of
these problems, and the recommendations to overcome
these problems.
Note: The engine's electricalsystem is protected by a 20-
ampere manual reset circuit breaker. The preheat solenoid is
mountedon the same bracket.
PROBLEM PROBABLE CAUSE VERIFICATION/REMEDY
HARD STARTING
LOW CRANKING SPEED
1. Engine oil viscosity too high. 1. Replace engine oil with less viscous oil.
2. Run-down battery. 2. Recharge battery.
3. Worn battery. 3. Replace battery.
4. Battery terminals loosely connected. 4. Clean terminals and correct cables.
5. Defective starter. 5. Repair or replace starter.
6. Defective main drive section. 6. Check clutch for disengagement.
DEFECTIVE INJECTION SYSTEM
1. Air trapped in fuel passage. 1. Bleed air from fuel system.
2. Clogged fuel filter.
2. Clean or replace filter.
3. Low injection pressure. 3. Adjust injection pressure.
4. Inadequate spray. 4. Clean or replace nozzle.
5. Injection pump delivering insufficient fuel. 5. Repair or replace injection pump.
6. Injection too early. 6. Adjust injection timing.
ENGINE TROUBLES
1. Low compression.
a. Incorrect valve clearance. a. Adjust valve clearance.
b. Inadequate contact of valve seat. b. Lap valve.
c. Valve stem seized. c. Replace valve and valve guide.
d. Broken valve spring. d. Replace valve spring.
e. Compression leaks through cylinder head gasket. e. Replace gasket.
I. Cracked or distorted cylinder head. I. Replace cylinder head.
g. Piston ring seized. g. Replace piston and piston ring.
h. Worn piston ring and cylinder. h. Overhaul engine.
i. Cracked or wom piston. i. Replace piston.
2. Burnt glow plug.
2. Replace glow plug.
3. Faulty glow plug operation. 3. Check glow plugs and solenoid.
4. Incorrect governor lever pOSition. 4. Set lever to starting position.
5. Governor spring out of position. 5. Correct spring.
POOR IDLING 1. I mproper valve clearance. 1. Adjust valve clearance.
2. Poor valve to valve seat contact. 2. Repair or replace.
3. Failure of cylinder head gasket.
3. Replace gasket.
4. Malfunction of fuel system. 4. See LOW OUTPUT and ROUGH OPERATION.
LDW OUTPUT LOW COMPRESSION See Low Compression under 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 nozzle 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
7

ENGINE TROUBLESHOOTING
PROBLEM
PROBABLE CAUSE VERIFICATION/REMEDY
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. 4. Add engine oil.
EXCESSIVE OIL OIL
LEAKAGE
CONSUMPTION 1. Defective oil seals. 1. Replace oil seals.
2. Loose oil filter.
2. Tighten.
3. Broken cylinder head cover gasket. 3. Replace gasket.
4. Damaged cylinder head cover. 4. Replace.
5. Damaged front housing gasket. 5. Replace.
6. Loose oil pipe connector. 6. Retighten oil connections.
7. Loose bolt(s) at oil pump body, cylinder head 7. Tighten.
covers or oil pan.
8. Loose or damaged oil pressure switch. 8. Tighten or replace.
9. Defective seal at oil pan and cylinder block.
9. Repair.
10. Loose drain plug. 10. Retighten or replace.
OIL LEVEL RISING
1. Incorrectly positioned piston ring gaps. 1. Correct ring gap positions.
2. Displaced 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. 2. Replace valve and valve guide.
OIL PRESSURE DROP 1. Oil leak.
1. See OIL LEAKAGE
2. Insufficient oil. 2. Add oil.
3. Worn and/or damaged oil pump gear. 3. Replace.
4. Worn oil pump plunger or weak spring.
4. Replace.
5. Clogged oil strainer. 5. Clean.
6. Excessive lubrication clearance between main 6. See Crankshaft Assembly under
bearing and connecting rod bearing. ENGINE REASSEMBLY.
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 under HARD STARTING.
5. Improper valve timing. 5. Adjust.
6. Improper valve clearance. 6. Adjust.
INSUFFICIENT INTAKE AIR
1. Air intake obstructed.
1. Clean and remove obstruction.
NOZZLE TROUBLES
1. Seized nozzle. 1. Replace.
2. Worn nozzle.
2. Replace.
IMPROPER FUEL Replace with proper fuel.
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)
Engines &Generators
8

ENGINE TROUBLESHOOTING
PROBLEM
PROBABLE CAUSE
VERIFICATION/REMEDY
SMOKY EXHAUST (cont.) 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 under HARD STARTING.
BLACKISH OR DARK GRAYISH
1. Engine body troubles.
a. Poor compression. a. See Low compression under 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. Main bearing worn, heat-damaged or seized. 1. Replace bearing and grind crankshaft.
2. Excessive main bearing oil clearance. 2. Replace bearing.
3. Melted main bearing. 3. Replace bearing and check lubrication system.
4. Badly worn crankshaft.
4. Grind crankshaft.
5. Excessive crankshaft end play. 5. Adjust end play.
CONNECTING ROD AND CONNECTING ROD BEARING
1. Connecting rod big end bearing worn, 1. Replace bearing.
heat-damaged or seized.
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 or piston pin. 2. Replace piston.
3. Piston seized. 3. Replace piston and rebore cylinder.
4. Piston seized and rings worn or damaged. 4. Replace piston and rings.
5. Bent connecting rod. 5. Replace connecting rod.
VALVE MECHANISM
1. Worn camshaft.
1. Replace camshaft.
2. Excessive valve clearance. 2. Adjust valve clearance.
3. Broken valve spring. 3. Replace valve spring.
4. Worn timing gear. 4. Replace timing gear.
OTHER
1. Fresh water pump bearing malfunction. 1. Replace bearing.
2. Incorrect drive belt tension. 2. Adjust.
3. Alternator bearing malfunction. 3. Replace bearing.
4. Exhaust gas leakage. 4. Repair.
5. Timing belt tensioner malfunction. 5. Replace tensioner.
ROUGH OPERATION INJECTION PUMP SYSTEM
(HUNTING)
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 delivery valve.
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 spring.
(continued)
Engines &Generators
9

ENGINE TROUBLESHOOTING
PROBLEM
PROBABLE CAUSE
VERIFICATIONJREMEDY
KNOCKING ENGINE KNOCKS WITHOUT MUCH SMOKE
1. Engine troubles.
8. Overheated cylinder. 8. See OVERHEATING; LOW OUTPUT.
b. Carbon deposits in cylinder. b. Clean.
2. Too early injection timing. 2. Correct.
3. Too high injection pressure. 3. Correct.
4. Improper fuel. 4. Replace with proper fuel.
KNOCKING WITH DARK SMOKE
1. Poor compression. 1. See Low compression under HARD STARTING.
2. Injection pump malfunctioning.
8. Worn plunger. 8. Replace.
b. Pinion is not in mesh with control rack. b. Correct.
c. Broken delivery valve spring. c. Replace.
d. Worn delivery valve seat. d. Replace.
3. Improper nozzle.
8. Poor spray. 8. Clean or replace nozzle.
b. Poor chattering. b. Repair or replace nozzle.
c. After-injection drip. c. Repair or replace nozzle.
d. Nozzle needle valve seized. d. Replace.
INTERMITTENT 1. Fuel filter clogged. 1. Clean or replace.
EXHAUST SOUND
2. Fuel pipe sucks air. 2. Retighten pipe joints or replace pipe.
3. Water mixed in fuel 3. Replace fuel.
OVERHEATING 1. V-belt slackening or slippery with oil. 1. Adjust, replace or clean.
2. Damaged water pump. 2. Replace.
3. Lack of coolant. 3. Add.
4. Low oil level or poor oil quality. 4. Add or change.
5. Knocking.
5. See KNOCKING.
6. Moving parts seized or damaged. 6. Replace.
Engines & Generators
10

ENGINE DISASSEMBLY
NOTE: Before disassembly and cleaning, carefully check
for defects which cannot
be found afterdisassembly and
cleaning.
GENERAL DISASSEMBLY PROCEDURE
• All disassembled parts should be carefully arranged in
the 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 disassem-
bled 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 parts that require no disas-
sembly.
• Carefully inspect each part after removal for damage,
4eformation, and other problems.
• Be careful not to damage the disassembled parts. Keep
the parts clean.
• Use the proper tools. Apply oil when necessary. Take
special care to keep the fuel system parts free from the
intrusion
of dust and dirt.
• Remove the transmission first, then disassemble the
engine.
TRANSMISSION REMOVAL
1. Unplug the instrument panel wiring harness.
2. Drain the transmission fluid and the transmissin oil
cooler hoses
3. Detach the oil cooler hoses.
4. Unbolt the transmission from the engine.
NOTE: For transmission service and maintenance, refer to
your transmission
owner~ manual. To rebuild a transmis-
sion, contactyour WESTERBEKE dealer or a qualified
marine transmission servicefacility.
ENGINE DISASSEMBLY
1. Clean the exterior of the engine of any deposits of dirt
and oil.
2. Mount the engine on a suitable engine stand for disas-
sembly.
3. Drain the coolant from the engine and the heat
exchanger. Drain the fuel and the engine oil.
4. Remove the engine wiring harness in its entirety. Label
the terminal connections to insure proper reattachment.
5. Remove the engine heat exchanger and the engine oil
cooler/oil filter assembly.
If possible, leave one end of
each hose connection attached to the part being removed.
6. Remove the starter motor.
7. Remove the engine bellhousing.
8. Remove the transmission damper plate.
9. Remove the flywheel.
10. Remove the engine back plate.
11. Unclamp the exhaust elbow, the two coolant hoses on the
exhaust manifold, and the coolant recovery tank hose,
then remove the intake/exhaust manifold in its entirety
with its four gaskets.
EXHAUST
ELBOW
12. Remove the alternator.
13. Remove the raw water pump.
COOLANT
RECOVERY
TANK
. INTAKEJEXHAUST
MANIFOLD
14. Remove the engine mounted fuel filter and the fuel line
to the injection pump. (Note the arrangement
of the seal- .
ing washers on the banjo bolts at the fuel filter and the
injection pump). Remove the fuel lift pump.
15. Remove the thermostat housing, gasket, and the thermo-
stat. Leave the temperature sending unit in place.
Engines &Generators
11

ENGINE DISASSEMBLY
16. Remove the idler pulley bracket and idler pulley.
17. Remove the seal plate.
18. Remove the coolant pump.
19. Remove all the high pressure injector lines from the
injection pump to the injectors. Leave the two upper line
clamps in place.
NOTE: Cap the ends of the lines, and the connections at
the injection pump and at the injectors, to prevent entry
of foreign material.
20. Remove the fuel return lines from the top of the injectors
and from the fuel injection pump. (Note the washer arrange-
ment on the fuel return line banjo bolts. Cap all openings
on the fuel return line, injectors and injection pump.)
21. Remove the fuel injectors, dust seals and sealing washers
from the cylinder head.
22. Remove the glow plugs.
23. Remove the cylinder head cover.
24. Fuel Injection Pump.
NOTE: The fuel injection pump is a very important compo-
nent
of the diesel engine, requiring the utmost care in
handling. It has been thorol,tghly bench-tested, and the
owner/operator is cautioned not to attempt to service it. If
the fuel injection pump requires servicing, remove it and
take it to an authorizedfuel injection pump service
facility.
Do not attempt to disassemble and repair it. If
the pump is defective, WESTERBEKE recommends that
you replace the entire pump.
The only adjustment the servicing mechanic should
make to the fuel injection
pump is the adjustmentfor
engine idle speed (see IDLE SPEED
ADJUSTMENT
under ENGINEADJUSTMENTS).
Fua INJECTION PUMP
Remove the injection pump as follows:
NOTE: Scribe mating I -: .. :" ~
marks on the pump body / ~
flange and the timing belt
cover before removal.
MATING
MARKS
3. Remove the two timing belt covers.
b. Loosen the two injection pump hold-down nuts. Do
not remove them entirely. The hold-down nut on the
engine side
of the pump can be loosened by using a
1/4" universal socket and extension with a ratchet.
c. Remove the nut and lockwasher from the injection
pump shaft.
d. Place the keyway on the injection pump shaft in the 12
o'clock position using the front crankshaft pulley bolt
before attempting to remove the injection pump.
e. Using the puDey puDer (49 S120 215A), apply suffi-
cient pressure to loosen the pump from the pulley. The
loose hold down nuts will prevent the pump from
falling from the engine.
NOTE: If an extractor is not available, replace the nut
loosely on the injection pump shaft, and with a nylon
drift and hammer, gently tap the injection
pump shaft
to dislodge
it from the keyedpulley.
INJECTION
PUMP PULLEY
;:r~~ffl~I---- PULLEY PULLER
.49 S120 215A
f. Once loosened, remove the hold down nuts and wash-
ers and carefully withdraw the pump from the pulley
and the engine.
25. Remove the following components:
3. Oil pressure switch and oil level gauge.
b. Dipstick tube.
c. Cylinder head cover.
d. Crankshaft pulley.
e. Oil strainer and oil pan.
f. Oil pump assembly.
g. Rear cover.
h. Connecting rod caps.
i Pistons and connecting rods.
j. Piston rings.
k. Main bearing caps.
L Main bearings.
m.Oiljets.
D. Crankshaft.
Engines & Generators
12

ENGINE DISASSEMBLY
nming Belt
NOTE: WESTERBEKE recommends replacing the timing
belt during an engine overhaul. Timing beltfailure could
result in major damage to the engine.
NOTE: If the tming belt is to be reused, draw an arrow on
the beltpointing in the direction
of the belt's rotation so it
will be replaced in the same direction.
DIRECTION ARROW ___ ''--01
TIMING
BELT
1. Loosen the timing belt tensioner lock bolt, push the tim-
ing belt tensioner left as far as
it will go, then temporarily
retighten the lock bolt.
2. Remove the timing belt.
3. Remove the timing belt tensioner.
4. Tum the crankshaft clockwise about 45° from the timing
mark which is marked on the oil pump housing.
NOTE: Turning the crankshaftprevents the pistons and
valvesfrom contacting one another.
TIMING MARK
CRANKSHAFT
Injection Pump Pulley
1. Put two bolts (size M8 x 1.25 x 35 -40 mm) through the
arms
of the injection pump pulley and insert them in the
thread hole
of the injection pump bracket.
NOTE: This is to prevent the injection pumppulley from
turning while loosening the injection pumppulley lock bolt.
2. Loosen the injection pump pulley lock bolt.
3. Using the pulley
puller (49 S120 215A), separate the
injection pump pulley from the injection pump shaft.
INJECTION
PUMPPULLE"t.
~~n~~,- __ PULLEY PULLER
~ 49 S120 215A
Engines &Generators
13

ENGINE DISASSEMBLY
Camshaft Pulley & Timing Belt Pulley
1. Hold the camshaft with a wrench (29 mm, 1.1 in) and
loosen the camshaft pulley lock bolt.
CAMSHAFT
PULLEY
LOCK BOLT--4I.IZ
A CAUTION: Do not damage the edge of the
cylinder head with the wrench. If it is damaged,
engine oil may leak.
A CAUTION: Before removing the camshaft pul-
ley, turn the crankshaft 45" clockwise to prevent
damage to the valves.
2. Remove the camshaft pulley from the camshaft using the
same procedure described underInjection PumpPulley,
above.
A CAUTION: Do nothit the camshaft pulley with
a hammer.
CAMSHAFT PULLEY
3. Remove the timing belt pulley.
Cylinder Head Bolts
1. Loosen the cylinder head bolts in the numbered sequence
shown in the ilustration. Loosen them a little at a time,
in
sequence.
1 3 5 4 2
CYLINDER HEAD BOLTS
Cylinder Head and Gasket
1. Remove the cylinder head by tapping it with a plastic
hammer.
2. Remove the cylinder head gasket.
Camshaft
1. Gradually loosen the camshaft cap nuts in the numbered
sequence shown
in the illustration.
2. Remove the caps.
3. Remove the camshaft and oil seals.
3 7 10 6
4 8 9
5·
LOOSENING THE CAMSHAFT CAP NUTS
Adjusting Discs and Tappets
1. Remove the adjusting discs and tappets as a set.
A CAUTION: All adi~ing discs and tappets
should be disassembled in a way that-COllect
reassembly can be performed efficiently.
2
1
Engines & Generators
14