Westerbeke 12B TWO User manual

OPERATOR'S MANUAL
WESTERBEKE 12BTWO
MARINE DIESEL
ENGINE
Publication # 37185
Edition One
January 1988
....v- WESJ'ERBEKE
WESTERBEKECORPORATION
AVON INDUSTRIAL PARK, AVON, MA 02322. TEL: [phone]

SAFETY PRECAUTIONS
The following symbols appear in this manual to call attention
to and emphasize conditions potentially dangerous to the
operator.
IWARNING\
The above symbol is used in the manual to warn of possible
serious personal injury or loss of life.
CAUTION
The above symbol is used in the manual to caution personnel
of possible
damage to equipment
Read the manual carefully and thoroughly before attempting
to operate the equipment. Know when dangerous conditions
can exist and take necessary precautions to protect personnel
and equipment.
Fuels, exhaust gases, batteries, electrical equipment, and
moving and
hot parts are potential hazards that could result in
serious personal injury or death. Follow recommended proce-
dures carefully.
Always operate bHge blowers for at least five minutes before
starting agasoline-fueled engine; ensure no gasolinefumesare
present before starting.
.. Prevent Electric Shock
Shut off electric power before accessing electrical equip-
ment.
Use insulated mats whenever working on electrical equip-
ment.
Make sure your clothing is dry,
not damp (particularly
shoes),
,and keep your skin surfaces dry when handling
electrical equipment.
Remove wristwatch and jewelry when working on electri-
cal equipment.
Do
not connect utility shore power to vessel's AC circuits,
except through a shipAo-shore double-throw transfer
switch. Damage
to vessel'sAC generator may result if this
is
not done.
Be extremely careful when working on electrical com-
ponents. High voltage can cause injury or death.
• Exhaust Gases Are Toxic
Ensurethattheexhaustsystem is adequate to expel gases
discharged from the engine. Check exhaust system
regularly for leaks and make sure the exhaust manifolds
are securely attached and
no warping exists.
Be sure the
unit and its surroundings are well-ventilated.
• Use Extreme Care When Handling Engine Fuel
(A constant danger of explosion orfire exists)
Do not fill fuel tank(s) while the engine is running.
Do not smoke or use an open flame nearthe engine orthe
fuel tank.
• Do Not Alter or Modify the Fllel System
Be sure all fuel supplies have a positive shut-off valve.
Be certain fuel line fittings are adequately tightened and
free of leaks.
Make sure a
1ire extinguisher is installed nearby and is
properly maintained.
Be familiar with its proper use. Ex-
tinguishers rated ABC by the NFPA are appropriate for all
applications encountered in this environment.
• Use Extreme Care When Servicing Batteries
Wear rubber gloves, a rubber apron, and eye protection
when servicing batteries.
Lead acid batteries emithydrogen, ahighly-explosive gas,
which can be ignited
by electrical arcing or by a lighted
cigarette, cigar, or pipe. Do not smoke or allow an open
flame near the battery being serviced. Shut off all electri-
cal equipment
in the vicinity to prevent electrical arcing
during servicing.
• Ayoid Moving E.a!:1l>
Do not service the unit while the unit is running; if a situa-
tion arises
in which it is absolutely necessary to make
operating adjustments, use extreme care to avoid moving
parts and hot exhaust system components.
Do not wear loose clothing or jewelry when servicing
equipment; avoid wearing loose jackets, shirts or sleeves,
rings, necklaces, or bracelets that might be caught in
moving parts.
Make sure all attaching hardware is properly tightened.
Keep protective shields and guards in their respective
place at all times.
Do not check fluid levels or the drive-belt's tension while
the unit is operating.
Do notwork on the
equipment when mentally or physical-
ly incapacitated by fatigue.

IMPORTANT
PRODUCT SOFTWARE DISCLAIMER
Product software of all kinds, suchas brochures, drawings, technical data, operator'sand workshop manuals,
parts lists and parts price lists (and other related information), instructions and specifications provided from
sources other
than Westerbeke, is no! within Westerbeke's control and, accordingly, is provided to Wester-
beke customers only asa courtesy and service. WESTERBEKE CANNOT BE RESPONSIBLE FOR THE CON-
TENT OF SUCH SOFTWARE, MAKES NO WARRANTIES OR REPRESENTATIONS WITH RESPECT
THERETO, INCLUDINGTHE ACCURACY, TIMELINESS OR COMPLETENESS THEREOF, AND WILL IN NO
EVENT BE LIABLE FOR ANY TYPE OF DAMAGES OR INJURY INCURRED IN CONNECTION WITH, OR
ARISING OUT OF, THE FURNISHING OR USE OF SUCH SOFTWARE.
For example, components and subassemblies incorporated into Westerbeke's products and supplied by
others (such as engine blocks, fuel systems and components, transmissions, electrical
components, pumps
and
other products) are generally supported by their manufacturers with their own software, and Westerbeke
must depend on such software for the design 01 Westerbeke's own product software. Such software,
however,
may be outdated and no longer accurate. Routine changes made by Westerbeke's suppliers, of
which Westerbeke rarely has notice in advance, are frequently not reflected in the supplier's software until
after such changes take place.
Weslerbeke customers should also keep in mind the lime span between printings of Westerbeke product
software, andthe unavoidableexistence
of earlier, non-currentWesterbeke software editions in the field. Ad-
ditionally,
most Westerbeke products include customer-requested special features that frequently do not in-
clude complete documentation.
In summation, product software provided with Westerbeke products, whether from Westerbeke or other sup-
pliers,
must not and cannot be relied upon exclusively as the definitive authority on the respective product.
It not only makes good sense, but is imperative that appropriate representatives of Westerbeke or the sup-
plier in question be consulted to determine the accuracy and currency of the product software being con-
sulted by the customer.
1 Weslerbeke Diesel Engines

FOREWORD
Thank you for selecting a Westerbeke marine product for your use. We at Westerbeke are pleased to have
you
as a customer.
Read this manual carefully and observe all safety precautions included throughout. Operating procedures,
periodic preventive maintenance procedures, installation checks, system descriptions and minor adjust-
ment procedures are included herein so you can operate your equipment safely and properly, maintain the
equipment at a high level of efficiency, and expect dependable performance and long service life in return.
Should your unit require special attention, contact yourWesterbeke dealer for assistance. The Westerbeke
Service Organization is trained to provide the support necessary to ensure long-term dependable perfor-
mance.
If, within 60 days of submitting the Warranty Registration Form for your unit, you have not received a Cus-
tomer Identification Card (see below) registering your warranty, please contact the factory in writing with
Model information, including the engine's serial number and commission date.
from:
WESlER8EKE CORPORA liON
AVON INDUSTRIAL PARK
AVON, ~A 02322
'""fiI\T I WESTERBEKE
~
;;;:.:~;:;:;:'. ::::;;,7~:;_::;;: ~:,~ ~~~;,:=-""
CUSTOMER IDENTIFICATION
Adall Smith
Mail To: 85 Maple
Stre-et
Alden, 1M 12234
Model N 12 TWO Set.
•
1234(706
EJCpiree 7(7/88
""
....
Inspection of Equipment
The engine is shipped from the factory mounted securely and properly crated. Accessory equipment is
shipped in a separate small box, usually packed within the engine's crate.
Before accepting shipment of the engine from the transportation company, the crate should be opened and
the contents inspected for concealed damage.
If either visible or concealed damage is noted, you should
require that the delivery agent sign "Received in damaged condition" on the proper delivery receipt. Also
check the contents ofthe shipment against the packing list and make sure that the proper notation
is made
if any discrepancies exist. These noted discrepancies are your protection against loss or damage. Claims
concerning loss or damage must be made to the carrier, not to the Westerbeke Corporation.
Westerbeke Diesel Engines 2

TABLE OF CONTENTS
Section..........................................................................
Page
W 12B TWO MARINE DIESEL ENGINE
GENERAL SPECIFICATIONS ............................................ 7
W 12B TWO SYSTEM SPECIFICATIONS ......................... 8
INSTALLATION CHECKS................................................. 10
PREPARATION FOR STARTING ..................................... 21
DESCRIPTION OF INSTRUMENT PANELS .................... 23
STARTING PROCEDURE.................................................26
STOPPING PROCEDURE................................................28
FUEL SYSTEM .................................................................30
ELECTRICAL SySTEM.....................................................33
DC WIRING DIAGRAM # 36467 SHOWING
THE CAPTAINS PANEL WIRING .............................34 & 35
DC WIRING DIAGRAM #36844 SHOWING
THE ADMIRALS PANEL WIRING.............................36 & 37
COOLING SySTEM..........................................................39
LUBRICATION SYSTEM ..................................................47
HBW 50 TRANSMISSION ...............................................50
BW 3 TRANSMISSION ....................................................54
ENGINE TROUBLESHOOTING.......................................57
MAINTENANCE & ADJUSTMENTS................................. 60
LAY-UP & RECOMMISSIONING .....................................67
TABLE OF STANDARD HARDWARE
TIGHTENING TORQUES ............................................... 71
TORQUE SPECiFiCATIONS.......................................... 72
SPARE PARTS................................................................. 73
INDEX ...............................................................................74
3 Westerbeke Diesel Engines

GENERAL
Introduction
This manual contains the equipment operating procedures as well as additional information needed to help
the operator keep the equipment in proper working order. Study and follow the instructions carefully. A
planned maintenance program
is included in this manual; adhering tothe program will result in better equip-
ment performance and longer equipment life. Proper diagnosis of a problem
is the most important step to
satisfactory repair; therefore, a troubleshooting table
is included.
Understanding the Diesel Engine
The diesel engine closely resembles the gasoline engine, since the mechanism is essentially the same. The
cylinders are arranged above a closed crankcase; the crankshaft is of the same general type as that of a
gasoline engine; and the diesel engine hasthe same type of valves, camshaft, pistons, connecting rods, and
lubricating system.
Therefore,
to a great extent, a diesel engine requires the same preventive maintenance as a gasoline engine.
The most impOltant factors are proper ventilation and proper maintenance of the luel, lubricating and cool-
ing systems. Replacement of fuel and iubricating filter elements at the time periods specified is a must, and
frequent checking for contamination (that
is, water, sediment, or allege) in the luel system is also essential.
Another importantfactor is the use ofthe same brand of high detel·gent diesel lubricating oil designed specifi-
cally lor diesel engines. Be careful not to put gasoline in the diesel fuel tank(s). Gasoline does not have the
same lubricating qualities as diesel fuel; consequently, gasoline in the fuel lines will damage components
in
the fuel lift pump assembly, fuel injection pump and injectors.
The diesel engine does differ from the gasoline engine, however, in its handling and firing of fuel. The car-
buretor and ignition systems are done away with and in their place are
two components -the fuel injection
pump and the fuel injectors.
Ordering Paris
When contacting yourWesterbeke dealer, parts distributor, orthe factory concerning your Westerbeke unit,
always providethe engine'smodel and serial number, and transmission number
as theyappear onthe black
and silver "Westerbeke" plate which is mounted on the engine's exhaust manrrold. When ordering parts for
your Westerbeke engine, be sure to insist upon Westerbeke factory packaged parts, because "will fit"
or
generic parts are frequently not made to the same specifications as original equipment.
Note that component locations
in the rnanual are referenced from the front of the engine which is the pul-
ley/drive belt end. (The flywheel/transmission end is the rear end.) Left and right sides are determined by
the engine; imagine straddling the engine and facing in the same direction as the front of the engine: the left
side is at your left, the right side is your right.
Westerbeke engines and generator sets are thoroughly checked and given a final run under various load
conditions before leaving the factory. Test running the engine ensure dependable operation, long service,
and a satisfied owner.
Care at the factory during assembly, and thorough testing, have resulted in a Westerbeke diesel engine
capable of manythousands of hours of dependable service. However, the manufacturer cannot control the
treatment the unit receives
in the field. That part is up to the owner/operator.
Westerbeke Diesel
Engines
4

W 12B TWO Marine Diesel Engine
Exhaust Manifold
gOO Exhaust Elbow
Heat Exchanger
Zinc Anode -----~
Gear Shift
Lever
Fuel Lift Pump
Oil Pressure Swi
Fresh Water Fill Cap
Lube Oil Dipstick
Fuel Injection Pump
Fresh Water
Lever
Shut-off
Lever
Oil Pressure
Sender
Lube Oil Drain Hose
5 Wes!erbeke Diesel Engines

W 12B TWO Marine Diesel Engine
Fresh Water Fill Cap Lube Oil Fill
Fresh Water
Air Bleed ---"'0
Sea Water
Pump
DC Charging
Alternator
Lube Oil Drain
Starter with Sol
Westerbeke Diesel Engines
DC
Battery Ground Connection
6
Amp DC Circuit Breaker
_Pretle"t Solenoid
gOO Exhaust Elbow
eat Exchanger
Gear Dipstick
Oil Filler
BW Marine Gear
Assembly
Adjustable Engine Isolator

W 1213 TWO MARINE DIESEL ENGINE
Engine Type
Governor
Valve Mechanism
Combustion Chamber
Bore & Stroke
Piston Displacement
Firing Order
Direction of Rotation
Maximum Torque (at 2700 rpm)
Compression Ratio
Compression Pressure
Valve Seat Angle
Valve Clearance
(engine cold)
Dimensions
Inclination
Dry Weight
Fuel Consumption
GENERAL SPECIFICATIONS
Diesel, lour-cycle, two-cylinder, fresh water cooled,
vertical, in-line (12
hp at 3600 rpm maximum)
Mechanical, centrifugal weight type
Overhead
Swirl chamber
type
2.56 x 2.68 inches (65 x 68 mm)
27.52 cubic inches (0.45 liters)
1-2
Clockwise, when viewed from the front
19 Ib-ft (2.83 kg-m)
25:1
455 psi (32 kg/cm2) at 320 rpm
Intake 450
Exhaust 450
Intake 0.0098 inches (0.25 mm)
Exhaust 0.0098 inches (0.25 mm)
Height: 19.57 inches (497.07 mm)
Width: 17.75 inches (450.85 mm)
Length: 24.90 inches (632.46 mm)
Continuous 140
Temporary 25
0 (not
to exceed 30 min.)
205 Ibs (92.9 kgs)
0.3 U.S. gph (1.14 Iph) running at
2500 rpm (approximate)
7 Westerbeke Diesel Engines

W 12B TWO SYSTEM SPECIFICATIONS
FUEL SYSTEM
Fuel
Injection Pump
Injection Timing
Nozzle
Injection Starting Pressure
Lift Pump
Fuel Filter (on engine)
Air Cleaner
Air Flow (engine combustion)
COOLING SYSTEM
General
Operating Temperature
Fresh Water Pump
Sea Water Pump
Sea Water Flow, at 3600 rpm
(measured before discharging
into exhaust elbow)
System Capacity (fresh water)
LUBRICATION SYSTEM
General
Oil Filter
Sump Capacity (includes filter)
Westerbeke Diesel Engines
Open flow, totally self-bleeding
No.2 diesel oil (cetana rating of 45 or higher)
Nippondenso (Bosch M type)
25° ± OS BTDC (Static)
Throttle type
2275.2 psi (160 kg/cm2)
12-Volt DC; lift capacity 6 ft (1.8 m)
Canister type, with replaceable element
Metal screen type -cleanable
27.0cfm (O.77cmm)
Fresh water cooled block,
thermostatically-controlled
with sea water exchanger system
170 -190° F (77 - 88° C)
Centrifugal type, metal impeller, belt-driven
Positive displacement, rubber impeller, belt-driven
gpm ( Ipm) approximate
4.0 qts (3.78 liters)
Forced lubrication by gear pump
Paper element, spin-on type
3.27 U.S. qls (3.1 liters)
8

W 128 TWO SYSTEM SPECIFICATIONS
Operating
Oil Pressure
Oil Grade
ELECTRICAL SYSTEM
Starting Battery
Battery Capacity
Starting Aid
Starter Motor
DC No-Load Current
Cold Cranking Current
Alternator
Regulator
TRANSMISSION
HBW50
BW3
Standard Gear Ratio
Optional Gear Ratio
Direction of Rotation
Lubrication Fluid
Sump Capacity
Standard Gear Ratio
Direction of Rotation
Lubricating Oil Grade
SAE Grade
Sump Capacity
35 - 55 psi (2.46 - 3.86 kglcm2)
API specification CC or CD
12-Volt, 35 A-H, (-) negative ground
(recommended)
(45 A-H cold areas)
90 - 125 (Ampere-Hours)
12-Volt sheathed type glow plug
12-Volt, 1.2KW, solenoid, actuated shift
60 Amps at 11.5 Volts (6500 rpm, min.)
209 Amps at 12 Volts
12-Volt DC, 35 Amps
Internal regulator, built into alternator
14.4 Volts DC ± 3 Volts
2:1
2.5:1
Right handed -standard transmission
Automatic Transmission Fluid (ATF)
Type Aor Dexron II
0.32 U.S. qts (0.3 liters) approximate
2.47:1
Right handed -standard transmission
API specification of CC or CD
SAE 20 or SAE 30 exclusively
0.37 U.S. qts (0.35 liters) approximate
9 Westerbeke Diesel Engines

INSTALLATION CHECKS
General
Because the crafts in which Westerbeke engines are installed vary in design, installation procedures will vary
according to your craft's specific design. It
is not the intent of this section to advise boatyards or installers
on proceduresalreadywell-developed and well-understood. However, it is importantthatthe owner/operator
realize there are details of the installation which require periodic checks to ensure the best operating condi-
tions for the equipment and safe operating conditions for the personnel on board. Proper location and in-
stallation of the diesel engine in the vessel are of prime importance.
Factors in the installation that must be considered are ventilation, to aid in cooling and to provide air for en-
gine combustion; exhaust system, to property discharge raw cooling water, quiet the exhaust and expel ex-
haust gas; cooling water supply; fuel supply; and electrical connections.
CAUTION
For safety reasons, the engine and transmission are NOT filled with lubricating oil for ship-
ment. Before leavingthe factory, however, each engine with transmission is thoroughlytested
with oil
in it. This testing, among other things, provides all internal parts with a coating of oil.
This
oil acts as a preservative, providing reliable protection against corrosion for at least one
year
if the engine and transmission are property stored.
Location
The location should be such that it is dry, and awayfrom being splashed by bilgewater or waterfrom above.
The engine should be properly ventilated and accessible for minor servicing and repairs (access
for major
repairs should be given consideration as well). The location must be propertyventilated
to provide fresh air
for engine combustion. The engine's lubrication oil sump dipstick, the fresh water and oil fills, and the
transmission's dipstick and transmission or oil fill port must be accessible.
riLL CAP
COOLANT
RECOVERY ___
COCKPIT
TANK ~
AL T!RNATIi~~~~~i=;~;:;;;===::J'7
MOUN11NC
STIlAI"
POSITIONS
CABIN
INSTALLATION ANGLE
MUST HOT EXCEED 14'
Please notethat the engine's installation angle cannot exceed 14' from the horizontal plain.
Westerbeke Diesel Engines 10

Rigging lind lilting
The engine is fitted w~h lifting eyes. Rope or chain slings capable of supporting the engine's weight should
be attached to the eyes and the engine lifted by means of tackle attached to these slings. The lifting eyes
havebeendesigned
to carrythefull weight of theengine; therefore, auxiliaryslingsare notrequired ordesired.
CAUTION
Slings must not be so short as to place signijicant sheer stress on the engine's lifting eyes.
Strain placed on the engine's lifting eyes bythe lifting sling must not be in excess of 10'from
the vertical plain.
ENGINE
SL:ING LIFTING
~HC;LE MUST NOT
EXCEEO 10·
LIFTING
EYE
The general rule in moving engines is to see that all of the equipment used is amply strong and firmly fixed
in place. Move the engine a little at atime and see that IT is firmly supported. Eliminate the possibility of ac-
cidents by avoiding haste. Do
nollift the engine by its propeller coupling, or pry against this coupling with
a crowbar, because excessive pressure of this type may distortthe coupling.
In certain situations it maybe necessary
to liftthe engine in positions otherthan the horizontal position. Cer-
lain situations exist
by which the engine must be lowered endwise through a small hatchway which cannot
be made larger. Under these conditions, if the opening
of the hatchway is extremely narrow, tt is possible
to reduce,
to some extent, the outside dimensions of the engine by removing external components such as
the alternator, the cooling system's piping, the heat exchanger, certain filters, the mounting lugs and other
obstructive equipment. This accessory equipment should be removed by a competent mechanic and spe-
cial care should be taken to avoid damagingany exposed parts. In addition, be careful not to allow dirt from
enteringanyopening created bythe removal of equipment. Parts removed should be returned totheir respec-
tive position
as soon as the engine has cleared the hatchway.
In case it becomes necessary to hoistthe engine eitherfront-end upwards or transmission-end upwards, the
attachmentofslings must be done carefullyto avoid the possibility
of damagingthe parts on whichthe weight
may bear. Special rigging work
is best done by someone experienced and competent in handling heavy
machinery.
11 Westerbeke Diesel Engines

Engine Bolts
Bronze or stainless steel hanger bolts of appropriate size are recommended for use through the engine's
flexible mounts. Less preferred are lag screws because their hold on the wood is weakened every time they
are moved, whereasthe hanger bolts stay in position. Ifthe nut on top of the hanger bolt is removed to allow
the engine to be lifted from its resting place, the hanger bolt itself remains in place as a stud. Consequent-
ly, the bond between the hanger bolt and thewood is not weakened by the removal of the nut or the engine.
Foundation for the Engine
A good engine bed contributes much toward the satisfactory operation of the engine. The engine's bed
must be rigidly constructed and neither deflect nortwist when it is subjected to the engine's weight or to the
pressures that the boat may experience while operating
in rough seas. The bed must keep the engine's
alignment within one or two thousandths of an inch of this position at all times. The bed has to withstand
the forward push
of the propeller shaft which pushes against the thrust washer bearing which finally pushes
against the engine's bolts and bed.
In fiberglass hulls, we recommend that similar wooden stringers as in wooden hulls be formed, fitted, and
then glassed securely to the hull. This allows the hanger bolts
to be installed firmly in the wood, thereby
reducing noise and transmitted vibration.
The engine support stringers must be as wide or widerthan the engine mounting isolator. Isolator overhang
and/or rounded stringer surfaces are detrimental
to the isolators' ability to retain vibration.
Preformed fiberglass engine beds, when used, should be of sufficient thickness to properly support the en-
gine and should be well-glassed to the hull when
installed.
The temptation to install the engine on a pair of
fiberglass angle irons must be resisted. Such
construction will allow engine vibration to pass
through
to the hull. Flexible mountsrequire a firm
foundation againstwhichtheymustact
if theyare
to perform their function. When possible, follow
bed design A and avoid bed design B (refer to
the illustration).
Supportsbetween the bed stringers, and extend-
ingfrom the stringers to the hull, maybe required
for propersupport and to aid in the absorption of
vibrations.
Westerbeke Diesel Engines
GOOD
A
BAD
B
Note: Avoid excessive height, use
solid stringer construction (Al.
12

Propeller Coupling
The propeller shaft coupling fitted to the transmission's output flange musttransmit not onlythe power ofthe
engine
to turn the propeller shaft and propeller, but must also transmit the thrust of the engine/transmission
either ahead or astern.
The coupling bore should be carefully machined for a slight forced fit ontothe shaft and
an accurate mating
surtace for the coupling to the output flange of the transmission.
For all engine models, a propeller half-coupling, bored to shaft size for the specific order,
is supplied. The
coupling either has a keyway with set screws or is of the clamping type.
The
fOlWard end of the propeller shaft has a long straight keyway. Any burrs should be removed from the
shaft's end. The coupling should be a lightdrive fit on the shaft and the shaft should not have
to be scraped
down or filed in order to get a fit. It is important that the key be properly fitted both to the shaft and to the
coupling. The key should fit the side of the keyway closely, but should not touch the top of the keyway in
the hub of the coupling.
If driving the coupling over the shaft
is difficult, the coupling can be expanded by heating it in a pail of boil-
ing water. The face of the propeller coupling must be exactly perpendicular to the centerline or axis of the
propeller shaft.
Propeller
The type and size of propeller varies with the gear ratio and must be selected to fit the application, based
upon boattests. To utilizethefull power
of the engine, and to achieve ideal loading conditions, usea propeller
which will permit the engine to reach its full rated RPM at full throttle while under a normal load and while it
is moving the boat fOlWard through the water. (See pages 53 and 56.)
Alignment of the Engine
The engine must be exactly aligned with the propeller shaft
in the proper fashion. No matter what material
is used to build a boat the material will be found to be flexible to some extent; hence, the boat's hull will
change its shape to a greater extent than is usually realized when the boat is launched and operated in the
water. Therefore, it becomes extremely important to check the engine's alignment at frequent intervals and
to correct any errors when they appear.
Misalignment between the engine and the propeller shaft often creates serious problems which are often
blamed on other areas suspected of causing the trouble. Misalignment will cause excessive bearing wear,
rapid shaft wear and will, in many cases, reduce the life of the boat's hull by loosening the hull's fastenings.
A bent propeller shaft will have the exact effect as those just stated; therefore, a pertectly straight propeller
shaft is absolutelynecessary. One particularly annoying result of misalignment may be leakage of transmis-
sion oil through the transmission's rear oil seal. If oil is leaking from this seal, check and make sure that the
coupling's alignment is within the limits prescribed on page 14.
Never attempta final alignment with the boat on land. The boat should be in the water and have had an op-
portunity to assume its final water form. The best time
to pertorm the propeller shaft/transmission coupling
alignment
is with the fuel and water tanks about half full and all the usual equipment on board, and after the
main mast has been stepped and the final rigging has been accomplished.
13 Westerbeke Diesel Engines

Take plenty of time in making this alignment and do
not be satisfied with anything less than perfect results.
The alignment is correct when the shaft can be easily
slipped backward and forward into the counterbore,
and when a feeler gauge indicates thaI the flanges
come together at all points. The alignment between
the propeller shaft coupling and the engine's coupling
can contain an error no greater than one thousandth
of
an inch per inch ofthe coupling diameter. For ex-
ample, if your propeller shaft coupling is three inches
in diameter, the maximum errorthaI can be allowed in
the alignment is three thousandths of an inch (.003).
In making the final check for alignment, the
engine's half coupling should
be held in one
position and the alignment with the propeller
coupling tested with the propeller coupling
in
each offour positions (A), while rotaled 90
0 be-
tween each position. This test will also check
whetherthepropeller'shalf-coupling
is in exact
alignment on its shaft. Then, keeping the
propeller coupling in one position, the align-
ment should be checked by rotating the
engine's half-coupling in
90
0 increments,
checking dimension A while
in each 90
0 posi-
tion until the half-coupling
has been rotated lull
circle.
The engine's alignment should be rechecked
after the boat has been
in service lor one 10
three weeks and, If necessary, perform the
alignment again. Usually it will be found that
the engine
is no longer in alignment. This does
not mean Ihat the work has been done im-
properly at first; rather, it means Iha! the boat
has taken sometime to take its final shape and
that the engine's bed and stringers have
probably absorbed some moisture. It may
even be necessary to realign the coupling hal-
ves again at a later time.
Weslerbeke Diesel Engines 14
.333 FEELER GAGE
PROPELLER SHAFT

Exhaust System
The exhaust system provides an outlet line to vent engine exhaust gases out of and away from the vessel.
The system also discharges sea water which has passed through the engine's sea water circuit by mixing it
with hot exhalJst gases. This mixing helps cool the exhaust gases and exhaust elbow and plumbing. The ex-
haust system and the sea water supply to the exhaust must be configured to prevent the siphoning of sea
water into the exhaustthrough the sea water cooling circuit and to prevent the entry of sea water into the ex-
haust through the circuit's thru-hull discharge port. If not prevented, sea water entering through the dis-
charge port can lill the exhaust system muffler and enter the engine's cylinders. This will prevent proper
starting and possibly cause damage to internal engine components.
The sea water supply hose
to the exhaust system water injection elbow should be routed (looped) at least
12 inchesabove thevessel water line. An anti-Siphon break should be installed, when needed, atthe top of
this loop. The
top of the loop should be placed high enough above the vessel's water line so as to remain
above the water line when the vessel
is underway, no matter what the angle of heel or roll may be.
InSUlale-;:;:~;::;;;;~;;::o7~18"
, ..
ENCINE INSTALLATIONS WITH EXHAUST MANI-
FOLD/WATER INJECTED-ELBOW MINIMUM OF 6
INCHES ABOVE VESSELWATER LINE.
-.
6·
ENGINE INSTALLATIONS WITH EXHAUST MANI-
FOLD/WATER INJECTED ELBOW AT OR BELOW
VESSEL WATER LINE
1',,' I.D.
" 2' 1.0.
48"
m"
12" mEn
The sea water supplythru-hull sea cock fittings mustbe ofthe flush-hull type. High-speed scoop type of fit-
tings should not be used as they tend to encourage siphoning.
The exhaust discharge from the water lift muffler should be routed well above the water line then downward
to the thru-hull discharge. This routing will prevent sea water entry if the thru-hull discharge fitting becomes
submerged when thevessel heels orrolls while underway, or
is subjected to following sea conditions. Refer
to the figures shown above lor recommended exhaust system installations.
15
Weslerbeke Diesel Engines

Exhaust Back-Pressure
The exhaust discharge hose must be of adequate size and
minimal run to prevent excessive exhaust back-pressure.
Exhaust back-pressure should be checked before a gener-
ator is put into service. (Refer to the illustration.) Excessive
back-pressure will affect the engine's performance.
To measure
for back-pressure, use a mercury manometer, a
pressure gauge, or a water column. A boatyard or marine
mechanic should have a manometer or a pressure gauge.
Measure back-pressure at the exhaust elbow when the en-
gine is runningat 3600 rpm. Back-pressure, as measured by
a manometer, apressuregauge, or watercolumn, should not
be over the following specifications:
NOTE: Otherpressure gaugesmaybe available to test
for exhaust back-pressure. Check with a competent
mechanic.
Refer
to the pressure specifications below.
A water column can be made by taking a clear plastic tube
and taping one end of the tube along a yardstick and fitting
the other end of the tube with a 1/4 inch NPT (National Pipe
Tap) pipe fitting.
Measure back-pressure at the exhaust elbow when the en-
gine is running at 3600 rpm.
Dimension A cannot exceed 39 inches of water.
Back pressure,
as measured by a gauge instrument, should
not exceed the following specifications:
3 inches of mercury (0.104 kg/cm2)
39 inches of water in a water column
(.099 kg/cm2 at 40
C)
22 ounces psi
1 1/2 psi
..
..
"
"
Exhaust
Elbow
n Exhaust
Mercury
Manometer
\
\
Excessive back-pressure can be caused by a small diameter exhaust hose, a small muffler, sharp bends in
the exhaust hose, improper fittings, water pockets, and a high volume of water in the exhaust system due
tothe length ofthe exhaust discharge hose. The use of elbows and fittings in the exhaust discharge hose's
routing should be limited since these will create flow restrictions and contribute
to exhaust back-pressure.
The generator's exhaust system must be separate from anyother engine's exhaust system. Dry portions
of
the exhaust system between the engine's exhaust manifold and the water injected exhaust elbow must be
insulated to hold in the heat.
Westerbeke Diesel Engines 16

Exhaust System Failures
When the engine's sea water is fed into an exhaust system so that the full stream
of this water strikes a sur-
face, erosion takes place. This erosion may cause premature failures. The properdesign of either a water
jacketed
or water injected 'Wet" exhaust system to prevent this problem requires that the sea water inlet be
positioned so thatthe enteringstream of sea waterdoes notdirectlystrike a surface. Inaddition, thevelocity
ofthe entering sea water stream should be as lowas possible, which can be achieved
by having inlet fittings
as big in diameteras possible.
The best protectionagainstexhaustsystem leaks is
to routinely inspectthe complete exhaustsystem. Check
for leaks around manifolds, gaskets, and welds. Make sure exhaust lines are not heating surrounding areas
excessively. If excessive heat is present, correct the situation immediately. If
you notice a change in the
sound
or appearance of the exhaust system, inspect the exhaust system and correct the cause.
Exhaust risers installed off the exhaust manifold should
not exceed 8 Ibs in total weight when rigidly con-
nected. Excessiveweightandvibration can result in a manifold failure and/orthe fracturing of the riser from
the manifold at Its attachment. Dry portions
of the exhaust connected to the manifold, which lay before the
waterinjected exhaust system,
MUST be properlyinsulated to retaintheexhaust heatwithin the exhaust pipe
IWARNINGI
Although diesel engine exhaust gases are not as toxic as exhaust fumes from gasoline en-
gines, carbon monoxide is present in diesel exhaust fumes in less concentration. Carbon
monoxideisa dangerousgasthat can cause unconsciousness and is potentiallylethal. Some
of the symptoms or signs of carbon monoxide inhalation or poisoning are as follows:
o Dizziness o Vomiting
o Intense Headache o MuscularTwitching
o Weakness and Sleepiness o Throbbing in Temples
If you experience any of the above symptoms, get out intofresh air immediately.
Make sure there are
no unnecessary objects suspended from any portion of the exhaust lines. Excessive
weight could cause deflection
or distortion of the lines, resulting in damage or leaks. Inspect insulated por-
tions of the exhaust system to ensure there is no deterioration of the insulation.
Oil Drain
An oil sumpdrain hose is installed on the engine with the discharge end secured by a bracket atthe front of
the engine. Oil may be drained from this hose
by removing the cap and the discharge end of the hose from
the support bracket and lowering the hose into a container. The hose cap fitting is 1/4 inch NPT (National
Pipe Tap) and can be extended,
or have a pump added, for easier removal of the old oil, if desired.
17 Westerbeke Diesel Engines

Connecting Pressure Sensing Devices 10 Oil Galleries
Oil pressure sensing devices, such as senders and switches, must not be connected to an engine's oil gal-
lery with the use of extended nipples or tees. The reason is simply that continued engine vibration causes
fatigue of the fittings used
to make such a connection. If these fittings fail, the engine loses its oil pressure
and quickly seizes.
When additional sensing devices such
as switches or sensors need to be installed that function on engine
pressure, these devices must be bulkhead-mounted and connected
to the oil gallery using an appropriate
grade of lubricatirig oil hose. Any fittings used to connect the hose to the gallery must be of steel or malle-
able iron composition. Brass must not be used for this application.
Cooling System
The engine is fresh water cooled by an engine-mounted heat exchanger. Sea water is used as the heat
exchanger's cooling medium. Sea water is pumped intothe exchanger by a sea water pump, where it cools
the fresh waterthat circulates through'the engine block,'and
is then injected into the exhaustdischarge, car-
rying with it the heat removed from the engine's fresh water cooling system.
Sea water should be supplied to the sea water pump through aflush-type hull fitting using a wire-reinforced
hose between the thru-hull fitting and the sea water pump. The sea water should be directed through a
visual-type sea water strainer, which will trap debris before it reaches the sea water pump and the heat ex-
changer, and then be delivered to the pump. Hoses routed from the thru-hull fitting to the strainer and to
the sea water pump should be wire-reinforced to prevent the hose from collapsing while the engine is run-
ning (suctionfrom the pump maycollapse anon-reinforced hose). The sea waterstrainer should be mounted
at or below the water line
to make sure the sea water line remains primed.
CAUTION
DO NOT
use a scoop-type thru-hull fitting as a means of supplying sea water to the engine.
Water pressure against this type of fitting, while the vessel
is under sail, can push sea water
past the sea water pump's impeller into the engine's exhaust system, filling
it and the engine
as well. Flush-type, clear, thru-hull fittings are recommended and should be located on the
hull so as to be below the waterline during all angles of boat operation.
The use of common-type street elbows
is not recommended for plumbing the sea water cir-
cuit. These generally have very restrictive inside diameters. Machine fittings are preferred.
Automatic Alarm System
High Water Temperature Alarm
A high water temperature alarm has been supplied with the instrument panel. If the engine's fresh water
coolant reaches 205' F (96' C), a switch located at the engine's thermostat housing area will close sound-
ing this alarm which will emIT a continuous signal. Refer to the "DESCRIPTION OF INSTRUMENT PANELS"
section of this manual for the location of the alarm in your engine panel, page 23.
Westerbeke Diesel Engines 18