Onan RDJC User manual

Service
Manual
Diesel Engines
9-84
Printed in USA.
Redistribution or publication of this document, 
by any means, is strictly prohibited.

Safety Precautions
It isrecommendedthat you readyour enginemanualand
becomethoroughly acquainted with your equipment be-
fore you start the engine.
Thissymbolls used throughoutthis
manual to warn
of posslble serious
personal Injury.
Thlssymbol
refers toposslbleequip-
ment damage.
Fuels, electrical equipment, batteries,exhaust gases and
movingpartspresentpotentialhazardsthatcouldresultin
serious, personal injury. Take care in following these
recommendedprocedures.
Safety Codes
0 All local, state and federal codesshould be consulted
andcompliedwith.
0 This engine is not designed or intended for use in
aircraft. Any such useisat theowner's solerisk.
General
Provideappropriate fireextinguishersand install them
inconvenientlocations.UseanextinguisherratedABC
by NFPA.
Makesure that all fasteners on the engine are secure
and accurately torqued. Keep guards inposition over
fans, driving belts,.etc.
If
it isnecessarytomakeadjustmentswhiletheengineis
running, use extreme caution when close to hot ex-
hausts, movingparts,etc.
ProtectAgainst Moving Parts
Do not wear loose clothing inthe vicinity of moving
parts, such as PTO shafts, flywheels, b'lowers, coup-
lings, fans, belts,etc.
Keepyour handsaway from movingparts.
Batteries
0 Beforestarting work onthe engine,disconnect batter-
iesto preventinadvertentstarting
of the engine.
DO NOT SMOKEwhile servicing batteries. Lead acid
batteriesgiveoffahighlyexplosivehydrogengaswhich
canbeignitedbyflame,electricalarcingorbysmoking.
Verifybatterypolaritybeforeconnectingbatterycables.
Connectnegativecablelast.
FuelSystem
DO NOTfillfuel tanks while engineis running.
DO NOT smoke or use an openflame inthe vicinity of
the engine or fuel tank. Internal combustion engine
fuelsare highlyflammable.
Fuellines mustbe of steel piping, adequatelysecured,
and free from leaks. Piping at the engine should be
approved flexible line.
Do not use copper piping for
flexible lines as copper will work harden and become
brittleenough to break.
Besureall fuel supplieshavea positiveshutoff valve.
.I
ExhaustSystem
Exhaust products of any internal combustion engine
are toxic andscancause injury, or death if inhaled.
All
engineapplications, especiallythosewithin aconfined
area, should be equipped with an exhaust system to
dischargegases tothe outsideatmosphere.
0 Do not useexhaust gasesto heat a,compartment.
Make sure that your exhaust system is free of leaks.
Ensurethat exhaust manifolds are secure and are not
warped bybolts unevenly torqued.
Exhaust Gas isDeadly!
Exhaustgasescontaincarbonmonoxide,apoisonousgas
that might cause unconsciousnessand death. It is an
odorlessand colorless gas formed during combustion of
hydrocarbon fuels. Symptoms of carbon monoxide poi-
soningare:
Headache 0 MuscularTwitching
WeaknessandSleepiness
Ifyouexperienceanyofthesesymptoms,getoutintofresh
air immediately,shut downthe unitand do not use until it
has been inspected.
Thebest protectionagainstcarbonmonoxideinhalationis
properinstallation andregular,frequentinspectionsof the
complete exhaust system.
If you notice a change in the
soundorappearanceofexhaustsystem, shuttheunitdown
immediatelyandhave
it inspectedandrepairedatoncebya
competentmechanic. n
'CoolingSystem
Coolants under pressure have a higher boiling point
thanwater.
DO NOTopenaradiatorpressurecapwhen
coolant temperature is above 212°F (100OC) or while
engineisrunning.
Dizziness
0 'Vomiting
0 Throbbing inTemples
Keep the Unitand SurroundingArea Clean
Make sure that oily rags are not left on or near the
engine.
Remove all unnecessarygrease and oil from the unit.
Accumulatedgreaseandoilcancauseoverheatingand
subsequentenginedamageandpresent
a potentialfire
hazard.
. E-4
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by any means, is strictly prohibited.

.
Table of Contents
TITLE
PAGE
General Information .................................................... 2
Specifications ......................................................... 3
Dimensionsand Clearances
............................................ 4.
Assembly Torques and SpecialTools
.................................... 6
EngineTroubleshooting
................................................ 7
Service and Maintenance ............................................... 8
Exhaust System ....................................................... 14
CoolingSystem ....................................................... 16
Fuel System
.......................................................... 22
Oil System ........................................................... 36
Governor System ..................................................... 39
StartingSystem
....................................................... 41
Engine Disassembly ................................................... 48
ControlSystem
....................................................... 59
INCORRECT SERVICE OR REPLACEMENT OF PARTS MIGHT RESULT IN
SEVERE PERSONNAL INJURY AND/OR EQUIPMENT DAMAGE
. SERVICE
PERSONNEL MUST BE QUALIFIED
TO PERFORM ELECTRICAL AND/OR
MECHANlCAL SERVICE
.
1
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by any means, is strictly prohibited.

General Information
INTRODUCTION
Thismanualdealswithspecific mechanicalandelec-
trical information needed by engine mechanics for
troubleshooting, servi,cing,repairing,or overhauling
the engine.
Usethe table of contentsfor aquick referencetothe
separateengine system sections.
Use the separate parts catalogs, available at the
dealer level, for partsidentificationandfor establish-
ingtheir proper location on assemblies.
The troubleshooting guide is provided as a quick
referencefor locating and correcting enginetrouble.
The illustrations and procedures presented in each
section apply tothe engines listedonthecover.The
flywheel end of the engine is the front end,
so right
and left sides are determined by viewing the engine
from the front.
The disassembly section contains major overhaul
procedures for step by step removal, disassembly,
inspection, repair, and assembly of the engine
components.
Ifamajorrepairpranoverhaulisnecessary,acompe-
tent.mechanic should either do the job or supervise
and check the work of the mechanic assignedto
do
thejobtoensurethatalldimensions, clearances,and
torque values arewithin the specifiedtolerances.
The wiring diagram on the last page of the manual
shows how the electrical components are inter-
connected.
Apartscatalog (availableatthedealerlevel)contains
detailed exploded views of each assembly, the indi-
vidual piece part numbers, and their proper names,
for ordering replacement parts.
.
Useonly GenuineOnanreplacementpartsto ensure
quality and the best possible repair and overhaul
results. When ordering parts, always use the com-
plete Model and Spec number as well as the Serial
number shown onthe nameplate.
ENGINE MODEL REFERENCE
Identify your model by referringto the MODEL and
SPEC (specification)
NO. as shown on the unit
nameplate. Always use this number and the engine
serialnumberwhenmakingreferencetoyourengine.
Howtointerpret
MODEL and SPEC NO. ongenerator
set engines.
<
1 2 34
1. Factorycodefor generalidentification purposes.
2. SpecificTYPE, as follows.
R - REMOTE type. Electric starting. Optional
accessoryequipment can beconnectedfor
2
wire remote control of starting and stopping.
Atwo
(2) wire automatic linetransfercontrol
is availablefor standby service.
E
- ELECTRICstart type. Electric starting at the
plant only.
3. Factory code for specific optional equipment
4. Specification (Spec Letter). Advances with fac-
Howtointerpret
MODEL and SPEC NO. onindustrial
engines.
supplied.
tory production modifications.
1. 4.5
1
1. Factorycodefor general identification purposes.
2. StarterTYPE, as follows:
M-ELECTRICstarttype.
S-MANUAL start type.
3. PTOTYPE, as follows:
F - CLUTCH
A
- STUB SHAFT
4. Factory code for specific optional equipment
5. Specification (Spec Letter). Advances with fac-
supplied.
tory production modifications.
2
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Specifications
~~ ~
All dimemsionsin U.S. customaryunits of measure (metric inparentheses) unlessotherwise specified.
~ SERIES
UNIT OF
SPECIFICATION MEASURE RDJC RDJF
Number of Cylinders 4 4
Diesel Fuel ASTM2-D ASTM2-D
Bore in 3.250 3.500
(mm) (82.55) (88.90)
Stroke
in
3.625 3.625
(mm) (92.08) (92.08)
Displacement cu in 120 140
(litre) (2.0) (2.3)
Compression Ratio 19.0 to
1 19.0 to 1
FiringOrder 1-2-4-3 1-2-4-3
Crankshaft Rotation
Governor Adjustable Mechanical
Valve Clearance (Cold)
(viewedfrom flywheel) Clockwise Clockwise
Intake in 0.01
1 0.01 7
(mm)
(0.279) (0.432)
Exhaust
in 0.016 0.01 7
(mm) (0.406) (0.432)
Oil Filter Full Flow FullFlow
CrankcaseCapacity Qt 6.5 6.5
withfilter change (litre) (6.15) (6.15)
Battery Requirements:.
AmbientTemp. Quantity
Range Required
warmer 2
32"Fand
0" Fand
warmer 2
-25Oand
warmer
Voltage BCI Group CrankingPerf. Amp Hr Cap
Size (Amps) at 0°F
(20 Hr. Rate)
6 2 565 135
6 5D
800
1080
190
222
3
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Dimensions and Clearances
All clearances givenat roomtemperature of 70' F (21'C) .
Ail dimensions ininches(mililmetres in parentheses) unlessotherwisespecified.
CAMSHAFT .
BearingJournal Diameter. Front ......................................... 2.2500-2.2505(57.150-57.163)
BearingJournal Diameter. Center ........................................ .. I .2580.1.2582 (31.953-31.958)
BearingJournal Diameter. Rear ...................... .' .................... 1 . 1875-1 . I880 (30.163-30.175)
BearingClearance Limit (0 rig i nal) .............................................. .0015-.0030 (.038-.076)
BearingClearance Limit (Replacement) .......................................... .0012-.0049 (.030-.123)
EndPlay ............................................................................ .007-.039 (0.2-1.0)
CamTappet.Diameter (RDJC Priorto Spec P) ................................ .7475-.7480 (18.987-18.999)
CamTappet Hole Diameter (RDJC Prior to Spec P) ........................... .7507.. 7515 (19.068-19.088)
CamTappet Hole Diameter (RDJF. RDJCBeginSpec P) ...................... .8755-.8765 (22.238-22.263)
LargeBore Diameter .................................................. 2.1871-2.1876(55.5523-55.5650)
Small Bore Diameter ...................................................... 1.043-1.045(26.4922-26.543)
Large Bearing Boreto Small Bearing Bore
(Center-to-Center)
................................................... 5.998-6.002(152.3492-152.4508)
Connecting Rod End Play ............................................................ .002-.016 (.05-.41)
Bore Honed Diameter ..................................................... 3.2495-3.2505(82.537-82.563)
MaximumAllowable Taper ................................................. : .............. 1 0.005 (0.127)
MaximumAllowable Out-of-Round .......................................................... 0.001 (0.025)
Main BearingJournal Diameter .......................................... 2.2427-2.2435(56.965-56.985)
Front and Rear Main BearingClearance (Original) ................................ .0030-.0043 (.076-.109)
Center Main Bearing Clearance (Original) ....................................... .0024-.0052 (.061-.132)
Front and Rear Main BearingClearance (Replacement) ............................. .0024-.0062 (.06-.16)
Center Main BearingClearance (Replacement) ................................... .0024-.0052 (.061 -;I 32)
Connecting RodJournal Diameter ......................................... 2.0597-2.0605(52.316-52.337)
Rod BearingClearance .......................................................... .001-.0033 (.025-.084)
EndPlay ......................................................................... .010-.015 (.254-.381)
Clearance in Cylinder
Measure
90" to pin.just below oil ring ............................................ .0055-. 0075 (.140-.191)
RingGrooveWidth
Cam Tappet Diameter (RDJF. RDJC BeginSpec P)
........................... .8725.. 8730 (22.162-22.174)
CONNECTING RODS
CY LlNDER
CRANKSHAFT
PISTONSAND RINGS
TOP ...................................... i ................................
NO . 2 ......................................................................
NO . 3 ......................................................................
NO . 4 ......................................................................
.0970.. 0980 (2.464-2.489)
.0965-.0975 (2.451-2.477)
.0965.. 0975 (2.451-2.477)
.1880-.1897 (4.775-4.818)
Ring Gap ........................................................................... .010-.020 (.25-.51)
Clearance in Piston .................................................................... Thumb Push Fit
Connecting Rod Bushing Clearance
............................................. .0002-.0007 (.005-.Ol8)
Rotation ........................................................................... Counterclockwise
Pinion Clearanceto PinionStop (Solenoid Plunger Bottomed)
...................... .070-.120 (1.78-3.05)
Armature End Play ............................................................... .005-. 030 (.030-.760)
PISTONPIN
STARTING MOTOR
(Prestolite)
c
4
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VALVE-I NTAKE
StemDiameter (Stemistapered)
**Center
..................................................................... .3401--3411 (8.639-8.664)
**Face
....................................................................... -3386-.3396 (8.601-8.626)
Valve Face..
..................................................................................... 42"
Guide Clearance
......................................... i ..................... .0015--0030 (.038-.076)
Stem Diameter
............................................................... .3405-.3415 (8.649-8.674)
Guide Clearance
............................................................... .0030-.0050 (.076--127)
Valve Face..
..................................................................................... 45"
Length
.............................................................................. 1.7812 (45.2424)
Outside Diameter
....................................................... .4690-.4695 (11.9126-11.9253)
InsideDiameter (after reaming)
Exhaust
................................................................... .3445-.3455 (8.750-8.776)
Intake
..................................................................... .3425-.3435 (8.700-8.725)
Cylinder Block BoreDiameter..
............................................. .467-.468 (11.8618-11.8872)
Bore Diameter
............................................................. 1.361-1.362 (34.570-34.595)
Insert OutsideDiameter
................................................. 1.364-1.365 (34.6456-34.6710)
Seat Width..
..................................................................... .047-.062 (1.19-1.57)
Angle..
.......................................................................................... 45'
Available Insert Oversizes
.................................................................. .002 (.0508)
VALVE-EXH AUST
VALVE
GUIDE
VALVE SEATS
-005 (.127)
.010 (.254)
.025 (.635)
VALVE SPRINGS
Load-Valve Closed ............................................................. 45-49 Ib(200-218 N*)
Load-Valve Open (RDJC PriortoSpec P) ........................................ 83-93 Ib(369-414 N*)
Load-Valve Open (RDJF, RDJC Begin Spec P) ................................... 87-97 Ib(388-432 N*)
*N. Base unit, Newtons. Unit of force.
**Measure intakevalve stemat points indicated.
Valve Stem Diameter
(Intake)
-- FACE
2.96 in
(75.2 mm) CENTER
1.18 in
5
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Assembly Torques and Special Tools
The assembly torques given here will assure proper
tightness without danger of stripping threads. If a
torquewrench isnotavailable, estimate thedegree
of
tightness necessary for the stud, nut, or screw. Be
careful nottostripthreads. Usereasonableforceonly
and a wrench of normal length.
Specially designed place bolts do not require a
lockwasher or gasket. Do not attempt to use a
lockwasher with these bolts; it will defeat their
purpose. Check allstuds, nutsandscrews often, and
tighten as needed to keep them from working loose.
S.PECIA.L TOOLS
These tools are available from Onan to aid service
and repair work.
Diesel Nozzle Tester
.................... 420-0184
Diesel Pintle Nozzle Cleaning Tool
Set (includesinjection nozzle
centering tool)
........................ 420-0208
Driver, Center Camshaft Bearing
(RDJFonly)
.......................... 420-0254
Driver, Valve Seat ....................... 420-0270
Oil Seal Guide and Driver.. .............. 420-0250
Wrench, Oil Filter (for Purolator
full flow filter).
........................ 420-0268
Nozzle Centering Sleeve. ................ 420-0321
Delivery Valve Test Fixture .............. 420-0322
Combination Main and Cam
Bearing Driver
........................ 420-0326
Diesel Compression Tester .............. 420-0283
Valve Spring Compressor Tool ........... 420-0119
Valve Seat Remover ..................... 420-0311
Flywheel Puller ......................... 420-0100
Crankshaft Gear Puller .................. 420-0072
Crankshaft Gear Pulling Ring ............ 420-0248
Tool Catalog ........................... 900-0019
TO RQ U E SPEC I F I CAT1 0 NS
Center main bolt (4 cylinder). ...
Ft.-Lb. Nom
97-102(131-138)
Connecting rod bolt ............ 27-29 (37-39)
Exhaust manifold nuts .......... 13-15* (18-20)
Flywheel mounting screw ....... 65-70 (88-95)
Fuel pump mounting screws .... 15-20 (20-27)
Gear case cover ................ 18-20 (24-27)
Glow plug.. .................... 10-15 (18-20)
Injection nozzle mounting
screws
....................... 20-21 (27-28)
Injection pump mounting
screws
....................... 15-16 (20-22)
Intake manifold. ................ 13-15 (18-20)
Oil base mounting screws.. ..... 45-50 (61-68) .
Oil Filter .......... Handtight plus 1/4 to 1/2 turn
Oil pump mounting screws.. .... 15-20 (20-27)
Rear bearing plate. ............. 40-45 (54-61)
Rocker arm nut.. ............... 4-lo** (5-13)
Rocker arm stud.. .............. 35-40 (48-54)
Rocker-Box cover .............. 8-10 (11-14)
Cylinder head bolt. ............. 44-46 (60-62)
..
* - Exhaust nuts must be tightened evenly.
** - This torque is due to friction between the threads
only and
locks the nuts in place. Use the rocker
I
arm nut to adjust valve lash.
.5
6
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Engine Troubleshooting
e Incorrect Timing
0 Pow Quality Fuel
Dirw Fuel Filters
e 0
Restricted Air Intake -Dirty Air Filter
0
0
Our of Fuel or Shut Off Closed
Worn or Damged Transfer Pump. Leaking Diaphragm
0 Faulty Injection Pump. Nozzles or Garters
e Fuel Line Leaks
Wrcq Timing Button inInjection Pump
Wrong Thickness Pump Mounting Gaskets
Run For Long Periods of Tlmc at NO LOAD
Loose or Disconnected Linkage
Binding Linkage
Exccrrive Wear in Linkage
Incorrect Governor Adjustment
High Spring Sensitivity
Incorrectly Installed Governor Yoke 01 Cup
lnrufflclent Coolanl
FauIw Thermosrat
, .. ~. ~~~ ~
Warn Water Pump or Defective Seals
Water Passages Restrimed
Blawn Head Gasket
Ovcrhratinm
- - .
Restricted 01 Too Long Water Liner
Defective Expansion Tank Pressure Cap
Inadequate Air Circulation
Poor Compression
Loose Piston
Loose Conncctmg Rod or Crankshaft Bearing
lncorreci Valve Clearance
Broken 01 Weak Valve Same
.-
High Exhaust Back Pressure
Valves Not Seating Properly
worn Bearings
Worn Cylinder Walls. Pistmr. Rings
Stickinz Valves
Wwn nr Dwry Valve Guides
7
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Service and Maintenance
PRE-STARTING
Preparations for the initial and each additional star-
ting operation should include careful checks of the
oil, fuel, cooling, and electrical systems.
Before engine is put in operation, check all com-
ponents for mechanical security. If an abnormal
condition, defective part, or operating difficulty is
detected, repair or service as required. The engine
should bekeptfree of dust, dirt, andspilledoilorfuel.
Be sure proper operating procedure is followed.
Crankcase Oil
Multi-grade oils (such as 5W-30) are recommended
for service in ambient temperatures of 32OF. and
colder. OnOnan
J Diesel liquidcooled engines, SAE
15W-40or20W-40oils (CD/SE Service Designation)
maybeusedinanambienttemperature rangeof
15" F
(-10°C) through 90°F (32°C). Refer to the oil chart
below for recommended viscosity grades at various
temperature ambients.
I I I
1
I I
0 20 . 40 ' 60 80 100
-2b -10 0 10 -20 30 40
ERATURERANGE YOU EXPECT BEFORE NEXT OIL CHANGE
UseoilwithanAPIclassification of CD/SE (allviscos-
ity grades) or CC/SE (grades 1OW-30, 1OW-40, or
5W-30 only).
Whenaddingoilbetweenoilchanges, it is preferable
to use the same brand, as various brands of oil may
not be compatible together. Refer to the Operator
and Service Maintenance Schedule on page
11 for
recommended
oil change intervals and procedures.
WARNING
Crankcasepressure couldblow out
m hot oiland cause serious burns. Do
NOT check oil while the engineis operating.
Recommended Fuel
Use ASTM 2-D or 1-D fuel with a minimum Cetane
number of 45*. Number 2 diesel fuel gives the best
economy for most operating conditions; however,
use ASTM 1-D fuel during the following conditions:
1. When ambient temperatures are below 32OF
2. During long periods of light engine load; or no
(0" C);
load.
"NOTE:FuelswithCetanenumbershigherthan 45 maybeneeded
in higher altitudesor when extremely low ambient temperatures
are encounteredto prevent misfires.
Uselowsulfurcontentfuel havingapourpoint(ability
to filter) of at least 10" below the lowest expected
temperature. Keepthe fuel clean and protected from
adverse weather. Leave some room for expansion
when filling the fuel tank.
Due to theprecise tolerancesof die-
sei injectionsystems, it
is extremely
important that thefuel be kept clean. Dirt in the
sys-
tem can cause severe damage to both the injection
pump and the Injection nozzles.
WORK TRANSFER PUMP
PRIMING LEVER UNTIL
FUELFLOWS FROM
RETURN LINE FITTING
OF INlECTlON PUMP.
FIGURE 1. BLEED FUEL SYSTEM
If the camshaft pump lobe is up, crank engine one revolutionto
permit hand priming.When finished, returnpriming lever inward
(disengagedposition) to permit normal pump operation.
8
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Bleeding Fuel System
Bleedairfromfuelsystemasfollows: Disconnectfuel
returnline, Figure
1- Operate hand priming lever on
fueltransfer pumpuntilfuel flowingfromfuel return
line is free of air bubbles. Then reconnect the fuel
return line.
PRE-HEATING AND STARTING
BEFORE STARTING: CHECK FUEL SUPPLY.
BE SURE SHUTOFF VALVES ARE OPEN.
.
I
I
PRIME FUELSYSTEM IF FUELFILTERSWERE DRAINED OR CHANGED.
SYSTEM WAS JUST INSTALLED. FUEL TANK RAN
DRY.
--
TO PRIME FUEL SYSTEM:
MOVEPRIMINGLEVERUP
AND DOWN UNTIL FUEL
FLOWS STEADILY FROM
NECTED).
RETURN LINE (DISCON-
?*
- FUEL FILTERS
FUEL TRANSFER
PUMP
PRIMING LEVER
FUEL RETURN LINE
Preheating for 60 seconds is recommended on all
DJ-Series Diesels at
55°F (13°C) or lower, and 30
seconds for temperatures above 55" F (13°C). Refer
toOnanDieselstartingGuide, foradditional starting
guidelines.
inhalation of exhaust gases might
i resuit in seriouspersonal injury or
death. Be sure deadly exhaust gas is piped outside
and away from windows, doors, or other inlets to
building.
-_ -
WARNING
Useof etheras a starting aid might
cause an explosion resulting in
severe personal injury and engine damage.
Do not
use ether as a starting aid; heat or compression or
heatfromtheglowplugsmay causeasuddenignition
of theether vapor.
1. Engage PREHEAT switch for the time period
recommended below:
30 seconds ifabove 55OF (13°C) -
60 seconds if below 55°F (13°C).
2. EngageSTART switch while continuingpreheat.
3. If engine fails to start in 15-20 seconds, repeat
Holduntilengine comes upto speed.
To START:
4.
5.
1.
2.
PREHEAT COLD ENGINEPUSH PREHEATSWITCH AND HOLD -
30 SECONDS IF ABOVE 55-F (13 C):
60 SECONDS IF BELOW 55.F (13°C).
NEVER PREHEAT MORE THAN
60 SECONDS.
steps 1 & 2- Absenceof blueexhaustsmokedur-
ing cranking indicates no fuel being delivered.
Determinecause.
In extreme cold it may be necessary to maintain
preheating upto
2 minutesaftertheenginestarts
to obtain firing or to smooth out all cylinders,
especially at no load or light loads.
To prevent heater burnout and
conservebaftery,donotexceed
theoneminutepreheat periods. Longerpreheat-
ingtimeprior tocrankingtheenginecanruinthe
manifold heaterandglowplugs becausethereis
no incoming air flow to cool them. Additional
operation of the preheaters for a few seconds
duringcrankingincoldweathermay helptopre-
heat the incoming combustion air and prevent
misfires as theenginestarts running.
Verify thatoilpressuregaugereadsatleast 20 psi
after engine reachesspeed (pressure relief valve
is not adjustable).
Do notapply overvoltageto the
starting circuit at any time.
Overvoltage will destroy the glow plugs and air
heater.
if it becomes necessary to use an addi-
tional source of power tostart theset, usea
72
volt battery connectedinparallel.
STOPPING
Pushfuel solenoid switch toStop position.
Releaseswitchwhen setstops. Ifstopcircuit fails,
close fuel valve.
CAUT,ON
IFENGINEFIRES BUTDOESNOTSTART.REPEATABOVEPROCEDURES.INCLUDING
PREHEAT. LIMIT CRANKING
TO 15 TO 20 SECONDS TO CONSERVE BATTERY. IF
ENGINESTILL DOESNOTSTART. SEE-IF ENGINEFAILSTO STARTINFORMATION.
<
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IF ENGINE FAILS TO START:
KEEP ENTIRE FUEL SYSTEM CLEAN AND FREEFROM WATER
DIESEL INJECTION
PUMPS WILL FAIL IF SYSTEM CLEANLINESS IS NEGLECTED
INJECTIONPUMPS AND NOZZLES ARE NOT FIELD REPAIRABLE
BLUE-WHITE EXHAUST SMOKE:
ENGINE
IS GETTING FUEL LITTLE
OR NO EXHAUST SMOKE ENGINE IS NOT GETTING FUEL.
PRIME FUEL SYSTEM. OBSERVEFUEL FLOW FROM RETURNLINE.
.
1
I
8-79 98-4006
I
1
I
FUEL FLOWS STEADILY LITTLE OR NO FUEL FLOW
I
IF ENGINE IS STILL NOT GElTlNGFUEL, CHECK TRANSFER PUMP
1. CRANK ENGINE AND OBSERVE FUEL FLOW FROM RETURNLINE.
2. IFFUEL DOES NOT SPURT OUT. PUMP MAY BE DEFECTIVE.
I
CHECK PREHEAT SYSTEM:
1. OBSERVE AIR HEATER
THRU AIR INLET.
2. ENGAGE PREHEAT.
3. IFHEATERELEMENTDOES
NOT GLOW RED WITHIN
30 SECONDS. CHECK AIR
HEATERAND GLOW PLUG
WIRING:
CONNECTIONS TIGHT?
FREE FROM CORROSION?
II
I
CHECK FUEL SOLENOID:
I
CLOGGED FUEL FILTERS?
ON. IF NOT. CHECK FOR
BINDING LINKAGE
SOLENOID ROD
-THROTTLE ARM I I
IF ENGINE STILL DOES NOT START. CONTACT AUTHORIZED ONAN SERVICE REPRESENTATIVE
AUTOMATIC STARTING AND STOPPING
Optional controls may be used for automatic start
andstop, but must provideengine preheating.
Theautomaticcontrolshouldhave
a timedelay relay
to preheat glow plugs and the manifoldheater for at
least
20 seconds before cranking occurs. The time
delay relay prevents immediate engagement of the
starterincasetheloadisreappliedbeforetheengine
stops.
APPLYING LOAD
If practicable, allow engine to warm up before con-
nectingaheavyload.Continuousoverloadingcauses
high operating temperatures that can damage the
engine.Theexhaustsystem mayform carbon depos-
its during operation at light loads; apply full load
occasionally beforeshut-down to prevent excessive
carbon accumulations.
Try to apply the load in steps instead of full load at
one time.
BREAK-IN PROCEDURE
The unit should be run inthe following sequence:
1. One half hour at l/2 load.
2. One half hourat 3/4 load.
3. Full load.
Continuous running under one half load during the
firstfew hundredhoursmay resultinpoorpistonring
seating, causing higherthan normaloilconsumption
and blowby.
Drain and replace the crankcaseoil after first 50 hours of opera-
tion; drainwhile the engine
is stillhot.
INSPECTION
Check for alignment of engine and load. Misalign-
mentwillcauseexcessivevibrationandbearingwear.
Makeavisual inspection of the entire installation.
Contact with rotating machinery
might causeseriouspersonal injury
or death. Stay clear of rotating components and
ensurethatprotectiveshieldsandguards are inplace
and secured before operatingmachinery.
10
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VENT1LATlO N
Goodventilation isneededtocooltheengineandto
supportcombustion. Avoid recirculation ofventilat-
ing air.
HOURS OF
OPERATION
Inhalation of exhaust gases might
result in serious personal injury or
death.
Do not use exhaust heat to warm a room,,
compartment or storage area.
MAINTENANCETASK
EXHAUST
Pipeexhaust gas outsideany enclosure: exhaust gas
ispoisonous. Exhaust pipes must notterminate near
inletvents. Avoid sharp bends.Usesweeping, large-
radius elbows. Use a section of seamless, flexible
tubingbetween theengineand any rigidpipeto res-
trict vibration.
500
600
2000
3000
5000
BATTERIES
Check the condition of the starting batteries at least
every twoweeks. Seethat connections are clean and
tight. A light coating of non-conductive grease will
retard corrosion at terminals. Keeptheelectrolyte at
the proper level above the plates by adding distilled
water. Check specific gravity; recharge if below
1.260.
rn Check battery condition
Clean breather standpipes
rn Check start-disconnect circuit
Check valve clearances
Change primary fuel filter
Grindvalves (if required)
rn Clean holes inrocker box
oil lineorifices
Check nozzlespray pattern,
see Note
2
Change secondary fuel filter
General overhaul (if required) .
see Note 3
DUSTAND DIRT
1. Keep inlet screen free of dirt, etc.
2. Service air cleaner as frequently as necessary.
3. Change crankcase oil every
50 operating hours.
4. Keep oil and fuel indust-tight containers.
5. Keep governor linkage clean.
HIGHALTITUDE
Maximum power will be reduced approximately 4
percent for each 1000 feet (310 m) above sea level,
after thefirst 1000feet (310 m).
LOWTEMPERATURES
1. Use correct SAE No. oil for temperature condi-
tions. Changeoilonly when engineiswarm. Ifan
unexpected temperature drop causes an emer-
gency, move engine to a warm location or apply
heatedair (neveruseopenflame) externally
until
oilflows freely.
2. Usefresh fuel. Protect against moisture conden-
sation.
3. Keep fuel system clean, and batteries in a well
charged condition.
4. Useadditional preheat cycles duringcoldstarts.
Do not exceed one minute preheat
periods; longer periods can burn
out the heater elements.
OPERATOR AND SERVICE MAINTENANCESCHEDULE
conditions) 1. .
100 I Clean governor linkage
Change crankcase oiT
Drainfuel condensation traps
inlinesand filters,
I seeNote1
200 I Replaceoil filter
NOTE 1. Water or foreign material infuel can ruin the injection
system.
If daily inspection shows water or excessive
dirt insediment bowlfuel, handling and storing facili-
ties should be checked and situation corrected. Prim-
ary andsecondary fuel filters must be replacedfollow-
ingcorrectionof fuel contamination problem.
2. Thisservicemust beconductedbytraineddieselinjec-
tion equipment personnel with suitable test facilities.
Omit this service until these conditions can be met.
3. Tightenheadboltsandadjustvalveclearanceafterfirst
50 hours on an overhauled engine.
11
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OIL FILTER CHANGE
Place pan under old filter and remove by turning
counterclockwise. Cleanfilter mountingarea. Lubri-
cate gasket on new filter with oil and screw filter on
clockwise untilgasket touches mounting base, then
tighten 1/2 turn.
OIL DRAIN EXTENSION
Forservice convenience, install ashort (lessthan 10
inches [254 mm]) oil drain extension made from
standardpipeandfittings,
in the1/2-inch (12.70 mm)
pipe-tapped oil drain hole
in the base.
Crankcasepressure couid.biow out
hot oiland causeserious burns. Do
NOT check oil while the engine is operating.
CAP AND OIL LEVEL
HIS LEVEL
OPERATE ENGINE
ITHOIL BELOW
THIS LEVEL
OILLEVEL INDICA'TOR'
FUEL PUMP
i. ,.-\
FUEL TRANSFER PUMP
CRANKCASE
BREATHER
PIPE
INSERTA SOFT
WIRE THROUGH
BREATHER PIPE
TO CLEAN
W .BREATHERSYSTEM
BALL
JOINT
I NL.ET OUTL.ET
ONDARY
FILTER FILTER
DUAL FUEL FILTER SYSTEM
FIGURE
2. MAINTENANCE PROCEDURES
12
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OUT-OF-SERVICE PROTECTION
Thenatural lubricating qualities of No. 2 dieselfuel
should protect a diesel engine for at least 30-days
when unitisnotinservice.Toprotectanenginethat
will beoutof servicefor morethan30days, proceed
asfollows:
Returning a Unit to Service
1. Remove cover and all protective wrapping. Re-
moveplugfrom exhaustoutlet.
2. Checkwarning tagonoilbaseandverifythat oil
viscosity isstillcorrectfor existing ambienttem-
Derature.
1.
2.
3.
4.
5.
6.
7.
8.
Runengineuntilthoroughlywarm; under at least.
50 percent load.
Shut down engine and drain oil base while still
warm. Refilland attach awarning tag indicating
viscosity of oil used.
Removeglow plugs. Pourl-ounceof rust inhibi-
tor (or SAE #10
oil) into each cylinder. Install
To distribute oil in cylinder,
crank (or turn over) engineby
hand. Startercrankingis too fast; oil or inhibitor
fiuid will fire
if cranked with starter at normal
room temperature.
Serviceair cleaner per MaintenanceSchedule.
Cleanthrottle and governor linkageand protect
bywrapping with a clean cloth.
Plugexhaustoutletstoprevententranceof mois-
ture, bugs,dirt, etc.
Cleanandwipeentireunit. Coatpartssusceptible
to rustwith a light coat of greaseor oil.
Disconnect battery and follow standard battery
storage procedure.
glow plugs.
3. Clean and check battery. Measurespecific grav-
ity(1
-260 at 77" F [25OC]) andverify levelisatsplit
ring.Ifspecificgravityislow,chargeuntilcorrect
value is obtained. If level is low, add distilled
water andchargeuntilspecific gravity iscorrect.
DO NOT OVERCHARGE.
lgnition of explosive battery
gases might cause severe per-
sonalinjury. Donotsmokewhileservicingbatter-
ies.
4. Checkthatfuelinjectorsandfuel linesaresecure
and correctly torqued.
5. Clean heat exchanger.
6. Connect batteries.
7. Verify that no loads are connected to engine.
71 lnhalation of exhaust gases
mightresultinseriouspersonal
injury or death. Be sure deadiy exhaust gas is
pipedoutsideandaway fromwindows,doors, or
otherinlets to building.
8. Start engine.
Afterenginehasstarted,excessiveamount of bluesmoke will
be exhausted untilthe rustinhibitor or oilhas burnedaway.
Accidental starting of the engine
might cause severe personal injury
or death. Disconnectthebattery cablewhenrepairs
are madeto theengine, controls, or generator.
13
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Exhaust System
GENERAL
The exhaust system must efficiently expel all engine
combustion productsand muffleexhaust noiseswith
minimum back pressure. Ifback pressure istoo high,
the volumetric efficiency of the engine is reduced,
fuel economy drops, exhaust temperature increases,
and valve life is shortened.
Back pressure must not exceed 27 inches
(686 mm)
of water column for the rated load when measured
withamanometerattheexhaust manifold, Figure
3.
.Ill .....
INCHES OF
WATER
INCHES OF
MERCURY
OUNCES
FIGURE 3.
BACK PRESSURETEST WITH MANOMETER
Inhalation of exhaust gases might
result in serious personal injury or
death. Inspect exhaust system audibly and visually
for leaks daily. Repair any leaks immediately.
INSTALLATION TIPS
Points to remember when installing an exhaust
system are:
Exhaustpipesshould beas short as possiblewith
a minimum of fittings.
The muffler must be as close to the engine as
possible. Mufflers which are too far from the
manifold remain cooland collect carbon residue.
Pitch exhaust pipeupward from exhaust outlets
toavoidentrapment of rawdieselfumes inmuffler
at shutdown.
Avoid sharp bends by using large radius elbow.
Check back pressure with a mercury or water
column type manometer.
Position theexhaust outlet awayfromtheengine
air intake.
Exhaust noise can be suppressed or reduced by:
Using a heavy duty exhaust system with a more
efficient muffler.
Installing a deflector at the exhaust outlet to
direct exhaust toward theground, butawayfrom
the operator.
Using a resonator in addition to a muffler.
, Avoiding use of flexible lines.
The importance of exhaust systems (normally
supplied by the customer) cannot be over-
emphasized.
A poor or clogged system causes low
Exhaust Smoke
A lightgrayorlightbluesmokemaybearesultof low power, overheating and engine damage. A poor
ambient temperature and light load. This smoke is exhaust system increases back pressure which
unburnedfuel (not harmful totheengine) anddisap- reduces efficiency.
pearswhen more load isapplied.
Black smoke indicates overfueling (more fuel than
oxygen) and is usually caused by overloading. The
smoke or unburned fuel becomes carbon when
raisedto a hightemperature. Carbon contributes to
enginedamage because
it contaminatesthelubricat-
ingoil.
Inhalation of exhaust gases might
LiIl result In serlous personal Injury or
death.
Do not use exhaust heat to warm a room,
compartment,or storagearea.
Vent exhaust gases outside. Useflexible tubing only
between the engine exhaust outlet and rigid piping.
WARNING
If the manufacturer tailors his own
exhaust system, an Onan applica-
tionsengineer must approve the installationfor war-
ranty purposes.
INDOOR INSTALLATIONS
Locate exhaust outlet far from air inlet to avoid
recirculation. The engine exhaust istapped for 1-1/2
inchthread. Useflexibletubingtoconnecttheengine
exhaust to rigid pipe or muffler. Shield the line if
it
passesthrougha combustiblewall (Figure 4). lfturns
are necessary, usesweeping (large radius) elbows. If
pitchedupward, installacondensationtrap atpointof
rise, Figure
5.
14
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As the exhaust pipe length and number of bends
increases, largerpipe isrequiredto eliminate exces-
sive exhaust restriction and back pressure.
PIPESIZE (INCHES)
LENGTH INFEET
AND METRES
(1.5-Inch Muffler)
LENGTH INFEET
AND METRES
(2-Inch Muffler)
The chart below shows the maximum equivalent
exhaust pipelength for exhaust systems using
1-1/2
through 3 inch pipe. Also shown are the equivalent
lengths of various pipe fittings.The
TOTAL exhaust
system equivalent length (including all fittings and
muffler) should not exceed the length shown in the
chart for the size of pipe used. Use a manometer to
verify that back pressuredoes not exceed
27 inches
(686 rnm) H20.
1.5 1.75 2.0 2.5 3
4 9 18 49 160
(1.2) (2.7) (5.5) (15) (49)
17 35 70 188 614
(5.2)
(11) (21) (57) (187)
MAXIMUMEQUIVALENT EXHAUST PIPE
LENGTH-ONE CRITICAL MUFFLER INCLUDED
EQUIVALENT LENGTHS OF PIPE FITTINGS
TYPE OF FITTING
(INCHES)
STANDARD ELBOW
Feet (Metres)
LONG RAD. ELBOW
Feet (Metres)
MED. RAD. ELBOW
Feet (Metres)
STANDARD TEE
Feet (Metres)
1.5
I 2
(1.34) (1.62)
(0.85) (1.07)
(1.10) (1.40)
(2.83) (3.96)
9.3
2.5
6.4
(1.95)
4.2
(1.28)
5.4
(1.64)
14
(4.27)
3
8.1
(2.47)
5.2
(1.58)
6.8
(2.07)
17
(5.18)
SINGLE THIMBLE DIAMETER
DOUBLEVENTILATED THIMBLE
DIAMETER
6"( I52 mm) LARGER
THAN EXHAUST LINE
I~"~OS mm) LARGER OR
s IN END
SLEEVE
EXHAUST LINE PASSING THROUGH
II WALL OR PARTITION
FIGURE 4. EXHAUSTSHIELD
\ IF EXHAUST LINE MUST BE PITCHED
UPWARD CONSTRUCT A TRAP
OF PIPE
FITTINGS AT POINT OF RISE
DRAIN CONDENSATION TRAP
PERlODlCALLY
AG17
FIGURE 5. CONDENSATION TRAP
WARNING^
EXHAUST GAS IS DEADLY!
Exhaust gases contain carbon monoxide, a poisonous gas that might cause
unconsciousnessand death. Itis anodorlessandcolorlessgas formedduring
combustionof hydrocarbon fuels. Symptomsof carbonmonoxidepoisoning
are:
Dizziness Vomiting
Headache MuscularTwitching
Weaknessand Sleepiness Throbbingin Temples
If you experience any of these symptoms, get out into fresh air immediately,
shut down the unit and
do not use untilithas been inspected.
Thebest protection against carbonmonoxideinhalation is proper installation
andregular,frequentinspectionsof thecompleteexhaustsystem.
If younotice
a changein the sound or appearance of exhaust system, shut the unit down
immediately and have it inspected and repaired at once by a competent
mechanic.
15
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Cooling System
PURPOSE OF COOLINGSYSTEM
Purpose of the coolingsystem is to carry heat away
from hot engine components in order to maintain
properrunningconditions andclearances.Overheat-
ing can severely damage engines. The cooling sys-
tem must carry off the excess heat.
Regulatingcoolanttemperaturehelpskeeptheengine
attheoptimal heatlevelforeachoperatingcondition.
Afterstarting, theengine mustwarm upquickly. Dur-
ing periods of peak output, it must be adequately
cooled.
ANTI-FREEZEAND CORROSION
Corrosion can shorten anengine's lifebyplugging up
radiator cores, buildinguparound hotspots nearthe
exhaust valves, and settling inlowareasof the block.
The corrosive sediment insulates against proper heat
transfer and holds heat in. Mostof themetalsused in
coolingsystems aresusceptibletocorrosion damage
that causes coolant leaksandthetemperature to rise
above safe, normal limits.
To prevent corrosion, a mixture of anti-freeze and
water should always be used as an engine coolant,
even when freezing temperatures are not expected.
Besides preventing coolant freeze up, anti-freeze
contains rust inhibitors that prevent corrosion. Most
anti-f reeze manufacturers recommend a minimum
50-50 mixofethyleneglycolanti-freeze andwaterfor
winter and summer in closed water systems with a
complete change every year to avoid corrosion and
more expensive damage.
HIGHTEMPERATURE CUT-OFF SWITCH
The hightemperature cut-off switch shuts down the
engine if the coolant reaches a dangerously high
temperature. This normally closed switch senses
coolant temperature in the engine cooling jacket.
When engine temperature rises beyond a specific
pointtheswitchopens, breakingthecircuittothefuel
solenoid. When coolant temperature falls to a safe
operating rangetheswitch closes, permitting engine
restarting.
Stopping of the engine due to action of the high
temperature cut-off switch is nota normal condition.
Examinethe cooling system todetermine thecause
oftheoverheating and repair as required.
16
COOLING SYSTEM MAINTENANCE
The cooling system includingtheblock and radiator
should be cleaned and flushed at least once a year.
This
is especially true in cold weather conditionsor
when preparing unit for extended storage (over
30
days or more)!
The cooling system can work efficiently onlywhen it
is clean. Scale and rust in the cooling system slow
down heat absorption and restrict water flow.
Thethermostat iscalibratedtoopen at 150°F
* 2OF. It
should be checked also.
I
An appropriate anti-freeze mixtureshould beusedin
colder climates as necessary.
Check the fan belt tension periodically. For proper
operation of the water pump, thefan belt should be
tight enough to prevent slipping.
Check thewater pumpfor wear periodically. Loosen
thefan belt and movethefan and water pumppulley
back and forth. If wear is excessive, replace the
bearing.
Cleaning and FlushingCoolingSystem
To clean rust and scale deposits from the cooling
system, drain system and then fill with clean water
and cleaning solution. Use an approved chemical
cleaner (such as type used for cleaning automotive
coolingsystems)andfollow instructions providedby
thesupplier.
Contact with hot coolant might
resultinseriousburns.Donotbleed
hot, pressurized coolant from a closed cooling
system.
Cleaningsolutionstypicallycontain
strong chemicals that can cause
burns or other injury if used improperly. Read all
warning labels carefully before using.
When cleaning is complete, drain cleaning solution
and flush system. For best results engine and radia-
tor, or heat exchanger, should be reverse flushed.
Allow engine to cool as much as possible before
flushingwith coldwater.
Never pour cold wafer into a hot
engine. Doing
so may crack the
head or the cylinder block. Do not operate engine
without coolant for even a few minutes.
Flush system if engine operation indicates clogged
passagesoroverheating.
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Engine Water Jacket and Cylinder Head
External coolant leakage may occur at any of the
joints inthe engine water jacket such as the drain
plugs, core hole plugs, orcylinder head joint. Since
expansion or contraction can aggravate leakage,the
block should be inspected both hot and cold while
the engine is running.
Internalleakageoccurswhencoolant passesintothe
engine oil through a loose cylinder head joint or a
cracked or porous casting. The leakage isnotvisible
butmaycauseextensivedamagetotheengine. Cool-
ant mixes with the oil to form sludge which causes
lubricationfailure. Heavy sludge accumulations fol-
lowedbystickingpistonrings,valves,andtappetsare
symptoms of internal leakage.
Sometimes internalleaksaresmallenoughtoprevent
coolant leakagebutpermitexhaust gasestoenterthe
cooling system. The exhaust gases dissolve in the
coolant, depleting the rust inhibitors and forming
acid which causes corrosion.
Thermostat
Replacethermostat if it isbroken, corroded, orsticks
intheopen or closed position. Ifengine overheatsor
does not reach and maintain a minimum operating
temperature, the thermostat should be removed and
tested as a possible cause.
1. Removethermostat from cylinder head.
2. Heat a pan of water to approximately 150°F.
Check temperature using a thermometer im-
mersed inwater.
3. With thermostat suspended inwater at tempera-
ture of 150°F, thermostat should start to open.
4. After thermostat hasopened completely, remove
it from hotwater and allow ittocool insurround-
ing air. The thermostat should close within a
short time.
5. Ifthethermostat sticks ordoes notoperate prop-
erly, replace
it with'a new one.
6. Always install a new gasket when replacing the
thermostat.
Draining Cooling System
Whenever draining thecoolingsystem for changing
anti-freeze solution or for out-of-service protection
when only water is used, be sure to open all drains
andhoseconnectionswherewater couldbetrapped.
Contact with hot coolant might
resultinseriousburns.
Do notbleed
hot, pressurized coolant from
a closed cooling
system.
The following drain plugs must be removed to allow
completeflushing of the cooling system.
Radiator: One petcock lower right front corner.
Engine Block One drain plug left front near water
Pump.
Water Pumps: Onedrain plugundercoverorby loos-
ening cover.
If anoptionalwater jackettank heater is useditshould bedrained
andflushedalso.Thelowerhosemustbedisconnectedatthetank
heater.There is no drain plug.
After making repairs on the coolingsystem, tighten
all connections thoroughly. Use Permatex or thread
sealing compound on all threaded connections to
prevent leaksor the entry of air intothesystem.
Read instructionson PermatexSealercan beforeapplyingsealer
to engine parts.
Pressure Cap
The pressure cap increases the boiling point of the
coolant byallowing pressureto build upinthecool-
ingsystem. The increase inboiling pointreducesthe
chances for coolant loss due to boil over. A 15 psi
(103.5 kPa)pressurecapwill raisetheboilingpointof
water to 250°F (122°C) and the boiling point of a
50/50 mixture of water and anti-freeze to 265°F
(132°C). Pressurecaps should beinspected periodi-
callyfor freedom of operation andthe gasket should
bechecked for proper sealing. Replacethepressure
cap if it malfunctions.
17
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RADIATOR COOLED SYSTEM
On radiator cooled models (Figure 6), the water
pump draws cooled water from the radiator through
thebottomhoseandforces itintothecylinder water
jacket atthefront of theengine.Thewater circulates
through the cylinder water jacket up through the
cylinder heads to the thermostat and flows through
the outlet hose intothe top of the radiator.
It circu-
lates downthroughthe radiator while the fan blows
cooling air across the radiator. The water is drawn
from the bottom of the radiator by the pumpto be
recirculated.
Water Pump
A centrifugal typewater pump (Figure 6a) circulates
coolant through coolingsystem. The water pumpis
secured tocylinder block with capscrews and isbelt
driven from the crankshaft pulley. Coolant isdrawn
through pump inlet opening by the impeller and
forced through outlet opening in backside of pump
into cylinder block.
A gasket on water pump outlet
assures a leakproof connection.
PUMP
BY-PASS LINE
I
WATER PUM,P
HOUSING GASKET
FIGURE 6a. WATER PUMP-EXPLODED VIEW
LEGEND
- - WATER FLOW, ENGINE COOLING
-AIR FLOW. ENGINE VENTllATlON
FIGURE 6. RADIATOR COOLING SYSTEM
During engine,warmup, when the thermostat is
closed, the water bypasses the radiator.
It flows
through a bypass linefrom the water outlet housing
to the pump and recirculates through the engine.
When water in the e.ngine block reaches normal
operating temperature, the thermostat opens. This
permits heated water to flow into the radiator to be
cooled.
Recirculation ensures both rapid and even tempera-
ture increase of allengine parts during warmup.
Ventilation for radiator cooled models requires an
inlet opening for fresh air and an outlet opening for
hated air to prevent recirculation
of heated air. The
openings should be at least the size of the radiator.
An expansion area in fhe closed
cooling system maintains proper
coolantlevel
by prevenfingoverflowandloss of cool-
ant when engine heats up.
The water pump is constructed to provide long life
with a minimum amount of attention when proper
corrosion preventive coolant is used. Care must be
taken to keep grit and abrasive material from being
circulatedthroughcooling system.Water containing
scale-forming materialsisespecially harmfultopump
parts.
Thepumpcannot berebuilt andmust bereplacedas
a unit. Check condition of bearing and shaft assem-
bly by turning water pump pulley. If bearing feels
roughorbinds,seal isleaking, orhousing iscracked,
the pump must be replaced.
Removal and Installation
1.
2.
3.
4.
5.
6.
7.
8.
9.
Drain cooling system at radiator and engine
block.
Removehousing from radiator as necessary.
Disconnect both hosesfrom radiator.
Removeradiator.
Loosenfan belt.
Removefan and water pump pulley.
Disconnect by-pass lineand radiator lower hose
from pump.
Removewater pump from water pump housing.
Installation is the reverse
of removal.
18
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