TRUCK SERVICE MANUAL
ENGINE
Electric Connections
Secure electric connections to mounted equipment,
using wire as specified. See engine wiring diagram.
Fan Installation
Note: When installing fan to fan hub 5/16 inch [7.94 mm]
capscrew must have 15/32 inch [11.91 mm] thread
engagement, 3/8 inch [9.53 mm] capscrews must have
9/16 inch [14.29 mm] thread engagement, 1/2 inch
[12.70 mm] capscrews must have 3/4 inch [19.05 mm]
thread engagement. Check decal on fan hub or water
pump pulley for proper thread length. The fan may be
installed before or after engine dynamometer testing.
ENGINE TESTING
1-2. Priming Points
Engine break-in and testing are accomplished
Fig. 1433, (N11963). Lubricating system priming point
simultaneously. Break-in on a new or rebuilt engine is
CAUTION
necessary because it provides an operating period
Do not prime engine lubricating system from bypass
during which moving parts acquire their final finish and
filter.
mating surfaces reach a full seat. Engine testing helps
detect possible assembly errors, need for adjustments
3. Connect a hand or motor driven priming pump
as engine "break-in " and establishes a period for final
line from source of clean lubricating oil to plug boss in
adjustments for best engine performance.
housing. Prime until a 30 psi [2.1 kg/sq. cm] maximum
pressure is obtained.
Priming The Fuel System
4. Crank engine at least 15 seconds (with fuel
1. Fill fuel tanks and filter(s) with clean No. 2 diesel
shutoff valve closed or disconnect to prevent starting),
fuel oil meeting the specifications in Group 18.
while maintaining external oil pressure at a minimum of
a. With PT (type G) fuel pump, fill pump through
15 psi [1.1 kg/sq. cm].
plug next to tachometer with clean fuel.
5. Remove external oil supply line and replace
plug.
2. If injector and valve or other adjustments have
WARNING
been disturbed, be sure they have been properly
Clean area of any lubricating oil spilled while priming
adjusted before starting engine.
or filling crankcase.
Priming The Lubricating System
6. Finish filling crankcase to "H" (high) mark on
Note: If engine is equipped with a turbocharger, remove
dipstick.
oil inlet line and lubricate bearing with approximately 2 to
3 oz [60 cc] of clean engine lubricating oil. Reconnect oil
Lubricating Cranking Motor And Generator
inlet line.
Use 6 or 8 drops of clean lubricating oil to lubricate
cranking motor and generator or alternator bearings (if
1. Fill crankcase to "L" (low) mark on dipstick. See
required), Avoid excessive oiling which would cause
Lubricating Oil Specifications, Group 18.
damage to wire insulation.
equipped with hydraulic governed fuel pumps. This
Note: Some engine dipsticks have dual markings with
governor uses lubricating oil (of the same weight as used
high and low level marks; static oil marks on one side
in the engine) as an energy medium. Oil level in
and engine running at low idle speed marks on opposite
governor sump must be at full mark on dipstick, or
side. Be sure to use proper scale.
halfway level on inspection glass.
2. Remove plug from head of lubricating oil filter
Engine Dynamometer
housing or gear case to prime system. (See 1 or 2, Fig.
Check dynamometer capacity, Make sure capacity is
1433.)
sufficient to allow testing at 96 to 100% maximum engine
If capacity is insufficient, testing
procedures must be modified to prevent damage to
dynamometer
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