CHAPTER 3 REPAIR OF ENGINE - TM-10-3930-242-340041

TM 10-393-242-34

CHAPTER 3

REPAIR OF ENGINE

Section I. ENGINE ACCESSORIES

(2) Refer to figure 3-1 and remove oil pump

3 - 1 . General

and crankshaft pulley.

This section contains information on the

c . Disassemble. Refer to figure 3-2 and disas-

maintenance of those items considered to be en-

s e m b l e oil pump in numerical sequence.

g i n e accessories. They consist of the oil pump,

d. Cleaning and Inspection.

o i l cooler, air inlet housing, blower assembly,

(1) Clean the pump thoroughly with dry

speed limiting governor, radiator, generator,

c l e a n i n g solvent such as P-D-680, or equal, to

and starter.

remove all traces of dirt, sand, or foreign matter

t h a t might damage the pump.

3-2. Oil Pump and Crank Shaft Pulley

( 2 ) The greatest amount of wear in the oil

a. General. The rotor-type oil pump is bolted

pump occurs on the lobes of the inner rotor (10,

t o back of engine lower front cover and driven

f i g u r e 3-2) and outer rotor (11) of each lobe.

d i r e c t l y by the crankshaft. Oil is directed to

Clearance should not be less than 0.004 inch nor

lower engine front cover and then to a main oil

more than 0.011 inch.

gallery in cylinder block under pressure to main

( 3 ) Using a micrometer depth gage, meas-

b e a r i n g s , balance shaft, and camshaft bearings.

ure the distance from the face of the pump cover

The crankshaft pulley is used to drive the

(12) to sides of inner rotor (10) and outer rotor

generator and fan.

(11). Clearance should not be less than 0.001 inch

b . Removal.

nor more than 0.0035 inch,

(4) Discard the gasket (7) and seal (14).

(1) Remove the engine (para 2-5).

( 5 ) Replace all defective parts.

e. Reassembly.

NOTE

Rotors are obtainable only in matched sets.

( 1 ) Refer to figure 3-2 and reassemble the

oil pump with the exception of the seal (14).

( 2 ) Install the seal with the cup side facing

inward.

3-3. Oil Cooler

a. General. The oil cooler is attached to an oil

c o o l e r adapter attached to the cylinder block.

The flow of oil is from oil pump through a pas-

sage in the oil cooler adapter to full flow oil filter

a n d then through the oil cooler core and cylin-

der block oil galleries,

b. Removal.

(1) Drain cooling system by opening drain

cock at bottom of cooler housing.

( 2 ) Remove fuel filter, oil filter, and water

pump (TM 10-3930-242-12).

( 3 ) Refer to figure 3-3 and remove the oil

cooler.

c . Disassembly. Refer to figure 3-4 and disas-

Figure 3-1. Oil pump and crankshaft pulley, removal and

semble oil cooler.

installation.

3-1