12 Drive gear
16 Oil cooler bypass valve
7 Pump body
20 Oil pressure regulator valve
9 Cover plate
21 Oil seal
10 Inner rotor
11 Outer rotor
Figure 3-3. Oil pump, disassembly and reassembly.
(2) Inspect all mounting hardware for
3-3. Oil Cooler
a. General. The oil cooler is attached directly to
(3) Inspect core for damage. Clean oil passage
t h e cylinder block. Cooling water circulated
with compressed air. Replace damage or defective
through the oil cooler completely surrounds the oil
cooler core. Therefore, whenever an oil cooler is
e. R e a s s e m b l y . R e f e r t o f i g u r e 3 - 5 a n d
assembled, special care must be taken to have the
reassemble oil cooler.
proper gaskets in place and the retaining bolts tight
f. Pressure Test.
to assure good sealing.
(1) Make a suitable plate and attach to flange
side of cooler core. Use a gasket made from rubber
(1) Drain cooling system by opening drain
to assure tight seal. Drill and tap the plate to permit
cock at bottom of oil cooler housing.
an air hose fitting to be. attached to inlet side of
(2) Remove any accessories or other equip-
m e n t necessary to provide access to the oil cooler.
(2) Apply approximately 75 psi air pressure
(31 Refer to figure 3-4 and remove the oil
and submerge cooler core and plate assembly in
container of water. Any leaks will be indicated by
c. Disassembly. Refer to figure 3-5 and
air bubbles in. the water. If leaks are indicated,
disassemble oil cooler.
replace the core.
(1) Inspect housing for cracks, breaks and
(1) Refer to figure 3-4 and install oil cooler.