TM 5-3820-233-35/2
(4) Remove the engine lubricating oil pump
and pressure regulator assembly from the bearing caps
as illustrated on figure 24-1.
c. Disassembly. Disassemble the oil pump and
pressure regulator assembly in the numerical sequence
as illustrated on figure 24-2.
d. Cleaning, Inspection, and Repair
(1) Clean all parts with an approved cleaning
solvent and dry thoroughly.
(2) Inspect the pump gears for cracked,
scored, worn, or clipped teeth. Replace a defective
gear.
(3) Inspect shafts for scoring and wear.
Replace a defective shaft.
(4) Inspect all bushings for distortion or wear.
Replace defective or worn bushings.
Figure 22-1. Cylinder head, removal and installation
(5) Inspect gear pockets finished surfaces for
scratches, scoring, or wear. Replace the pump body
d. Cleaning, Inspection, and Repair
and cover if wear is indicated.
(1) Clean all parts with an approved cleaning
(6) Inspect the pressure relief valve and its
solvent and dry thoroughly.
seat in the pump body for wear or other damage.
(2) Inspect the oil pan for dents and
Replace defective parts as necessary.
punctures. Replace an excessively damaged oil pan.
(7) Check relief valve spring compression. A
(3) Replace the oil pan gasket.
force of 48-53 pounds is required to compress the spring
(4) Inspect the mounting bolts and drain plugs
to a length of 1.596 inch. Replace the spring if a load of
for damaged threads. Replace damaged parts as
less than 48 pounds will compress the spring to 1.596
necessary.
inch.
(8) Inspect regulator valve for freedom of
the oil pan assembly.
movement in the regulator body. Replace a defective
regulator valve.
f. Installation.
(9) Check
pressure
regulator
spring
(1) Secure the oil pan gasket and oil pan to
compression. A force of 14-15 pounds is required to
the engine block.
compress the spring to a length of 1.656 inch. Replace
(2) Install the power unit (para 23).
the spring if a load of less than 14 pounds will compress
(3) Refill with engine oil (Operator's
the spring to 1.656 inch.
Manual1).
e. Reassembly. Reassemble the lubricating oil
pump and pressure regulator assembly in the reverse of
45.
Lubricating Oil Pu mp and Pressure
the numerical sequence as illustrated on figure 24-2.
Regulator Assembly
f. installation
a. General. The gear type lubricating oil pump is
(1) Refer to figure 24-1 and install the
mounted on the first and second main bearing caps, and
lubricating oil pump and pressure regulator assembly.
is gear driven from the front end of crankshaft. An
integral plunger type relief valve bypasses the oil to the
inlet side of the pump when the pressure in the
lubrication system exceeds 105 psi.
the oil pump, it will be necessary to
reshim the pump to obtain proper
b. Removal
backlash between the crankshaft
(1) Drain the engine oil (Operator's Manual).
gear and oil pump idler gear. Correct
(2) Remove the power unit (para 23).
backlash is 0.002 inch to 0.012 inch.
(3) Remove the engine oil pan (para 44).
The insertion of one 0.005 inch shim
under each side increase the
backlash 0.0085 inch.
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