TM 5-3820-233-35/1
(3) Inspect shafts for scoring and wear.
Replace a defective shaft.
(4) Inspect all bushings for distortion or
wear. Replace defective or worn bushings.
(5) Inspect gear pockets finished sur-
faces for scratches, scoring, or wear. Replace
the pump body and cover if wear is indicated.
(6) Inspect the pressure relief valve and
its seat in the pump body for wear or other
damage. Replace defective parts as necessary.
(7) Check relief valve spring compres-
sion. A force of 48-53 pounds is required to
compress the spring to a length of 1.596
inch. Replace the spring if a load of less than
48 pounds will compress the spring to 1.596
inch.
(8) Inspect regulator valve for freedom
of movement in the regulator body. Replace
a defective regulator valve.
(9) Check pressure regulator spring
compression. A force of 14-15 pounds is re-
quired to compress the spring to a length of
44. Lubricating Oil Pump and Pressure
1.656 inch. Replace the spring if a load of
Regulator Assembly
less than 14 pounds will compress the spring
to 1.656 inch.
pump is mounted on the first and second
e. Reassembly. Reassemble the lubricating
main bearing caps, and is gear driven from
oil pump and pressure regulator assembly in
the front end of crankshaft. An integral
the reverse of the numerical sequence as
plunger type relief valve bypasses the oil to
illustrated on figure 21-2.
the inlet side of the pump when the pressure
f. Installation
in the lubrication system exceeds 105 psi.
(1) Refer to figure 21-1 and install the
b. Removal
lubricating oil pump and pressure regulator
assembly.
(1) Drain the engine oil (Operator's
Manual).
Note. If new gears were installed on the oil
(2) Remove the power unit (para 24).
pump, it will he nessary to reshim the pump to ob-
(3) Remove the engine oil pan (para
tain proper backlash between the crankshaft gear and
oil pump idler gear. Correct backlash is 0.002 inch to
43).
0.012 inch. The insertion of one 0.005 inch shim
(4) Remove the engine lubricating oil
under each side increases the backlash 0.0035 inch.
pump and pressure regulator assembly from
(2) Install the oil pan (para 43).
the bearing caps as illustrated on figure 21-l.
(3) Install the power unit (para 24).
c. Disassembly. Disassemble the oil pump
(4) Refill with engine (Operator's Man-
and pressure regulator assembly in the nu-
ual).
merical sequence a s i l l u s t r a t e d o n f i g u r e
21-2.
45. Piston and Connecting Rod Assemblies
d. Cleaning, Inspection, and Repair
(1) Clean all parts with an approved
a. General. The piston and connecting rod
cleaning solvent and dry thoroughly.
assemblies consist of the pistons, pins, bush-
(2) Inspect the pump gears for cracked,
ings, piston rings, connecting rods, and
scored, worn, or clipped teeth. Replace a
defective gear.
four above the piston pin and two below.
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