Cleaning, Inspection, and Repair - TM-55-4920-226-150121

seal retainer, insert the retainer in the port

208. Cleaning, Inspection, and Repair

block (52) and secure with the six screws (43).

a. Clean all metal parts with an approved

e. install plugs (33) in the pump body (34).

cleaning solvent and dry with a lint free cloth.

Install the dowel pin (32) in the port block

b. Rotate the bearings and inspect for rough

(52). Place a new O-ring gasket (36) and the

rolling elements and races. Replace a defective

pump body on the port block and secure with

or worn bearing.

the six screws (35).

c. Inspect the creep plate for pits, scores and

f. Apply a film of hydraulic oil to the port

scratches. Replace a defective creep plate.

plate (31). Install the port plate in the pump

d. Inspect the piston and shoe assembly, and

body (34) over the splined end of the shaft

the cylinder barrel for pits, scratches, and abra-

and sleeve assembly. Turn the port plate in the

sion. If either item is found to be defective the

direction of pump rotation until the last of the

barrel and bearing assembly must be replaced

three holes in the back of the port plate engages

as a matched set.

the dowel pin (32). Make certain the port plate

e. Inspect the port plate for scratches and dis-

will move slightly and freely.

tortion. Remove scratches by lapping. Replace

g. Position the inner race of bearing (29)

a port plate damaged beyond repair.

on the cylinder barrel (27) and secure with the

f. Inspect the shaft seal lip for cracks and

seven screws (28). Apply a film of hydraulic

scratches. Replace a damaged seal or one that

oil to the barrel and bearing and slide the barrel

has been leaking.

into the pump body.

g. Inspect the splines of the shaft and sleeve

h. Install the spring retainer pin (25), spring

assembly for cracked or chipped teeth. Replace

retainer (24), spring (23), spring socket (22),

a damaged shaft and sleeve assembly.

and ball (21) in the cylinder barrel.

h. Inspect the index plate for nicks, burs,

i. Install the retainer, piston and shoe as-

scratches and abrasion. Replace a defective in-

sembly (18) in the cylinder barrel (27). Make

dex plate.

certain the pistons enter the same bore from

which they were removed.

i. Inspect the port block for cracks, breaks,

j. Place a new O-ring gasket (30) on the pilot

and damaged threads. Check the face which

of the pump- body and install the outer race of

mates with the port plate for irregular sur-

the bearing (29) on the inner race.

face. Reface by crown grinding, the center be-

ing 0.0002 to 0.0004 inch high. Replace a port

k. Install the two plugs (24 and 25, fig, 39)

block damaged beyond repair.

in the hanger housing (26).

l. Press the two needle bearings. (22) into the

j. Inspect all other parts for cracks, breaks,

hanger (23).

distortion, and damaged threads and replace if

m. Install the indicator operating pin (20),

defective.

two setscrews (19 and 21), and the bolt (18) in

209. Reassembly and Installation

the hanger.

a. Place 2 new O-ring gaskets (41, fig. 37) on

n. Install the two dowel pins (17) and the

the port block (52). Position the suction and

index plate (15) on the hanger (23) and se-

pressure flanges (37 and 39) on the port block

cure with the screw (16). Make certain the in-

and secure with the 8 screws (38 and 40).

dex plate is installed in accordance with marks

made during disassembly.

b. Press the 2 ball bearings (49) and 2

spacers (50) onto the shaft and sleeve assem-

o. Install the two trunnion spacers (14) in

bly (51) and secure with the washer (48) and

the hanger housing (26).

locknut (47).

p. Install two new O-ring packings (13) on

c. Install the shaft and sleeve assembly in the

the two trunnion pins (12). Position the hanger

port block.

(23) with attached parts in the hanger hous-

ing and insert the two trunnion pins in the

d. Install the seal (44) in the seal retainer

alined holes of the spacers and needle bearings.

(42). Place a new O-ring packing (45) on the

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AGO 5742A