TM-9-2520-234-35

POWER TRAIN ASSEMBLY; ALLISON MODEL XTG411-2A

TECHNICAL MANUAL; FIELD AND DEPOT MAINTENANCE MANUAL

JULY 1962

TM-9-2520-234-35 - Page 106 of 323

CHAP 5, SEC I

PRELIMINARY INSTRUCTIONS FOR

PAR 72

POWER TRAIN OVERHAUL

tightness of fit in the bore. If defects are

found, replace the bearing using the proper

replacer.

Note . Do not remove needle bear-

ings unless replacement is neces-

sary, since removal usually results

in destruction of the bearing.

d . Bushings, Bushing-type Bearings

-

and Thrust Washers

(1) Inspect bushings and bushing-

type bearings for size, scoring and out-of-

roundness, burrs, sharp edges and evidence

of seizing. Minor scores, sharp edges and

scratches may be removed with crocus

cloth.

Out-of-round, deeply scored or

worn parts should be discarded.

Note.

Do not remove bushings

bushing-type bearings unles s

replacement is necessary, as re-

moval usually damages thes e

parts.

(2) Remove bushings and bushing-

type bearings by using a puller or press

when possible.

Bushings in blind holes

may require removal by sawing or the use

of a narrow cape chisel.

Caution . If necessary to cut out a

bushing, do not damage the bore

into which it fits.

(3) Inspect thrust washers fo r

wear, distortion, scores and burrs.

Cor -

rect minor defects but replace parts that

are worn, scored or deformed.

e . Oil Seals, Preformed Packings

and Gaskets

(1) Inspect hook-type seal rings

for wear, distortion and broken hooks.

Replace defective seal rings. Install a

new hook-type seal ring if the ring shows

any wear on the outside circumference, or

if there is excessive side wear. The sides

of the seal ring must be smooth within

0.005-inch maximum side wear. The sides

of the shaft groove (or the bore) into

which the seal ring fits should be smooth

within 50 microinches equivalent an d

square with the axis of rotation within

0.002-inch. If the sides of the grooves

have to be reworked, install a new seal

ring.

(2) Inspect

metal-encased lip -

type seals for cracks, wear, cuts and brit-

tleness. Inspect springs and seal shells.

Replace any seals found defective.

Note . Any time a metal-encased

lip-type seal is removed, it must

be replaced with a new seal.

f . Gear s

(1) Inspect gears for burrs, wear,

pitting and broken teeth at tooth contact

areas.

(2) Inspect bores of planetar y

pinions for wear and pitting of bearing

contact areas.

(3) Remove burrs using a sof t

honing stone. Replace gears that ar e

excessively worn or pitted.

g . Splined Parts

(1) Inspect

splined part s

for

twisted or broken splines, burrs and ex-

cessive wear.

(2) Remove burrs using a sof t

honing stone. Replace parts which have

twisted or broken splines and excessive

wear.

h . Clutc h Plate s

(1) Inspect friction-faced stee l

plates for burrs, embedded metal par-

ticles, severely pitted faces, excessive

wear, cracks, distortion and damage d

splined teeth. Remove burrs using a soft

honing stone. Replace plates which have

other defects.

(2) Inspect steel plates for burrs,

scoring, excessive wear, distortion, em-

bedded metal, galling, cracks, breaks and

damaged spline teeth. Remove burrs and

minor surface irregularities using a soft

honing stone. Replace plates which have

other defects.

76 Change 2