Reassembly of Mast Assembly

TM 10-3930-609-35

capscrews and lockwashers to retain latch pins. Hook

3-81. Repair and Replacement of Mast Parts

latch springs to latches.

a. Reweld parts where welds have broken only if

parts are not distorted. Use gas or electric arc welding

I. Install latch operating capscrews in outer and

equipment. Repaint welded surfaces.

intermediate channels.

b. Replace all broken or distorted or worn parts

m. Install bearings in chain rollers; then, aline chain

with serviceable parts.

roller in crosshead and insert roller shafts. Secure roller

shafts in crosshead with lockscrews.

3-82. Reassembly of Mast Assembly (fig. 3-14)

n. Install latch operating capscrews in crosshead.

a. Install lubrication fittings in outer channel, in

o. Aline crosshead with guides in intermediate

roller pins, in latch pins, in crosshead roller shafts and in

channel and install guides on crosshead with capscrews

trunnions of carriage weldment.

and lockwashers, including quantity of shims between

b. Attach inserts to outer, intermediate and inner

guides and crosshead that will center crosshead. Use

sufficient shims to eliminate side play -of crosshead

channels.

without binding in guides.

c. Install chain anchors in bracket of outer channel,

p. Install hoist cylinder as described in paragraph

using nuts and lockwashers.

2-15.

d. Slide intermediate channel into outer channel.

q. Install setscrews in channels.

e. Install bearings in rollers; then, place rollers into

r. With channels horizontal, tighten setscrews in

position in inner channel and insert roller pins. Secure

carriage side plates to tension side thrust rollers lightly

roller pins in position with lockscrews.

but not tightly against inner channel. Tighten short

f. Install bearings in carriage rollers and place

setscrews against long setscrews to lock the adjustment.

washers and rollers on carriage weldment trunnions.

s. With channels vertical, install setscrews in

g. Secure brackets to carriage weldment with bolts

inner, intermediate and outer channels to eliminate play

and washers; then, install setscrews in carriage

between channels and inserts. Do not tighten to point of

weldment side plate but do not tighten setscrews against

causing binding of channels.

brackets.

t. Apply grease GAA to lubrication fittings in roller

h. Install striker bar on carriage weldment side

pins, in latch pins, in crosshead roller shafts and in

plate with capscrews and lockwashers.

carriage trunnions (LO 10-3930-609-2).

i. Install side thrust rollers in brackets in carriage

v. Apply grease GAA to points of contact between

weldment.

all three channels (LO 10-3930-609-12).

j. Insert rollers on carriage weldment in inner

w. Install chain (TM 10-3930-609-12).

channel; then, engage inner channel in intermediate

channel.

k. Install latch pins and latches on inner channel

and intermediate channel, using bars secured with

Section XII. OVERHAUL AND REPAIR OF TRAVEL MOTOR

Removal of the travel motor is required for overhaul as

3-83. Description of Travel Motor

described in the following instructions. To remove travel

The travel motor is a four-pole, series connected,

motor, refer to paragraph 2-24.

reversible, spark enclosed dc motor capable of

approximately 3.5 horsepower output when energized at

36 volts. The armature shaft is splined on one end for

3-85. Disassembly of Travel Motor (fig. 3-15)

mounting the pinion used to drive the power axle. The

a. Remove screw, nut and lockwasher which

opposite end of the armature shaft is designed for

secure two yoke covers around motor front yoke; then,

mounting the parking brake drum. The armature shaft is

disengage yoke covers from shouldered pins in yoke

ball-bearing mounted at both ends. Bearings are grease

and remove yoke covers. Do not remove shouldered

packed and require no additional lubrication.

pins from yoke unless replacement is required.

b. Disengage eight brush springs from brush-

3-84. Removal of Travel Motor

holders and remove springs from motor front yoke.

3-26