Section III. MAST GROUP

(1) Place armature in a lathe and turn down

(3) commutator lightly with No. 00 sandpaper

commutator until true. Make certain cut is not made on

to remove an)y burrs left from undercutting.

commutator riser bars as solder will be removed,

(4) Check armature on a growler for short

weakening coil connections at this section. Remain

circuits. Refer to subparagraph h.

j. Reassembly. Reassemble pump motor in the

approximately 3 / 16 inch from riser bars when cutting.

(2) Undercut mica between bars to a depth

reverse order of disassembly.

Note.

not exceeding 0.030inch. Undercut must be full width of

Prior to reassembly, lubricate

mica and flat at bottom. After undercutting, clean out

bearings in accordance with LO 10-3930-620-12.

slots to remove any dirt and copper dust.

Section III. MAST GROUP

a. Removal.

Mast repair can usually be

3-26. General

The mast group of the vehicle consists of a mast

accomplished without removal from the truck.

assembly, carriage and backrest assembly, and forks.

necessary, remove the mast assembly according to

The hydraulic lift mast consists of an inner mast, an

b. Disassembly. (fig. 3-39.)

intermediate mast, and an outer mast. The intermediate

and inner masts ride on adjustable roller bearings,

(1) Remove the chains (8 and 20), bolts (10

enabling them to telescope up and down smoothly and

and 22), hydraulic line and support (25). Remove the

with a minimum of drag. The carriage assembly is a

elbows, fitting and flow regulator from the primary and

welded structure having horizontal upper and lower fork

secondary lift cylinders.

support bars and a pair of vertical carriage support bars.

3-27. Mast Assembly

3-57