CH-34 Tail Rotor Counterweight Assembly Balance Check

TM 55-4920-201-14

are positioned counter clockwise from their

4-60. CH-34 Tail Rotor Counterweight Assembly

respective clevis blocks.

Balance Check. (See figure 4-36).

h. Insert ball ends of turnbuckles in slots of

a. Center adapter plate assembly (1), with

clevis blocks, and install four bolts, part no. AN4-

plate hub projection upward, on stand table

13A, through clevis locks, with bolt heads toward

assembly (1, figure 1-13).

outside edge of adapter plate assembly (1). Align

b. Place spacer (2) on top of adapter plate

turnbuckles approximately parallel with balancing

assembly (1) hub with inside chamfer of spacer

arbor (6).

upward.

c. Center flat face of tail rotor counterweight

NOTE

assembly (3) hub on spacer (2).

Installation of nuts on bolts, part no. AN4-

d. Install bushing (4), with pilot end

13A, is not essential, but check frequently

downward, on balancing arbor (6) so that top

to make certain that bolts do not shift

surface of bushing aligns with 12-inch position on

position in clevis blocks during balance

arbor scale (7). Secure bushing in this position by

checking operations.

tightening bushing setscrew (5) with 1/8-inch hex

wrench (8, figure 1-13).

i. Install 3 / 16-inch suspension cable (13,

figure 1-13) and quick-disconnect coupling (10)

e. Insert lower end of balancing arbor (6,

assembly on suspension rod at top of arbor, and

figure 4-36) downward through tail rotor coun-

engage suspension cable in lifting plate of hydraulic

terweight assembly (3) hub, spacer (2), and

pump assembly.

adapter plate assembly (1) hub, pushing arbor all

the way down until tapered pilot on bushing (4)

j. Hoist entire assembly approximately

seats firmly into counterbore of counterweight

inch off work stand. Check to insure that

assembly hub.

suspended assembly is free from interference with

work stand and other objects, and note balance

f. Install spacers (9) on lower end of

condition indicated by black indicator disc at top

balancing arbor (6). Install hand wheel (26, figure

end of the arbor.

1-13) in bottom end of arbor, and tighten to clamp

assembly firmly together.

k. For balance tolerance and application of

balance corrections, refer to applicable helicopter

g. Rotate counterweight assembly so that

manual. (Refer to appendix A).

turnbuckles align vertically with adapter plate

clevis blocks (8, figure 4-36) and counterweights

4-57