OH-23 (Series D, F, and, G) Tail Rotor Hub and Yoke Assembly Balance Check.

TM 55-4920-201-14

4-47. OH-23 (Series D, F, and, G) Tail Rotor Hub

position on arbor scale (6) aligns with top surface of

and Yoke Assembly Balance Check. (See figure 4-

rotor splined hub. Lock arbor in this position by

moderate and uniform tightening of two lower

fixture setscrews (7), using 3 / 32-inch hex wrench

a. Set fixture assembly (2), recessed side up, on

suitable auxiliary support block (1).

e. Install quick-disconnect coupling

b. Place spacer (3) central on top of fixture

(7HEL053 or 7A050 kit) on arbor suspension

assembly 12) hub.

coupler, and suspend entire assembly free of in-

c. Set tail rotor hub and yoke assembly (4)

terference, and note the balance condition indicated

central on spacer (3), with hub shafts resting on rim

by black indicator disc at top end of the arbor.

of fixture assembly (2).

f. For balance tolerance and application of

d. Insert lower end of balancing arbor (5)

downward through rotor hub splines, spacer (3),

balance corrections refer to applicable helicopter

manual. (Refer to appendix A).

and fixture assembly (2) hub until 7 5/8-inch

4-46