TM-9-1240-401-34-P

TELESCOPE MOUNT M146: M118A2 AND M118A3; TELESCOPE MOUNT M145: M145A1; PANORAMIC TELESCOPE: M117 AND M117A2; FIRE CONTROL QUADRANT: M15; PERISCOPE: M42

TECHNICAL MANUAL; DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL

JULY 1993

TM-9-1240-401-34-P - Page 142 of 590

TM 9-1240-401-34&P

4-16. QUADRANT SUPPORT ASSEMBLY MAINTENANCE INSTRUCTIONS - continued

I

I Assembly - continued

I

11 Install

plate (7), two lug terminals (6), and two ma-

chine screws (5).

12 Install plate insulator (4), plate insulator (3), two

new lockwashers (2), and two machine screws(1).

13 Install V-bearing (10), spring (9), and retainer (8)

on M145A1 telescope mount.

d. Adjustment

I

2

3

4

5

6

7

8

9

10

1

Clamp a 3/8-x 3/4-x 6-inch parallel bar to quad-

rant seat of bracket parallel to the quadrant supporl

assembly level (29).

Position a zeroed M1A1 gunner's quadrant (35) on

parallel bar, parallel to level (29).

Adjust quadrant support assembly level knob (34)

until M1A1 gunner’s quadrant (35) level (36) bub-

ble is centered.

Loosen threaded ring (26) using fabricated eccen-

tric tool.

Apply sealing compound to threaded ring (26) and

install threaded ring (26) in bracket.

Engage fabricated eccentric tool into holder (27)

and threaded ring (26).

Insert a common straight blade screwdriver

through the center hole in the fabricated eccentric

tool and engage control cam (28).

Adjust control cam (28) and holder (27) until the

level (29) bubble is centered within the graduations

on the level (29).

Rotate level assembly from 0 to 1330 mils and ad-

just control cam (28) and holder (27) until the level

(29) bubble is centered within the graduations on

the level (29).

Rotate level assembly from 1330 roils to 0 and ad-

just control cam (28) and holder (27) until the level

(29) bubble is centered within the graduations on

the level (29).

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