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 134 of 590

TM

9-1240-401-34&P

4-14. DISK ASSEMBLY MAINTENANCE INSTRUCTIONS - continued

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c. Assembly - continued

14 Install cover (5) between bosses and slide level (3)

into disk assembly (4).

15 Using fabricated eccentric tool, install cell (2) and

threaded ring (1). Do not tighten pending final ad-

justment.

2

3

4

5

6

7

8

9

1

Install perpendicularity gage (33) on M145/M145A1

telescope mount (34) or use two parallel bars

across body of mount if perpendicularity gage is

not available.

Level the cross-leveling fixture in elevation and

cross-level.

Set the zeroed M1A1 gunner’s quadrant (35) on

the perpendicularity gage (33).

Adjust pitch knob (36) until M1A1 gunner’s quad-

rant level (37) bubble is centered.

Adjust elevation handwheel (36) until elevation

counter (39) reads zero.

Engage fabricated eccentric tool to the threaded

ring (1).

Insert a common straight blade screwdriver

through the center hole in fabricated eccentric tool

and engage cell (2).

Adjust cell (2) until the level (3) bubble is centered

within the graduations on level (3).

Hold cell (2) firmly in place while turning fabricated

eccentric tool to tighten threaded ring (1). Be care-

ful not to disturb the setting of level (3).

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d. Adjustment

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