TM 9-1240-400-34&P
5-19. FINAL INSPECTION INSTRUCTIONS (CONT).
CHECKING AND ADJUSTING ELEVATION KNOB TORQUE AND BACKLASH (CONT)
(10) that secure telescope mount subassembly (11) to
housing (8). Remove telescope mount subassembly
(11). Do not remove two pins (12) unless damaged.
7 Place gunner's quadrant (1) on level bar (2) and rotate
bevel gear (13) until minimum travel (elevation 1333
mils and depression 89 mils (9911)), as read on
elevation counter (4), can be met. Ensure that slight
overtravel (one or two gear teeth) is obtained.
8 With telescope mount subassembly rotated clockwise
to a stop, install telescope mount subassembly (11)
and secure with three lock- washers (10) and three
capscrews (9).
9 Check that elevation counter (4) readings at elevation
of 1333 mils and depression of minus 89 mils are
within 1.0 mils of the angle indicated by gunner's
quadrant (1).
10 Level M137 telescope mount using elevation and
cross-level vials (14). Check that elevation counter
(4) indicates "0000".
11 If required, loosen four screws (15), pull elevation
counter (4) back and rotate gear (16) to set elevation
counter to "0000". Tighten four screws (15).
12 Recheck elevation knob (3) travel. Adjust travel as
required by repeating steps 5 thru 9.
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