TM 9-1240-400-34&P
5-19.
FINAL INSPECTION INSTRUCTIONS (CONT).
CHECKING AND ADJUSTING CROSS-LEVEL KNOB TORQUE AND BACKLASH
1
Using torque wrench and torque adapter (8213490), measure the torque required to turn cross-level knob (1). The
torque shall be 5.00 to 11.00 in.-lb (0.56 to 1.24 N-m). If not, adjust according to adjustment procedure. Refer to step
8.
2
Rotate cross-level knob (1) in one direction to center bubble of cross-level vial (2).
3
Scribe a line on boss (3) and knob (1).
4
Place gunner's quadrant (4), with end-for-end correction applied, on top mounting surface of M137 telescope mount
(5), parallel to two locating pins (6). Rotate gunner's quadrant knob (7) to center bubble of level vial (8). Record knob
reading of gunner's quadrant (4).
5
Continue rotation of the cross-level knob (1) in the same direction for one-quarter turn, reverse direction and continue
back to the intersection of the two scribed lines with no override. Check if bubble of level vial (8) of gunner's quadrant
(4) is centered. If not, rotate gunner's quadrant knob (7) of gunners quadrant (4) to center bubble. Note knob reading.
Backlash shall not exceed 1.0 mil as read from gunner's quadrant (4).
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