TM 9-1240-400-34&P
6
Adjust elevation machine thread plug (9) using a
screwdriver. Check the torque or backlash and if still
excessive, proceed to step 7.
7
Remove tapered pin (10), knob (1), and nonmetallic
washer (11) from worm shaft (12).
8
Adjust externally threaded ring (13) using spanner
wrench (8284045) to adjust torque or backlash.
9
Install nonmetallic washer (11) and knob (1) on
worm shaft (12) and secure with tapered pin (10).
CHECKING AND ADJUSTING ELEVATION KNOB TORQUEAND BACKLASH
1
Using torque wrench and torque adapter (8599909),
measure the torque required to turn elevation knob
(1). The torque shall be between 5.00 and 13.00 in.-
lb (0.57 and 1.47 N-m). If not, adjust according to
adjustment procedure. Refer to step 6.
2
Rotate elevation knob (1) in one direction to center
bubble in elevation vial (2).
3
Scribe a line on boss (3) and elevation knob (1).
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