TM 9-1240-400-34&P
5-19.
FINAL INSPECTION INSTRUCTIONS (CONT).
MOUNTING M137 TELESCOPE MOUNT ON CROSS-LEVELING FIXTURE (CONT)
5
Position parallel bar (7) on top surface of upper
telescope mount subassembly at right angles to
locating pins (9). Level the top surface of the upper
telescope mount subassembly using the precision
level (8) positioned on top of parallel bar (7).
Surface should be horizontal in this plane within 0.5
mil. Use elevation knob (11) to level M137 telescope
mount.
INSPECTING AND ADJUSTING LEVEL BAR
1
Check level bar (1) by placing gunner's quadrant (2) on level bar (1). If reading is within 0.2 mil of zero elevation, bar
does not need adjustment. If reading is not within 0.2 mil of zero elevation, bar must be adjusted. Refer to steps 2
thru 5.
2
Carefully remove pin (3) from level bar (1) and bracket (4) with bracket removed from M137 telescope mount (5).
3
Place spring (6) between level bar (1) and bracket (4), and secure with capscrew (7) and convex washer (8).
4
With the cross-level and elevation test fixture and M137 telescope mount level in both directions, place the gunner's
quadrant (2) on level bar (1) and perform an end-for-end test on the quadrant. Adjust capscrew (7) for zero elevation
as read on gunner's quadrant.
5-56
