TM-9-2350-311-20-2

HOWITZER, MEDIUM, SELF-PROPELLED, 155MM; M109A2, M109A3, M109A4 AND M109A5

TECHNICAL MANUAL; UNIT MAINTENANCE MANUAL FOR CAB, ARMAMENT, SIGHTING AND FIRE CONTROL, ELEVATING AND TRAVERSING SYSTEMS AND ASSOCIATED COMPONENTS

DECEMBER 1993

TM-9-2350-311-20-2 - Page 556 of 828

TM 9–2350–311–20–2

12–14

Change 2

12–3 CUPOLA COVER, BODY, AND HANDLE — CONTINUED

e.

Adjustment

1

To adjust anchor/torsion bar assembly on cupola cover (1), insert new spacer plate(s) (6) as required. Pro-

vide a 0.016 + 0.063 inch (0.406 + 1.6 mm) clearance between spring ends and anchor.

2

Insert new spacer ring(s) (7) as required. Provide a 0.005 + 0.200 inch (0.127 + 5.08 mm) clearance be-

tween tube end and cover hinge.

3

Insert new flat washer(s) (9) as required. Center hatch in cupola body within 0.047 inch (1.2 mm).

4

Insert new flat washers(s) (25) as required. Provide spring washer (30) depression of approximately 0.031

inch (0.79 mm) in UNLOCK position.

NOTE

Step 5 pertains to commander’s cupola assemblies which have been modified and use the knob

latch assembly.

5

To adjust catch/latch assembly on cupola cover (1) when secured in open position, insert shims (11.4) as

required. Provide a 0.06 to 0.12 inch (1.524 to 3.048 mm) clearance between end of plunger of latch assem-

bly (22.4) and to back of slot in catch (11.3).

1

6

7

9

30

25

11.4

11.3

1

22.4