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 567 of 828

TM 9–2350–311–20–2

14–3

14–1 GUNNER’S ESCAPE HATCH (UNMODIFIED)

This task covers:

a.

Removal

b.

Disassembly

c.

Assembly

d.

Installation

INITIAL SETUP

Tools

Artillery and turret mechanic’s tool kit

(SC 5180–95–CL–A12)

Torque wrench (item 18, Appx H)

Materials/Parts

Adhesive, type I (item 2, Appx D)

Cotter pins (2) (item 38, Appx G)

Seal (item 110, Appx G)

Sealing compound (item 30, Appx D)

Sealing compound, No. 2 (item 27, Appx D)

Preformed packing (item 50, Appx G)

Primer, paint (item 24, Appx D)

Retaining ring (item 20, Appx G)

Retaining rings (2) (item 21, Appx G)

Self-locking nut (item 185, Appx G)

Self-locking nut (item 35, Appx G)

Personnel Required

2

a.

Removal

1

Open gunner’s escape hatch (1) from inside cab, raise to upright position and hold at 90

°

to cab roof.

2

Remove two machine screws (2).

3

Close gunner’s escape hatch (1).

4

Remove plug (3) and flat washer (4).

5

Drive torsion bar (5) from torsion bar anchor (6) in retainer weldment (7). Remove torsion bar with attached

parts.

6

Remove tube (8), retaining ring (9), and retaining plate (10) from torsion bar (5). Discard retaining ring.

7

Lift off gunner’s escape hatch (1) for disassembly. Removal of torsion bar anchor (6) from retainer weldment

(7) is not required.

1

9

10

2

5

8

7

4

3

6