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 275 of 828

TM 9–2350–311–20–2

5–19

NOTE

•

Perform step 5 for the M185 cannon assembly.

•

Perform step 6 for the M284 cannon assembly with plunger assembly 11580174.

•

Perform step 7 for the M284 cannon assembly with plunger assembly 11580469.

5

Install plunger assembly (7) and secure with two new lockwashers (6) and two cap screws (5).

6

Rotate plunger assembly (10) to release from cam plate (12). Be sure plunger assembly tip seats in narrow

slot of nut (8).

7

Rotate pin (13) from position B to position A to seat plunger assembly (14) tip in narrow slot of nut (8).

8

Depress detent (3) with punch.

9

Rotate breechblock (1) to UNLOCKED position.

10

Close breechblock (1), using one mechanic to move operating handle (2) to CLOSED position and the other

to support the breechblock.

1

3

2

LOCK

UNLOCK

10

M284 CANNON CONFIGURATION

8

Position A

Position B

Position C

“Pin”

13

14

PLUNGER ASSEMBLY 11580174

PLUNGER ASSEMBLY 11580469

M284 CANNON CONFIGURATION

7

12

PLUNGER ASSEMBLY

M185 CANNON CONFIGURATION

6

5