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 190 of 828

TM 9–2350–311–20–2

Change 2

3–79

f.

RAMMER HYDRAULIC SYSTEM — CONTINUED

(1)

RAMMER DOES NOT OPERATE.

INITIAL SETUP

Tools

Artillery and turret mechanic’s tool kit

(SC 5180–95–CL–A12)

Equipment Condition

Vehicle MASTER switch to ON (TM 9–2350–311–10)

CAB POWER switch to ON (TM 9–2350–311–10)

Replace actuating valve

(para 7–4).

1.

Stow rammer.

2.

Slowly operate actuating valve repeatedly,

observing rammer, rammer hoses, and pressure

gage.

Is hydraulic pressure increase evident in rammer and hoses

while hydraulic pressure drops slightly?

yes

no

A

yes

no

Troubleshoot cab hydraulic

system (para 3–3e.).

B

yes

no

Adjust blocking valve (para 7–3).

Is malfunction corrected?

Return to normal operation.

CONTINUED ON NEXT PAGE

C

Check hydraulic pressure at pressure gage (TM

9-2350-311-10).

Is hydraulic pressure normal?

ACTUATING VALVE

RAMMER

CYLINDER

HOSES, TUBES, AND FITTINGS

BLOCKING VALVE