TM-9-2320-361-20

2-1/2-TON, 6x6, M44A2 SERIES TRUCKS (MULTIFUEL)

TECHNICAL MANUAL; UNIT MAINTENANCE

OCTOBER 1991

TM-9-2320-361-20 - Page 149 of 1207

TM 9-2320-361-20

Table 2-3. Compressed Air and Brake System Troubleshooting (Contd).

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

Test 2. Check air pressure supply in protection valve (2).

Step 1. Stop engine and open all draincocks (TM 9-2320-361-10) until brake system air pressure is

vented.

Step 2. Disconnect air brake supply hose (4) from safety protection valve elbow (3).

Step 3. Remove elbow (3) from safety protection valve (2).

Step 4. Install tee (6) in safety protection valve (2).

Step 5. Connect air brake supply hose (4) to tee (6) and connect test gage (5) to tee (6).

NOTE

Service brake air pressure and airbrake hand control air pressure

must not be checked at the same time.

Air pressure must be held and maintained for pressure to

equalize in air hydraulic cylinder with air system pressure.

Step 6. Direct assistant to fully apply and hold service brakes or pull down on airbrake hand

control.

Step 7. Check test gage (5) reading.

a. If readings are very low or build up very slowly, check all lines for bends, kinks, or

restrictions. Repair or replace damaged lines (TM 9-243).

b. If test gage (5) reads zero when service brakes are applied, replace air-hydraulic

cylinder (1) (para. 8-11).

c. If test gage (5) reads zero when airbrake hand control is applied, replace airbrake hand

control (para. 8-21).

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