TM-9-2320-272-24-3

TRUCK, 5-TON, 6X6, M939, M939A1, AND M939A2 SERIES TRUCKS (DIESEL)

TECHNICAL MANUAL; UNIT, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL; VOLUME 3 OF 4

JUNE 1998

TM-9-2320-272-24-3 - Page 320 of 799

TM 9-2320-272-24-3

Section X. COMPRESSED AIR AND BRAKE SYSTEM MAINTENANCE

4-107. COMPRESSED AIR AND BRAKE SYSTEM MAINTENANCE INDEX

PARA.

NO.

4-108.

4-109.

4-110.

4-111.

4-112.

4-113.

TITLE

Brake Pedal (Treadle) Valve Repair

Relay Valve Repair

Parking and Service Brakedrum Repair

Parking and Service Brakeshoe Repair

Front Brake Actuator Repair

Rear Brake Actuator Repair

PAGE

NO.

4-584

4-590

4-592

4-594

4-596

4-600

4-108. BRAKE PEDAL (TREADLE) VALVE REPAIR

THIS TASK COVERS:

a. Disassembly

b. Cleaning and Inspection

c. Assembly

INlTlAL SETUP:

APPLlCABLE MODELS

All

TOOLS

REFERENCES (TM)

TM 9-2320-272-24P

General mechanic’s tool kit (Appendix E, Item 1)

EQUIPMENT CONDITION

MATERIALS/PARTS

Valve repair kit (Appendix D, Item 706)

O-ring (Appendix D, Item 452)

Pedal mounting plate gasket

(Appendix D, Item 209)

Lint-free cloth (Appendix C, Item 21)

Brake pedal (treadle) valve removed (para. 3-197).

GENERAL SAFETY INSTRUCTIONS

Spring tension under valve retainer could cause

flying parts.

NOTE

Do not perform this procedure unless valve repair kit is available.

a. Disassembly

1.

Remove three screws (9), mounting plate (3), and gasket (2) from valve body (1). Discard gasket (2).

2.

Remove breather (6), plunger (8), and O-ring (7) from mounting plate (3). Discard O-ring (7).

3.

Loosen locknut (4) and remove stopscrew (5) from mounting plate (3).

4-584