TM-9-2330-356-14

SEMITRAILER, TANK: 5000 GALLON, BULK HAUL, SELF LOAD/UNLOAD M967 AND M967A1; SEMITRAILER, TANK: 5000 GALLON, FUEL DISPENSING, AUTOMOTIVE M969 AND M969A1; SEMITRAILER, TANK: 5000 GALLON, FUEL DISPENSING, UNDER/OVERWING AIRCRAFT M970 AND M970A1

TECHNICAL MANUAL; OPERATOR’S, UNIT, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL

OCTOBER 1990

TM-9-2330-356-14 - Page 147 of 528

TM 9-2330-356-14

Table

4-9.

Unit Troubleshooting (Con't).

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

BRAKE SYSTEM (Con’t)

5.

NO BRAKES OR WEAK BRAKES.

Step 1.

Test for leaking air chamber diaphragm (para 4-37 or 4-38).

If air chamber is leaking, replace air chamber (para 4-37 or 4-38).

Step

2.

Inspect for grease on brake linings. Remove wheel and tire and hub and drum to expose wheel

brake (para 4-49). If grease is evident, inspect wheel seal for damage.

Replace brake shoes (para 4-33 or 4-34). If wheel seal is damaged, replace (para 4-49).

Step 3.

Inspect for worn brake linings.

If brake linings are worn within .030-inch of rivet heads, replace brake shoes (para 4-33 or

4-34).

Step 4.

Test relay emergency valve (para 4-44).

If there is leakage or hesitation in brake application or release, replace relay emergency

valve (para 4-44).

6.

SLOW BRAKE APPLICATION OR SLOW RELEASE.

Step 1.

Test for leaking air chamber diaphragm (para 4-37 or 4-38).

if air chamber is leaking, replace air chamber (para 4-37 or 4-38).

Step 2.

Check for broken brake shoe tension spring. Remove wheel and tire and brake drum to expose

wheel brake (para 4-49).

If brake shoe tension spring is broken, replace the spring (para 4-33 or 4-34).

Step 3.

Test relay emergency valve (para 4-44).

If there is leakage or hesitation in brake application or release, replace relay emergency

valve (para 4-44).

7.

GRABBING BRAKES.

Step 1.

Check for improperly adjusted brakes (para 4-33 or 4-34). Check automatic adjusters.

Adjust brakes (para 4-33 or 4-34).

Step 2.

Inspect for grease on brake linings. Remove wheel and tire and hub and drum (para 4-49) to

expose wheel brake. If grease is evident, inspect wheel Seal for damage.

Replace brake shoes (para 4-33 or 4-34). If wheel seal is damaged, replace (para 4-49).

Step 3.

Inspect for loose or worn wheel bearings.

If wheel bearings are loose, adjust to the proper preload (para 4-49). If they cannot be

adjusted properly, replace wheel bearings (para 4-49).

4-11