TM 9-2330-356-14
Take 4-9. Unit Troubleshooting (Con't).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
BRAKE SYSTEM (Con't)
7. GRABBING BRAKES (Con't).
Inspect for worn or loose brake linings.
Step 4.
If brake linings are worn within .030-inch of rivet heads, replaca brake shoes (para 4-33 or
4-34). If linings are loose, replace brake shoes.
Step 5.
Inspect for cracked, scored, or deformed brake drum.
Replace brake drum.
8. BRAKE DRAG (ONE OR MORE BRAKE DRUMS RUNNING HOT).
Step 1.
Check if brakes are adjusted too tightly (para 4-33 or 4-34).
AUTOMATIC ADJUSTERS NOT WORKING.
Test for leaking fail-safe chamber (para 4-39 or 4-40).
Step 2.
If fail-safe chamber is leaking, replace fail-safe chamber (para 4-39 or 4-40).
Check for broken brake shoe tension spring. Remove wheel and tire and brake drum (para 4-49) to
Step 3.
expose wheel brake.
If brake shoe tension spring is broken, replace the spring (para 4-33 or 4-34).
inspect for out-of-round drum.
Step 4.
Replace if out-of-found.
9. AUTOMATIC ADJUSTERS NOT WORKING (M967, M969, and M970 except M970 SN TC-0843, TC-0844,
and TC-103 thru TC-178).
Step 1.
Check if adjusting pawl is properly installed.
Install adjusting pawl properly (para 4-36).
step 2.
Check if pawl spring is collapsed or missing.
Replace pawl spring (para 4-36).
Step 3.
Check if adjusting bolt is frozen in adjusting sleeve.
Free bolt. Replace if necessary (para 4-36).
Step 4.
Check if detent spring is damaged and allowing adjusting bolt to rotate with sleeve.
Replace detent spring (para 4-36).
Check if adjusting plunger is in wrong position.
Step 5.
Adjusting plunger should beat leading edge of shoe. Install properly (para 4-36).
4-12
Change 3
