TM 9-2320-260-20
Table 2-3. Compressed Air and Air-Hydraulic Brake System Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
I
CORRECTIVE ACTION
Step 3. Refer to malfunction 11 for insufficient or loss of air pressure.
Step 4. Check for leaks in brake lines.
a. Direct assistant to pump brakes.
b. If brake lines are leaking or darnaged, replace brake lines as required.
Step 5. Check for defective master cylinder.
a. Direct assistant to pump brakes.
b. Check master cylinder for leaks.
c. Remove dust boot from master cylinder.
If brake fluid leaks from dust boot area, replace master cylinder (para. 8-11).
Step 6. Check for defective air-hydraulic cylinder.
Replace air-hydraulic cylinder if insufficient braking continues after performing steps 1
through 5 (para. 8-14).
END OF TESTING!
4. BRAKES DRAG (ONE WHEEL)
Step 1. Check service brake adjustment (para. 8-9).
If adjustment does not solve problem, perform step 2,
Step 2. Remove wheel, hub, and service brakedrum (para. 9-4 or 9-5).
Step 3. Check for defective wheel cylinder.
a. Inspect wheel cylinder for leaks and darnage.
b. Replace wheel cylinder if leaking or damaged (para. 8-10).
Step 4. Check service brakeshoes for contamination.
Replace brakeshoes if contaminated by leaking brake fluid (para. 8-8).
Step 5. Check for restricted or darnaged brake line.
Clean or replace brake line if restricted or damaged.
END OF TESTING!
5. BRAKES DRAG (ALL WHEELS)
Step 1. Check brake pedal free travel (para. 8-17).
Adjust as necessary (para. 8-17).
Step 2. Check service brake adjustment (para 8-9).
If adjustment does not solve problem, perform step 3.
Step 3. Check for restricted or damaged brake line(s).
Clean or replace brake line(s) if restricted or darnaged.
Step 4. Check for defective master cylinder.
a. Direct assistant to pump brakes.
b. Check master cylinder for leaks.
c. Remove dust boot horn master cylinder.
Replace master cylinder if brake fluid leaks from dust boot area (para. 8-11).
Step 5. Check for defective air-hydraulic cylinder.
Replace air-hydraulic cylinder if brake drag continues after performing steps 1 through 4
END OF TESTING!
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