TM 9-2320-272-24-2
Table 4-1. Mechanical Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
61. ALL BOOM CONTROLS OPERATE ABNORMALLY
Step 1. Perform malfunction 60, steps 1 through 7.
Step 2. Check reservoir return lines for blockage.
a. If blockage is found, clear lines.
b. If no blockage is found, replace boom control valve (para. 4-201).
Step 3. Check boom relief pressure (malfunction 60, step 11).
END OF TESTING!
62. WING CONTROL OPERATES ABNORMALLY; ALL OTHER CONTROLS OPERATE NORMALLY
Step 1. Perform malfunction 60, steps 1 through 7.
Step 2. Check swing motor hydraulic lines for blockage.
a. If blockage is found, clear lines.
b. If no blockage is found, replace swing motor (para. 4-199).
Step 3. Check swing control operation.
If swing control operates abnormally, replace boom control valve (para. 4-201).
Step 4. Check boom relief pressure (malfunction 60, step 11).
END OF TESTING!
63. CROWD CONTROL OPERATES ABNORMALLY; ALL OTHER CONTROLS OPERATE NORMALLY
Step 1. Perform malfunction 60, steps 1 through 7.
Step 2. Check boom extension cylinder hydraulic lines for blockage.
a. If blockage is found, clear lines.
b. If no blockage is found, replace boom extension cylinder (para. 4-196).
Step 3. Check crowd control operation.
If crowd control operates abnormally, replace boom control valve (para. 4-201).
Step 4. Check boom relief pressure (malfunction 60, step 11).
END OF TESTING!
64. HOIST CONTROL OPERATES ABNORMALLY; ALL OTHER CONTROLS OPERATE NORMALLY
Step 1. Perform malfunction 60, steps 1 through 7.
Step 2. Check hoist winch motor hydraulic lines for blockage.
a. If blockage is found, clear lines.
b. If no blockage is found, replace hoist winch motor (para. 4-199).
Step 3. Check hoist control operation. If hoist control operates abnormally, replace boom control
valve (para. 4-201).
Step 4. Check boom relief pressure (malfunction 60, step 11).
END OF TESTING!
65. BOOM CONTROL OPERATES ABNORMALLY; ALL OTHER CONTROLS OPERATE NORMALLY
Step 1. Perform malfunction 60, steps 1 through 7.
Step 2. Check boom elevation cylinder hydraulic lines for blockage.
a. If blockage is found, clear lines.
b. If no blockage is found, replace elevating cylinders (para. 4-193).
Step 3. Check boom control operation. If boom control operates abnormally, replace boom control
valve (para. 4-201).
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