TM 9-2320-260-34-1
Table 2-1. Mechanical Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Step 2. Check crane turntable and bearing (para. 16-26).
Replace defective parts if mechanical blockage is evident (para. 16-26). Proceed to step 3 if
crane turntable and bearing are satisfactory.
Step 3. Replace swing hydraulic motor (para. 16-15).
END OF TESTING!
Step 1. Perform pressure check (TM 9-2320-260-20). Tee test gage into swing motor hydraulic
control line. Operate swing control valve.
a. Proceed to malfunction 67, steps 2 and 3 if hydraulic oil pressure is steady.
b. Proceed to step 2 if hydraulic line pressure is erratic.
Step 2. Tee test gage into control valve input pressure line. Confirm control valve input pressure.
a. Repair control valve if pressure is steady (TM 9-2320-260-20).
b. Proceed to step 3 if pressure is erratic or low.
Step 3. Check engine tachometer. Set throttle for 1200 rpm.
a. Replace hoist hydraulic pump if tachometer is steady (para. 16-24).
b. Proceed to malfunction 8 if tachometer is erratic.
END OF TESTING!
Step 1. Check for upper, internal, and lower rollers binding (TM 9-2320-260-20). Adjustor repair
roller assemblies if defective (para. 16-13).
Step 2. Perform pressure check (TM 9-2320-260-20). Tee into line at boom extension cylinder and
connect test gage.
a. Repair boom extension cylinder if pressure is sufficient (para. 16-20).
b. Perform malfunction 68, steps 2 and 3 if pressure is low or erratic.
END OF TESTING!
Perform pressure check (TM 9-2320-260-20). Tee into line at boom extension cylinder and connect
test gage.
a. Perform malfunction 69, step 1.
b. Repair boom extension cylinder if pressure is sufficient (para. 16-20).
c. Perform malfunction 68, steps 2 and 3 if pressure is low or erratic.
END OF TESTING!
Perform pressure check (TM 9-2320-260-20), Pay out some slack in hoist winch cable. Tee test gage
in wind-in winch hydraulic line. Operate winch to wind in cable.
a. Replace hoist winch hydraulic motor if pressure is sufficient and steady (para. 16-15).
b. Proceed to malfunction 68, steps 2 and 3 if pressure is low or erratic.
END OF TESTING!
