TM 9-2320-272-24-2
Table 4-1. Mechanical Troubleshooting (Contd).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Step 10. Inspect hydraulic line between control valve and hydraulic reservoir for kinks, bends, or
restrictions.
If bends, kinks, or restrictions are present, replace hydraulic line (para. 4-147).
Step 11. Inspect dump cylinder hydraulic lines for bends, kinks, or restrictions.
a. If bends, kinks, or restrictions are present, replace dump cylinder hydraulic lines
(para. 4-147).
b. If bends, kinks, or restrictions are not present, replace dump cylinder (para. 5-105).
END OF TESTING!
MEDIUM WRECKER CRANE
When adjusting pressure relief valve settings, set at specified
pressures only. Failure to do so could result in injury to
personnel or damage to equipment.
Do not loosen or remove any lines or hoses while the engine is
running. Doing so may result in injury to personnel.
60. BOOM DOES NOT RESPOND PROPERLY WHEN BOOM CONTROL VALVE LEVERS ARE MOVED
Step 1. Visually inspect reservoir filter.
If damaged, replace reservoir filter (para. 5-336).
Step 2. Check hydraulic oil for contamination (LO 9-2320-272-12).
Clean hydraulic oil as required (TB 43-0211).
Step 3. Ensure hydraulic reservoir is filled to proper level (LO 9-2320-272-12).
Step 4. Ensure PTO lever fully engages and disengages PTO (TM 9-2320-272-10).
a. If PTO lever does not engage PTO, check control cable adjustment and adjust as
required (para. 4-205).
b. If control cable is adjusted and lever will not engage PTO, replace transfer case PTO
(para. 4-207).
Step 5. Ensure hand throttle cable is adjusted properly.
Adjust hand throttle cable as required (para. 3-45).
Step 6. Ensure engine governor maintains an engine speed of 1,200-1,300 rpm, as indicated by
vehicle tachometer when PTO is engaged, transfer case is in neutral, transmission selector
is in drive 5th position, and hand throttle is pulled out fully.
a. If governor does not operate properly, ensure fuel pump governor lever is pushed into
the full fuel position by the air-actuated piston. Adjust lever adjustment screw and/or air
cylinder piston as required (para. 4-35).
b. If air cylinder piston does not extend, inspect air system components. If air system
components are damaged, replace (chapter 4, section X).
c. If air cylinder operates, but governor speed cannot be adjusted, replace fuel pump
(para. 4-35 or 4-57).
Step 7. Inspect hydraulic pump, motors, valves, lines, and hoses for leaks or loose connections.
Tighten any loose connections and repair any leaks (TM 9-243).
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