TM 9-2350-256-34
0012 00
CORRECTIVE ACTION Continued
11. Inspect APU emergency winch control valve lever for improper position.
a.
Place APU emergency winch control valve lever in CLOSED position.
WARNING
Main winch must be in high range (step 12 only).
12. Test for faulty pilot operated relief and unloading valve. Attempt operation of spade and winches.
If winches operate, but spade and boom fail to operate, it indicates a faulty pilot operated relief and
unloading valve. Shift main winch into high range and inhaul cable completely (clevis contacting front
of plate). Continue holding main winch control lever in this position and attempt to operate boom
combination control valve lever. Release both levers to neutral and operate boom combination control
valve lever.
a.
If boom does not function, replace pilot operated relief and unloading valve (WP 0051 00).
13. Test for boom combination control valve failure. Install pressure gage in pilot-operated relief and
unloading valve gage port. If, when actuating spade combination control valve lever, operating
pressure (19502050 psi [13,44514,135 kPa]) is recorded on pressure gage, but when actuating
boom combination control valve lever, no pressure is recorded on gage, it indicates a faulty boom
combination control valve. For location of valve gage port, refer to WP 0065 00.
a.
Replace boom combination control valve (WP 0051 00).
14. Test for restricted hydraulic hose or flow regulator. Install pressure gage in pilot operated relief
and unloading valve gage port. If, when actuating boom combination control valve lever, operating
pressure [19502050 psi (13,44514,135 kPa]) is recorded on pressure gage, it indicates valve is
functioning properly. Inspect for restricted hydraulic hose or obstruction in flow regulator. For
location of valve gage port, refer to WP 0065 00.
a.
Replace any restricted hydraulic hose (TM 9-2350-256-20).
b.
Remove any obstruction or replace flow regulator (WP 0065 00).
15. Inspect for mechanical failure of boom or hydraulic cylinder attaching pins.
a.
Replace any damaged pins (WP 0068 00).
16. Test for improperly adjusted pilot operated relief and unloading valve. Install test gage in valve port.
With engine operating at 1800 rpm, and spade in stowed position, place spade combination control
valve lever in RAISE position and adjust relief valve.
a.
Adjust relief pressure to 19502050 psi (13,44514,135 kPa). For location of valve gage port and
adjusting screw, refer to WP 0065 00.
17. Inspect for mechanical binding of boom and cylinder mounting pins.
a.
Replace any broken or damaged pins (WP 0068 00).
18. Inspect hydraulic hoses and connections for oil leaks.
a.
Repair leaks or replace hydraulic hose (refer to TM 9-2350-256-20).
19. Test for boom combination control valve failure. Install pressure gage in pilot operated relief and
unloading valve gage port. If, when actuating spade combination control valve lever, no pressure is
recorded on gage, it indicates a faulty boom combination control valve. For location of valve gage port,
refer WP 0065 00.
a.
Replace boom combination control valve (WP 0079 00).
0012 00-3
