Table 2-3. Troubleshooting--Continued
TEST OR INSPECTION
HOISTING BOOM CIRCUIT (MAIN HYDRAULIC SYSTEM)-Continued
Inspect main hydraulic pump for broken or damaged shaft coupling.
a. Remove mechanical transmission and main hydraulic pump assembly. Refer to TM 9-2350-256-34-1, Medium
Recovery Vehicle, M88A1.
b. Repair or replace shaft coupling. Refer to paragraph 3-16.
Test for improperly adjusted pilot-operated relief and unloading valve. Install test gage in valve gage 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.
Adjust relief pressure to 1950-2050 psi For location of valve gage port, and adjusting screw, refer to views B and
C, figure 3-22.
Inspect all hydraulic hoses and connections for visible indication of oil leaks.
Repair leaks or replace hydraulic hose. Refer to TM 9-2350-256-20, Medium Recovery Vehicle, M88A1.
Inspect system selector lever for improper position.
Place system selector lever in MAIN position.
Inspect auxiliary power unit (APU) emergency winch control valve lever for improper position.
Place auxiliary power unit (APU) emergency winch control valve lever in CLOSED position.