TM 9-2350-256-34-2
Table2-3. Troubleshooting-Continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
MAIN WINCH CIRCUIT (MAIN HYDRAULIC SYSTEM)--Continued
WARNING
Test components must be capable of withstanding a working pressure of 1950-2050 psi (step 7 only).
NOTE
After performing main hydraulic pump test, return all plumbing to original configuration.
Step 7.
Test main hydraulic pump. Remove check valve and tee between hose no. 4A and 4B. Install main
hydraulic pump pressure tester kit (Item 14, Table 2-1) between hose no, 4A and hose no. 4B. Install
test pressure gage in tee.
CAUTION
Make sure that the load valve is in full open position before performing test.
When performing main hydraulic pump pressure test, do not restrict oil flow
beyond operating pressure.
With main engine operating at 1800 rpm, operating pressure should be 1950-2050 psi
when restricting flow using load valve.
After testing, remove hose no. 413 from pump port no. 1. Remove pilot-operated
relief and unloading valve assembly from pump port no. 44. Install hose no. 4B on
pump port no. 44.
With main engine operating at 1800 rpm, operating pressure should be 1950-2050 psi
when restricting flow using load valve.
a.
Remove mechanical transmission and main hydraulic pump assembly. Refer to TM. 9-2350-256-
34-1, Medium Recovery Vehicle, M88A1.
b.
Replace main hydraulic pump. Refer to paragraph 3-16.
Step 8.
Test for improperly adjusted pilot operated relief and unloadling 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 1950-2054 psi. For location of valve gage port, and adjusting screw, refer to
views B and C, fig. 3-22.
Step 9.
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.
Change 5 2-6.1
