TM 5-3895-372-34
Table 2-2. Troubleshooting Procedures (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
6.
CONTROL VALVE HAS HIGH HANDLE LOAD:
Step 1.
Check for restriction "return" port or pressure on the return port due to valve
being installed incorrectly.
Remove the restriction or install valve correctly (para 3-14).
Step 2.
Check for bent detent disk gouging into top of housing.
Remove and flatten detent disk (para 3-13 and 3-14).
Step 3.
Check for dirt under thrust washer which lifts and cocks rotor.
Disassemble and clean valve (para 3-14 and 3-15).
Step 4.
Check for worn or missing stop pin on shaft which allows rotor to gouge into housing.
Disassemble and replace shaft pin (para 3-14).
Step 5.
Check for worn or brinelled or corroded groove in rotor and thrust washer causing
balls to bind.
Turn thrust washer over and surface grind worn side of rotor. Put shim under
thrust washer equal to material ground off rotor (fig. 3-3).
Step 6.
Check for pressure in excess of valve rating.
Adjust relief valve. (Refer to TM 5-3895-372-20.)
Step 7.
Check for worn lip off shear seal seat which would increase friction load.
Replace shear seal seat (para 3-13 thru 3-16).
Step 8.
Check for galling between the shear seal seat and rotor.
Grind and lap face of rotor and shear seal seat. Put shim under thrust washer
equal to material ground off rotor (para 3-13 thru 3-16).
7.
EXTERNAL LEAKAGE AROUND SHAFT OF CONTROL VALVE:
Step 1.
Check for worn shaft O-ring.
Replace shaft O-ring (para 3-13 thru 3-16).
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