Pump Making Noise

HYDRAULIC

REMEDY

TROUBLESHOOTING

CAUSE

1. Pump must receive intake oil freely or cavitation will

A. Pump

result. Drain system, and clean intake line, intake pipe,

and replace filter.

Pump Making Noise

2. Test by pouring oil on joints and around drive shaft.

1. Partially clogged intake

Listen for change in operation. Tighten joints affected

and replace pump drive.

2. Air leak at pump intake piping joints or

pump shaft packing.

Pump Not Delivering Oil

1. Must be reversed immediately to prevent seizure.

check direction of drive rotation against proper pump

1. Pump drive in wrong direction of rotation

rotation as indicated by arrow on outer surface of ring.

2. Pump drive shaft coupling sheared

2. Remove pump, and determine damage to pump

cartridge. Replace needed parts. Check engine high

3. Fluid intake pipe blocked or oil viscosity

idle to determine whether it is higher than

too heavy to pick up prime

recommended.

4. Air leaks at intake. Pump not priming

3. Drain complete system. Add new fluid of proper

viscosity. Check all filters for dirt and sludge.

B. Manual Control Valve

4. Circuit must be tested at input connections.

Oil Leaks At Either Spool End

Determine where air is being drawn into line connections

and tighten. Check intake opening in reservoir. Check

1. Defective oil seal

minimum drive speed which may be too slow to prime

the pump.

2. Valve spool or body scored

1. Replace seal. If leaking continues, replace valve

spool or valve assembly as necessary.

2. Replace valve spool or assembly as necessary.

B-156