Parker 700 Series - Page 6

Bulletin 1531-001/USA
Pump/Motor Division
700 Series Service Procedure
Parker Hannin Corporation
Hydraulic Pump/Motor Division
Greeneville, TN 37745 USA
6
Troubleshooting Checklist
Trouble
Oil Leakage
Signicant loss of
speed under load
Low mechanical
efciency or undue
high pressure
required to operate
motor
Cause
1. Hose ttings loose, worn
or damaged.
2. Motor section seal rings (7)
deteriorated by excess heat.
3. Tie bolt loose
4. Broken tie bolts.
5. Internal shaft seal worn or
damaged.
6. Worn shaft and internal seal.
1. Lack of sufcient oil supply.
2. High internal motor leakage.
3. Excessive heat.
1. Line blockage.
2. Internal interference.
3. Excessive binding or loading
in system external to motor.
1. Low ow output of pump.
2. Relief valve set incorrectly or
not closing completely.
Check & replace damaged "O"
Rings. Torque to manufacturer's
specications.
Replace oil seal rings. Correct heat
problem.
If bolts are loose because of
excessive pressures as indicated
by most or all being loose, replace
bolts & advise customer to correct
the pressure regulation.
Replace bolts.
Replace seal.
Replace shaft and seal.
(a) Check for faulty relief valve
and adjust/replace as required.
(b) Check for/repair worn pump.
(c) Check for and use correct
oil for temperature of
operation. Check reservoir
uid level.
Replace worn IGR™ set.
Locate excessive heat source
(usually a restriction or lack of an
oil cooler) and correct.
Locate blockage source and repair
or replace.
Disassemble motor, identify and
remedy cause.
Locate source and eliminate
cause.
Repair or replace worn pump.
Reset relief, look for contamination
or replace.
Remedy
Lack of pressure
CAUTION
Seals in the system will shrink, harden or crack if uid tem-
peratures exceed 180˚F (82.2˚C), resulting in loss of ability to
seal.