Greenlee 980 - Page 13

Greenlee / A Textron Company 13 4455 Boeing Dr. • Rockford, IL 61109-2988 USA • 815-397-7070
980 Hydraulic Power Pump
Troubleshooting—Hydraulic Pump (cont’d)
Pump will not build enough High-pressure system is faulty. See Hydraulic Schematic (5) and refer
pressure to complete the job. to Figure A5-1 in the Repairs section of
Ram advances slowly. this manual.
System has an external hydraulic leak. Visually inspect hoses, connectors
and fittings for leaking hydraulic fluid.
Replace faulty components.
Pilot-operated valve will not close. See “Troubleshooting—Pilot-Operated
Valve” at the end of this Troubleshooting
section.
Low-pressure system is at fault. Find “Low-pressure system partial or
complete failure” under Probable
Causes in this Troubleshooting section.
At high-pressure inlet, the check ball See Check Ball Travel at High Pressure
has too much travel. Inlet, Figure A5-1. If the seats are
leaking, see Ball Seat Refinishing,
Figure B2 in the Repairs section of this
manual.
The high-pressure piston is stuck. Disassemble, clean, and inspect the
high-pressure bushing (75) and
high-pressure piston (76). Replace
parts as necessary.
Internal hydraulic fluid leak. Inspect and replace as necessary:
O-ring Plug (68)
Cavity Insert (74)
High-Pressure Bushing (75)
High-Pressure Relief Valve (72)
High-pressure relief valve failure. Readjust, re-seat or replace valve (72).
PROBLEM PROBABLE CAUSE POSSIBLE REMEDY