Enerpac ST-121 - Manual (Page 10)

MAINTENANCE
Maintenance is required when wear or leakage is noticed. Occasionally inspect all
components to detect any problem requiring service and maintenance. Enerpac
offers ready-to-use Repair Parts Kits. Repair Parts Sheets are available with
assembly drawing and parts list. Contact Enerpac.
IMPORTANT: Consult the Repair Parts Sheet for service information as to correct
assembling and disassembling. Incorrect maintenance and service such as wrong
torque values may cause product malfunctions and/or personal injury.
TROUBLESHOOTING
The following information is intended to be used only as an aid in determining if a
problem exists. For repair service, contact your Distributor or Authorized Enerpac
Service Center.
Problem Possible Cause Solution
1. Cylinder will not
clamp/unclamp.
A. pump release valve open
B. no oil in pump reservoir
C. air in system
D. couplers not fully
tightened
E. blocked hydraulic line
F. spring broken in cylinder
A. close pump release valve
B. fill pump reservoir
C. remove air from hydraulic system
D. retighten couplers
E. check valves, fittings, and tubing
F. replace spring
2. Cylinder advances
part way.
A. oil level in pump too low
B. plunger binding A. fill pump reservoir
B. replace damaged parts
—refer to Repair Parts Sheet
3. Cylinder
clamps/unclamps
slower than normal.
A. leaking connection
B. restricted hydraulic line
C. pump malfunction A. retighten fittings, couplers,
and tubing
B. check valves, fittings, and tubing
C. refer to pump Instruction Sheet
4. Cylinder
clamps/unclamps
but will not hold
pressure.
A. seals damaged
B. leaking connection
C. pump malfunction A. replace seals
—refer to Repair Parts Sheet
B. retighten fittings, couplers,
and tubing
C. refer to pump Instruction Sheet
5. Cylinder leaks oil. A. seals damaged
B. plunger worn or damaged
A. replace seals
—refer to Repair Parts Sheet
B. replace damaged parts
—refer to Repair Parts Sheet
6. Clamp arm does
not make swing
movement.
A. clamp arm loose
B. plunger damaged A. reposition and tighten clamp arm
—see Attaching Clamp Arm
on page 7
B. replace damaged parts
—refer to Repair Parts Sheet
10