Enerpac P-392FP - Manual (Page 3)

3
5.2 Using Two-Speed Pumps
These pumps provide 2-stage flow. Under no-load, the pump
operates in the high flow first stage for rapid advance. When
the load is contacted, the pump automatically shifts to the
second stage for building pressure.
NOTE: For best performance, operate pump handle at
moderate speed during the high flow first stage. Rapid handle
speed in the first stage will prevent the pump from delivering
full volume of oil.
5.3 Single-Acting Applications with Release Valve
1. Close release valve by turning clockwise, as shown in
Figure 3.
CAUTION: Close release valve finger tight ONLY.
Using tools on release valve can damage it and
cause the pump to malfunction.
2. Operate pump handle to deliver hydraulic power to system.
Pressure will be maintained until release valve is opened.
3. Open release valve (turn counter-clockwise) to release
pressure, allowing oil to flow back to the reservoir.
5.6 Relief Valve Adjustment
All pumps contain a factory set relief valve to prevent over-
pressurization of the system. Lower pressure settings can be
obtained. Contact your Authorized Enerpac Service Center.
6.0 AIR REMOVAL
Removing air from the hydraulic system will help the cylinder to
advance and retract smoothly (see figure 4).
6.1 Pump With Single-Acting Cylinder (A)
1. Vent pump reservoir (for vented pumps only) and close
release valve.
2. Position pump at higher elevation than cylinder.
3. Position cylinder with the plunger end down (up if using pull
cylinder). See Figure 4 below.
4. Operate pump to fully extend the cylinder (retract if using
pull cylinder).
5. Open release valve to retract cylinder (extend if a pull
cylinder). This will force the trapped air to move up to the
pump reservoir.
6. Repeat the above steps as necessary.
7. Add oil if necessary. See paragraph 7.1 (page 3)
8. Return vent/fill cap to operating position.
7.0 MAINTENANCE
Use only Enerpac hydraulic oil with these pumps to promote
long pump life and to protect your warranty. Viton and EPR seal
kits are available for some hand pumps. Contact your Enerpac
representative for more information
7.1 Adding oil to pump
Check oil level regularly.
WARNING: Always add oil with cylinders fully
retracted (extended if pull cylinders) or the system
will contain more oil than the reservoir can hold.
1. Remove vent/fill cap from reservoir.
2. Fill reservoir only to level mark shown on pump.
3. Remove air from system if necessary. See page 6. Recheck
oil level after removing air.
4. Return vent/fill cap to proper position.
NOTE: Non-vented hand pumps require air in the reservoir to
function properly. If the reservoir is completely filled, a vacuum
will form preventing oil from flowing out of the pump.
7.2 Keeping Oil Lines Clean
When coupler halves are disconnected, always screw on dust
caps. Use every precaution to guard unit against entrance of
dirt because foreign matter may cause pump, cylinder, or
valve failure.
7.3 Lubricating the Pump
To extend pump life and improve performance, lubricate the
beam pin (A), cross pin (B), and piston head (C) regularly, using
roller bearing grease. See Figure 5 on page 4.
Release valve
Figure 3
AIR
Figure 4