5.2 Dump Valve Pendant
The pump will run and the cylinder will advance when the
pendant button is pressed.
Releasing the button will stop the pump. The cylinder will
retract automatically.
5.3 Pressure Switch Pumps (PES Models)
These pumps shut off when a preset pressure is reached
and turn on when pressure loss occurs. To set the desired
pressure, follow these steps:
1. Loosen the setscrew with a #10 Allen wrench.
2. Using a screwdriver, turn the adjustment screw
clockwise to raise and counterclockwise to lower the
actuation pressure.
3. Tighten the setscrew.
4. Run the pump to verify the pressure settings.
Pressure switch pumps are supplied with a pressure
gauge and with a manual valve for advancing and
retracting the cylinder(s).
5.4 Relief Valve Adjustment
Hushh® Pumps are equipped with two relief valves. One
is a factory set safety relief, which must not be adjusted or
repaired, except by an Authorized Enerpac Service
Center. The other relief valve can be adjusted as follows:
1. Install a gauge on the pump.
2. Start the pump to allow the oil to warm.
3. Remove the plug
from the side of the
reservoir
(see
Figure 16). Insert a
3/16
inch
hex
wrench
in
the
adjusting
screw,
located inside the
plug opening. Shift
the valve and build
pressure
in
the
system. Turn the
adjusting
screw
counter-clockwise
to
decrease
pressure
and
clockwise to increase pressure.
NOTE:
The adjustable relief valve should never be
bottomed out, or premature wear of the safety relief valve
will result. To get the most accurate setting, decrease the
pressure to a point below the final setting and then slowly
increase the pressure until it reaches the final setting.
4. Shift the valve to the neutral position, allowing the
system pressure to return to 0 psi.
5. Recheck the final pressure setting by shifting the
valve and pressurizing the system.
6.0 MAINTENANCE
Frequently inspect all system components for leaks or
damage. Repair or replace damaged components.
6.1 Check Oil Level
Check the oil level of the pump prior to start-up, and add
oil, if necessary, by removing the oil level gauge. Always
be sure cylinders are fully retracted before adding fluid to
the reservoir.
6.2 Change Oil and Clean Reservoir
Completely drain and clean the reservoir every 250 hours,
or more frequently if used in dirty environments.
NOTE: This procedure requires that you remove the pump
from the reservoir. Work on a clean bench and dispose of
used oil properly.
1. Unscrew the 10 bolts holding the coverplate to the
2. Pour all oil out of the reservoir.
3. Thoroughly clean the reservoir with a suitable
4. Unscrew the bolt holding the oil filter screen and
5. Reassemble the pump and reservoir, installing a new
6. Fill the reservoir with clean Enerpac hydraulic oil. The
6.3 Changing the (optional) Filter Element
A suction line filter may be ordered as an accessory to the
pump. The filter element should be replaced every 250
hours, or more frequently in dirty environments. The filter
manifold is equipped with a 3 psi (0,2 bar) bypass to
prevent cavitation if filter plugging occurs. Filter element
replacement part number is PFE-250.
Figure 16
6
reservoir and lift the pump unit out of the reservoir. Be
careful not to damage the filter screen.
cleaning agent.
remove the screen for cleaning. Clean the screen with
solvent and a soft brush. Reinstall the screen.
reservoir gasket.
reservoir is full when oil level is 1 inch (2.5 cm) below
the reservoir cover.