Change Oil And Clean Reservoir; Motor Brush Replacement; Check Oil Level - Enerpac ZU4 Serie Instructions

C. "LO PRESS" Menu (Firmware 5.6 and later)
Screen 23
SET
LO PRESS
OFF
(See Screen 23.) This screen allows the operator to set the low-pressure
limit for the pump to re-energize the motor / electric valve. Maximum
value is 50 psi less than the current HI PRESS value. When LO PRESS
is set to a value higher than OFF, the pump will operated like a pressure
switch pump, de-energizing the motor / electric valve at the HI PRESS
value and re-energizing the motor / electric valve at the LO PRESS value.
For an additional notice to the operator, when pump is latched into in this
"pressure switch" mode, the operating menu text will change to "AUTO
ON" and the LCD back light will flash.
Caution: Setting the LO PRESS value too close to the
HI PRESS value may cause the pump to cycle on and
off too often. Frequent starting and stopping of the
motor will increase wear and reduce the life of the pump. Use
appropriate valving in the hydraulic circuit to ensure that the
pump does not cycle on and off more than 3 times per minute.
D. "Calibration " Menu
Screen 24
SET
CAL PT A
0
(See Screen 24.) This screen allows the operator to adjust the pressure
value shown on the LCD to match a master gauge. To access this
menu:
Firmware 5.5 and earlier – go to "Set Pres" menu
Firmware 5.6 and later - go to "UNITS" menu
Then press and hold the ON/OFF button in for 7 seconds, ENTRY
CODE will appear. Then press and hold both Down-Arrow & Up-Arrow
buttons for 7 seconds. See tables 2 "Z-Class Pump Calibration" for
adjustment steps.
7.0 MAINTENANCE
Frequently inspect all system components for leaks or damage.
Repair or replace damaged components. Electrical components,
for example, the power-cord, may only be repaired or replaced by
a qualified electrician, adhering to all applicable local and national
codes.

7.1 Check Oil Level

Check the oil level of the pump prior to start-up, and add oil, if
necessary, by removing the fill port cap. Always be sure cylinders
are fully retracted before adding fluid to the reservoir. See Figure 2.
PSI

7.2 Change Oil and Clean Reservoir

Enerpac HF oil is a crisp blue color. Frequently check oil condition
for contamination by comparing pump oil to new Enerpac oil. As
a general rule, 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
according to local codes.
1. Unscrew the 13 bolts holding the coverplate to the reservoir
and lift the pump unit out of the reservoir. Be careful not to
damage the filter screen.
2. Pour all oil out of the reservoir.
3. Thoroughly clean the reservoir and reservoir magnet with a
suitable cleaning agent.
4. Remove the pick-up filter screen for cleaning. (Do not pull on
the screen or the bottom of the intake to avoid possible
damage.) Clean the screen with solvent and a soft brush.
Reinstall.
5. Reassemble the pump and reservoir, installing a new
reservoir gasket.
6. Fill the reservoir with clean Enerpac hydraulic oil. The
reservoir is full when oil level is in middle of the sight gauge
(see figure 4).
7.3 Changing the Filter Element (optional)
A return 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 25 psi (1,7 bar) bypass to prevent over pressure rupture if filter
plugging occurs. Filter element replacement part number is PF-25.

7.4 Motor Brush Replacement

To prevent motor damage, the ZU4 motor brushes incorporate
an automatic motor stop when one of the brush carbons wear to
a length of 0.25" [6 mm]. Inspect both brushes.
1. Disconnect pump from electrical power.
DANGER: To avoid possible electrocution, pump must
be completely disconnected from electrical power
before brush servicing is attempted.
2. Remove both brush caps (A) by deflecting the brush cap
latch (B) and gently prying outward (see Figure 11).
Figure 11, Brush Cap Removal
A. Brush Cap
3. Remove motor brushes by turning black cap counter-
clockwise.
4. Replace both brushes and reverse procedure to reassembly.
10
B. Brush Cap Latch