Hydraulic Pump - Wittke STARLIGHT Maintenance Manual

82 Hydraulic System
 Clean the strainer inside the hydraulic tank after the first 50 hours of use, and once a year
afterwards (see Cleaning the Strainer on page 101).
 Hydraulic oil must be replaced at least once a year, or when contaminated (see Changing
Hydraulic Oil on page 106).
N : The ball valve (or shut-off valve) on the hydraulic tank [see Figure 7-14] must be completely
OTE
open before engaging the pump or starting the engine.
Labrie Enviroquip Group requires that the hydraulic fluid and return line filter be changed and that
the strainer be cleaned before changing the hydraulic pump.
Manufacturer's warranty on hydraulic pumps provided or sold by Labrie Enviroquip Group could be
declared void if the hydraulic fluid and return line filter are not changed, and if the strainer is not
cleaned prior to replacing the hydraulic pump.
It is therefore mandatory to change the return line filter and the hydraulic fluid and to clean the
strainer as per the recommended maintenance schedule mentioned above. Hydraulic fluid
contamination will severely damage hydraulic components.
It is recommended to have the hydraulic fluid tested and analyzed by a lab to prevent hydraulic
system or pump breakdown. This will also optimize the frequency of hydraulic fluid changes.
N : Evidence of maintenance and/or fluid samples could be requested when filing warranty claims
OTE
concerning the hydraulic system or pump.

Hydraulic Pump

Oil supply from the tank enters the hydraulic pump (see Figure 7-1) through the suction line.
Pressurized oil exits the hydraulic pump through the pressure line directly to the main valve. A return
line exits the hydraulic pump and runs excess oil back to the oil tank.
The pump is activated by an electric solenoid valve mounted on the pump (see Figure 7-2). The
electrical signal that activates the solenoid is sent by the pump switch on the control panel.
Figure 7-1 Hydraulic pump