The number one enemy of hydraulic systems is contamination. When replacing a pump, all filters should be replaced or cleaned and the system oil checked for cleanliness. Replace dirty or contaminated oil. To not do so will increase wear on all components of the systemincluding hydraulic motors!
Pump rotation is extremely important. Pump damage will occur if the rotation is in the wrong direction. Rotation is designated by looking at the pump shaft end. EXAMPLE: With the shaft facing you and the gear drive on the top, the right side is the HIGH pressure side with CLOCKWISE ROTATION.
After filling the reservoir with clean oil and checking all fittings and connections, be sure the gate valve is open to the pump if the system has a valve. Many pumps have been ruined because someone forgot to open the suction side valve to the pump.
NOTE: Pump inlet oil temperature should not exceed 180 degrees Fahrenheit. The system also needs a 10 micron or finer return line filter to keep it clean.
Line size to the pump inlet (suction line) should not be smaller than the high pressure pump port size.
If the relief valve adjustment is part of pump, DO NOT adjust it, as it is preset at the factory. If the relief valve is separate from the pump, back off the main relief valve until the spring tension of the adjusting screw is relieved. This procedure will avoid the possibility of immediate damage to the new pump in the event that the relief valve setting has been increased beyond recommended operating pressure prior to removing the old pump.
After installation the pump must be run at the lowest RPM for 5 minutes. The pump should run free and not leak, develop heat or excess noise. Operate for 5 minutes with all valves in the open (neutral) position and then increase speed and pressure to the desired settings.
A pressure gauge should always be used at the pressure port to reset the external relief valve to its proper operating pressure.