4 Common Causes of Failure in Hydraulic Gear Pumps and Troubleshooting Guide

Hydraulic gear pumps may not function as expected over time due to various factors related to working conditions and usage. This can lead to equipment slowdown or even complete stoppage of work processes. To minimize time and cost losses, considering the potential causes of malfunctions and the suggested solutions can prevent the occurrence of more significant issues.

Fault Possible Causes Solutions

The hydraulic system is not working.

 Low oil level in the tank. Add sufficient amount of oil to the tank.
Dirty filter. Clean or replace the filter.
Worn-out pump. Repair or replace the pump.
Incorrect hydraulic connections. Check the connections.

Low Pressure in the Hydraulic System.

 Pump worn-out or damaged. Repair or replace the pump.
Low power of the electric motor. Select an appropriate electric motor.
Incorrect pressure adjustment. Adjust the pressure correctly.
Oil leakage present. Check the system.
Cylinder inner surface worn-out. Inspect and rectify the issue if necessary.
Low oil viscosity. Use oil with the appropriate viscosity.
There is air in the oil. Empty the system and use non-foaming oil.
Air in the system.
a) Pump is slow during initial start-up and speeds up as the oil gets warmer.
b) Pump is fast during initial start-up and slows down as the oil gets warmer.
 Remove air from the system.

a) Oil is too thick, add oil with the appropriate viscosity.

b) Oil is too thin, add oil with the appropriate viscosity.

Hydraulic Oil Overheats.

 Cavitation problem exists. Check for air in the system.
Insufficient oil. Add sufficient amount of oil to the tank.
Dirty oil. Use clean oil.
Worn-out pump. Replace worn-out parts or the pump.
High pressure. Check the pressure setting.
Hoses or valves in the system are too small. Replace with proper-sized ones.
Compression and excessive bends in the lines. Ensure oil lines are properly aligned and free-flowing.

Excessive Noise in the Hydraulic System.

 Insufficient amount of oil. Fill with enough oil.
Oil is too thick. Empty the oil and refill with the correct type.
Dirty filter. Clean or replace the filter.
Narrow suction line. Expand the suction line.
Clogged suction line. Clean the suction line.
Vent cap on the hydraulic tank is clogged. Clean or replace the filter.
Oil foaming. Empty the system and use non-foaming oil.
Small filter. Use a larger filter.
Coupling is misaligned. Align the coupling between the pump and drive shaft.
Pump is drawing air from the shaft or suction pipe. Apply oil to suspected areas, listen to the pump's sound, and tighten any leaking spots.
Pump running at excessive speed. Check the pump's maximum speed, reduce the speed, or select a larger pump.