Common Hydraulic Failure Causes
Most often, failures start with hydraulic pumps. Studies show that 90-95% of hydraulic failures are caused by an increased rate of wear and tear on the pump due to:
- Fluid contamination caused by foreign material in the hydraulic fluid.
- Aeration and cavitation caused by improper design.
- Restricted fluid flow to pump
- Loose connection or fittings on suction line
- Low hydraulic fluid level and/or low NPSHA
- Excessive pump speed; be sure to check specifications of the pump and motor
- Incorrect hydraulic fluid or wrong oil viscosity
- Foaming oil and/or low or old oil levels
- Clogged reservoir air breather vent
- Too low of an oil temperature
- Damaged or worn pump
- Over-pressurization: subjecting a pump to pressures higher than its design specs call for.
- Poor fluid viscosity: higher than required viscosity leads to cavitation; lower than required results in too much heat and leaks in the pump.
- Excessive heat: heat can be either a byproduct of other failures or a trigger. It is always a warning sign that requires immediate attention.