Finding the source of failure in a hydraulic system can at times be a challenge. There are multiple potential sources of the problem from pumps, fluids, motor, or valves. The issues could also be due to poor maintenance or user error.

Below is a list of the top reasons for the failings of hydraulic systems.

Air and Water Contamination

Air and water contamination make up about 80 to 90% of all hydraulic system failures and is the reason we put it at the top of this article. Air contamination is caused by the entrance of air into the closed hydraulic system. These air breaches cause significant damage to the pump and other hydraulic components over time.

Warning signs of air contamination is generally a knocking sound coming from the pump. Whereas the cavitation caused by these issues can make a whining noise, cavitation causes dissolved air to pull out and implode, causing significant wear and damage to pumps.

Fluid Levels and Fluid Quality

Fluid levels as well as fluid quality can negatively affect your hydraulic systems as well. Using the correct fluids for your system is crucial, with some oils and fluids made to specifically counter foaming due to air leaks and other contaminants as mentioned earlier. Low fluid levels allow for air cavitation and cause premature and serious wear on your hydraulic system.

Temperature Issues

Fluid Viscosity is a critical component in maintaining a healthy and functioning hydraulic system. Viscosity depends on factors like temperature and pressure. If either the temperature or pressure is not within recommended guidelines your pumps will experience unnecessary strain that will eventually lead to damage and failure.

As a basic guideline the temperatures of 180 degrees Fahrenheit or higher will have negative effects on your equipment and are usually reached if cooling of the system is not working properly. On the other end, having hydraulic fluids to cool can also be detrimental. Putting hydraulic systems under heavy loads before the temperatures reach 70 degrees can cause cavitation due to thicker oil viscosity, hampering the oil from flowing smoothly throughout the system.

User Errors

User error can also be a major contributor to hydraulic system failure. These issues can be due to faulty installations of things such as hydraulic lines and fittings, causing leaks and allowing air or contaminants to enter the system. Other issues could be installation mistakes such as improper shaft installation with the shaft spinning in the wrong direction, causing negative pressure throughout the system, or the use of the wrong parts allowing for failures to occur.

Poor Maintenance

Not keeping up on the maintenance of your hydraulic systems can also have seriously detrimental effects in terms of failure and the machines lifespan, causing it to fail far before the end of the systems estimated lifespan. Checklists should be put in place as well as daily and monthly inspections to ensure that fluid levels are at proper levels and that the fluid is not contaminated in any way.

Inspection of components and filters should be done and signed off, as well as draining and replacing the oil on a set schedule as well as keeping records of every inspection, and fluid change that takes place, or any work, repairs and maintenance that has taken place. Doing this will ensure that you get optimum performance as well as the most out of your equipment’s lifespan, with proper maintenance helping many hydraulic systems exceed normal life expectancy.


The bottom line to prevent the failure of your hydraulic systems is maintenance and seeing the warning signs and fixing the issues before it becomes too late. Proper maintenance and record keeping ensuring that it was performed is by and large the best way to prevent all hydraulic system failure.

If your hydraulic equipment has failed or needs a reliability centered maintenance check, Servo Kinetics can help. We are a full-service hydraulic repair, inspection and rebuild facility that delivers the highest quality standards at the lowest possible cost with a fast turnaround. Our hydraulic repair services include Vickers classic factory rebuilds, Beach Russ repair, EHC energy pump repair services and much more.

We have been in business for over 45 years working with industries that have very exacting standards which include some of the most tech savvy companies in the world. Call us to learn more about our services and ask about our Special Offers!