KICK@$$ Every. Single. Day.


6 Common Causes of Hydraulics Overheating

Downtime is money lost, don’t let these conditions bear you down.

Overheating is a frequent problem within hydraulic systems that may be determined by specific components. This internal problem lies within the pump and causes a hydraulic system to overheat in the following ways: 

Contaminated Hydraulic Fluid

Contaminated hydraulic fluid is a common cause for a Hydraulic system to overheat. This can occur when the container is not sealed properly which causes dust, dirt, debris, or moisture to contaminate the fluid. With hydraulic systems running at higher pressures and more efficiently than ever before, it is important to monitor the cleanliness of one’s hydraulic fluid. Reducing contamination can decrease damage and will allow one to get the most out of their equipment.  

Wrong Valve Calibration

Wrong valve calibration could result in pressure difficulties which can cause a hydraulic system to overheat. The main cause of this is when a facility’s plant design changes and maintenance recalibrate the pressure relief valves for the updated operating pressure. If maintenance adjusts the pressure, and it still does not solve the problem, the pressure relief valve may have to be replaced entirely. Erosion to a valve is a common occurrence as dirt and debris settle and collect throughout time. Maintaining the correct pressure will help your system keep up with production and not slow down.  


Aeration in a hydraulic system can be a common issue and is caused by an outside air leak in the suction line. The pressure used in the suction line of hydraulic systems is below atmospheric pressure, so oil cannot leak out, but air can leak in. This will occur when there are loose, leaky seals and fittings which will allow the air to seep in. Aeration can have several negative effects on top of overheating such as increased pump cavitation, excessive noise, and loss of horsepower. Some symptoms of Aeration may include foaming of the fluid, irregular movements, and banging and or loud clicking noises as the hydraulic system compresses and decompresses.  

Blocked Heat Exchanger

A blocked heat exchanger is significant to heating one’s hydraulic system, while cooling it down is just as important. An infrared thermometer is an effective way to check the temperature of a heat exchanger. The adjustments can be made according to the design of the flow rate of oil. Make sure to replace the fluid fitters located in the pump on a regular basis to ensure they will not get blocked and overheat.  

Oil Type

Oil Type plays a critical role in any hydraulic system. The wrong oil will not only affect the performance of the system but also cut down the lifespan of the machine. The oil Viscosity determines the maximum and minimum temperatures in which a hydraulic system can safely operate. Thin oils have a low viscosity and flow more easily at low temperatures than thicker oils that have a higher viscosity. If the oil is too thin it can cause internal friction which creates heat and can cause the system to overheat 

Low Reservoir Fluid

Low reservoir fluid is a common cause of overheating in hydraulic systems as it releases built-up heat from the machine into the fluid. Not having enough reservoir fluid can contribute to cavitation and ultimate damage to the pump. 

Hydraulic pump failure can damage the entire hydraulic system. When a pump fails, debris, dirt, and grime kick out downstream and can affect the oil, filter, valves, fluid, and actuator. Contact our sister brand, Allied Hydraulic, for help with hydraulic component repair.

Check out Allied Hydraulic’s new video series, where they dive into the most common reasons your hydraulic components might be failing.


We’re looking forward to helping you. Whether you have questions about products, services, or a demo, our team is ready to help.

Fields with an asterisk* are required. This information allows us to better assist you. 

We promise not to spam you and will only be sending information worth your valuable time.

Your information will not be shared beyond our organization. The information collected is simply used to better assist you. Please visit our Privacy Policy to learn more.