Hydraulics in the heat: how to protect against system overheating?
2025. June 25.Hydraulic systems are particularly vulnerable to overheating in the summer heat, which not only reduces efficiency but can also cause serious damage to machinery. In the following article, we explain how to protect against overheating caused by the heat and how to keep your systems running optimally.
How does heat affect hydraulic systems?
High ambient temperatures have a significant impact on the operation of hydraulic systems. Overheating hydraulic oil reduces its viscosity, which reduces lubricity and increases wear. In addition, overheating can accelerate the oxidation of the oil, which can lead to deposits and contamination, further degrading system performance and lifetime.
The role of proper cooling
Temperature control is key to the efficient operation of hydraulic systems. However, heat exchangers and oil coolers can help remove excess heat from oil, maintaining its optimum viscosity and extending component life. There are two main types, air-cooled oil coolers and water- and liquid-cooled heat exchangers. The former use fans to cool the oil, making them ideal for mobile equipment and in places where there is no water source. The latter, on the other hand, has a high cooling capacity and is less sensitive to changes in ambient temperature.
Regular maintenance is the key
Regular care and monitoring is essential to avoid overheating. For example, checking the level and condition of hydraulic oil, changing filters and inspecting seals and hoses are important factors. Heat can accelerate the wear of seals and hoses, which can lead to leaks and system failures. Keeping the system clean is also very important, as dust and dirt impair heat transfer and promote overheating.
Innovative solutions against the heat
Technological advances offer new possibilities for heat management. Adaptive heat exchangers, for example, can be mounted directly on hydraulic tubes, increasing the heat dissipation surface and improving cooling without the need for major modifications. In addition, two-phase cooling technologies that exploit liquid-vapour phase change can significantly increase cooling efficiency by up to seven times compared to conventional methods.
Summer challenges for agricultural machinery
During the summer harvesting seasons, agricultural machinery such as tractors, combine harvesters, loaders, sprayers and balers operate for hours a day in extreme conditions, if they can. The dusty environment, heavy loads and constant exposure to the sun mean that these machines are subject to considerable heat stress. This is particularly true of the hydraulic systems, which play a key role in the operation of most moving machine parts (hoists, rollers, steering systems, etc.).
Overheating of hydraulic oil not only reduces the efficiency of machinery, but can also lead to serious problems that can cause downtime and significant losses for the farmer, especially if this occurs during peak harvesting season.
Technological solutions
Digital technology has already arrived in agricultural hydraulics. Smart sensors can now indicate temperature changes in real time and compare them with other operating parameters such as pressure or oil flow. On-board systems linked to the sensors send a warning to the tractor or combine operator if overheating is imminent, so he can intervene in time, for example by stopping the machine or reducing the load.
Some more advanced systems, such as those on John Deere or Fendt tractors, now use predictive maintenance tools. These can predict failure risks, such as when to expect a sustained rise in temperature or when an oil change is needed.
The summer heat is therefore a major challenge for hydraulic systems, but with proper maintenance, cooling solutions and innovative technologies, overheating can be prevented. Regular checks, proper cooling systems and the integration of new technologies will ensure that systems operate reliably and efficiently even in the hottest months.