For a hydraulic fluid to function properly over acceptable periods of time, it must?

For a hydraulic fluid to function properly over acceptable periods of time, it is essential for the fluid to be kept clean. Cleanliness in hydraulic fluids is crucial because contaminants such as dirt, rust, and other particles can interfere with the fluid's ability to lubricate, transmit pressure, and function effectively. Contaminants can lead to wear on components, cause blockages in lines, and ultimately result in system failures.

Maintaining the cleanliness of hydraulic fluid helps ensure optimal performance, longevity of the system, and reliable operation under various conditions. Regular filtration and monitoring are typically employed to maintain the purity of hydraulic fluids, making cleanliness a key factor in their effectiveness and reliability in hydraulic systems.