When troubleshooting a hydraulic system, what should be checked first if there is insufficient pressure?

In troubleshooting a hydraulic system with insufficient pressure, checking the fluid level in the reservoir is critical because it serves as the source of hydraulic fluid for the entire system. If the fluid level is low, there may not be enough material to generate the necessary pressure or to maintain it during operation. Insufficient fluid can lead to cavitation in the pump, which not only decreases pressure but can also damage components.

While fluid temperature can influence the viscosity of the hydraulic fluid and, consequently, system pressure, it is secondary to ensuring there is an adequate supply of fluid in the system. Similarly, evaluating the condition of the pump and type of hydraulic fluid used are also important aspects of maintenance and troubleshooting but assume that there is sufficient hydraulic fluid present. Without the right amount of fluid, none of the other components can operate effectively or be assessed accurately. Thus, verifying the fluid level in the reservoir is the most immediate and vital step in addressing low pressure issues in a hydraulic system.