What is the function of the piston in the power package reservoir?

The function of the piston in the power package reservoir is to protect the engine-driven pump. This role is critical because the piston helps to manage fluid levels within the reservoir, ensuring a consistent supply of hydraulic fluid to the pump. By doing so, it prevents cavitation, which can occur when the pump does not receive enough fluid, potentially causing damage to the pump components. Therefore, the piston acts as a safeguard, maintaining optimal fluid conditions that preserve the functionality and longevity of the engine-driven pump.