Which of the following is true regarding the operation of hydraulic pumps?

The operation of hydraulic pumps is highly dependent on proper maintenance to ensure their efficiency and longevity. Regular maintenance checks are necessary to keep the hydraulic fluid at the appropriate level, check for leaks, monitor the condition of seals, and ensure that filters are clean. Neglecting these aspects can lead to decreased performance, potential breakdowns, or even catastrophic failures.

Understanding this principle is essential for linemen and those working with hydraulic systems, as it emphasizes the importance of routine inspections and maintenance practices. By maintaining hydraulic pumps, you can ensure optimal performance, enhance safety, and extend the life of the equipment, which is crucial for any lineman apprentice to grasp.

The other options do not accurately reflect the operational capabilities of hydraulic pumps. For instance, running without fluid would lead to damage, electric power is not the only means of powering hydraulic pumps (as they can also be driven by mechanical means), and temperature can significantly influence the viscosity of hydraulic fluids, thus affecting pump performance.