Most hydraulic motors are modified designs of ______.

• A. Pumps
• B. Valves
• C. Filters
• D. Cylinders

Answer: (A)

Hydraulic motors are built from pump concepts because both devices handle the same hydraulic energy and use similar internal components, but in opposite roles. A pump converts mechanical energy into fluid pressure and flow, while a motor converts that fluid pressure into mechanical rotation and torque. To make a motor, the pump’s geometry (such as gears, pistons, or vanes) is reused and modified so the pressurized fluid acts to drive rotation rather than create flow. This is why most hydraulic motors are modified designs of pumps.

Valves control flow and direction, not energy conversion; filters remove contaminants, and cylinders provide linear motion. The defining reason the pump-based approach fits hydraulic motors so well is the direct use of fluid energy to produce rotational motion.