In most automotive applications, what drives the water pump?

• A. Camshaft
• B. Crankshaft
• C. Timing belt
• D. Water pressure

Answer: (B)

The water pump is driven by the engine’s rotating drive system, typically tied to the crankshaft. The crankshaft is the main source of rotational energy in an engine, and it passes that motion to accessories—such as the water pump—through belts or direct pulleys. The camshaft controls valve timing, not the water pump, so it’s not the driver. In many designs the belt that links the crankshaft to the pump (serpentine or timing belt) transfers that motion, but the origin of that drive is the crankshaft. Water pressure is what the pump generates, not what drives the pump. So the crankshaft is the correct driver.