What Is the Purpose of a Crankshaft Pulley?

by Andrea Stein

Car engines generate power from fuel. This power is allocated to different car components via a number of electrical and mechanical systems. A crankshaft pulley is a mechanical system that plays a key role in vehicle power distribution.

Definition

Crankshaft.

A crankshaft pulley, also called a harmonic balance wheel or crankshaft sheave, is a grooved, wheel-shaped device that connects directly to the vehicle’s crankshaft. The crankshaft essentially converts the linear, or straight, movement of pistons into a rotational motion. The crankshaft pulley typically connects to other car components via accessory belts.

Function

Car wheels.

A crankshaft pulley powers components on the crankshaft. Crankshafts are responsible for driving the car wheels. Crankshaft pulleys transmit mechanical power and torque, or the force of motion, through the pulley system to additional car elements, such as the power steering pump and alternator.

Dampener

Car rim and pulley.

Crankshaft pulleys often include an internal dampener that decreases the vibrations that run along the crankshaft pulley belts, which could potentially harm connected systems. A broken or torn crankshaft pulley belt can be individually replaced; however, a faulty dampener requires replacement of the entire crankshaft pulley.

Photo Credits

  • photo_camera Noel Hendrickson/Digital Vision/Getty Images