What does an idler pulley do on a car?
An idler pulley is a specific part of a vehicle’s belt system that helps regulate how the belts run from the crankshaft to generate movement in other parts and engine accessories. It is one of a set of pulleys that a belt rests on.
What’s the difference between a flat belt and idler pulley?
As the name implies, a flat belt is one that has a relatively flat surface on the entire length of the belt. The pulley prevents this belt from ever slipping out of its position. The idler pulley may have a smooth outer wall, but the edges typically have retainers while some may have a middle groove to keep the drive belt in place.
What happens to the idler belt when the car is running?
If you look at the belt when the car is running at idle, it moves quite smoothly along the system. When there is significant deterioration of pulley hardware, the belt moves from side to side.
How can I fix a broken idler pulley?
Check the alignment by holding a straight-edged ruler across the pulleys or using a laser alignment tool. To change a broken pulley, first remove the attached belt. While holding the pulley, remove the center bolt using a 13-millimeter socket wrench. Replace the pulley, and retighten the bolt. The torque should be 18 feet per pound.
What does the idler pulley actually do?
The idler pulley is one pulley in a set that drives the belt system of a vehicle. The idler pulley regulates the belts that connect to the crankshaft and are used to produce movement in numerous engine accessories, such as the alternator, steering pump and air-conditioner compressor.
How do I replace idler pulley?
How to Replace the Idler Pulley on a Ford Focus. Raise the hood and locate the belt tensioner. The tensioner is an arm with a pulley at the end of it which holds tension on the serpentine belt. Slip the belt tensioner tool into the tensioner and pull the tool to the side, releasing the tension from the belt.
How much does an idler pulley replacement cost?
At AutoZone, for instance, a complete kit, including the idler pulley, can cost $75 to $130 , but the idler pulley on its own will cost $17 to $35+. The best sellers on Amazon retail for about $15 to $35.
How does belt pulleys work?
How pulleys work. When one of the accessory pulleys rotates due to drive belt motion , it causes the accessory to activate. For instance, the movement of the alternator pulley causes a magnetic field to form, which is then converted to electricity, causing the alternator to work.