The idler pulley is a common part that’s found on the majority of the vehicles on the road. Its primary function is to provide tension and guide the engine drive belt. These belts wrap around the various parts of the engine such as the power steering pump, alternator, water pump etc... To keep it simple, idlers are complementary pulleys that make the entire system run smoothly.
So, what are some signs of a worn idler pulley? First, let’s start with visual cues. Like many automotive parts, the idler pulley becomes worn over time. The pulley spins against the belt wearing down both parts. This wear reduces tension which can lead to belt slippage. Even more noticeable is a cracked or damaged pulley or bearing. This damage interferes with the rotation of the belt causing torn belts, or the belt falling off of the engine. Without a belt, stalling and overheating of the engine become commonplace. For auditory cues, squealing noise from the engine belt can be a tell-tale sign. As the pulley wears, the engine belt may squeal as it rubs against the surface of the pulley. The issue will worsen with time.
Generally, idler pulleys will eventually require a replacement. All engine pulleys are extremely important to the function of your engine and replacing them is no small task. If you have any of these issues, bring your vehicle to an ASE certified auto shop such as Ferber’s Tire and Auto for an inspection.