What Causes Abnormal Noise in Car Engine Belts?
2 Answers
Introduction to the causes of abnormal noise in car engine belts is as follows: 1. Long squealing or screeching noise: This is usually due to improper installation of auxiliary devices or poor quality of original equipment. In this case, check the relevant components that may cause the fault, and inspect whether there is dirt on the surface of all pulley wheels. 2. Hissing, rattling, roaring, or humming noise: Continuous hissing or rattling noise that increases with engine speed usually indicates a lack of lubrication in the bearings of the auxiliary rotating mechanism. Using a stethoscope can help further identify these noises. Then remove the drive belt, manually rotate the suspected faulty components, and replace the bearings or the corresponding parts.
Recently, my car's engine belt has been squeaking, and I've been thinking about various possibilities. The main reasons are belt aging or slackness—after several years of use, the belt naturally wears out and hardens, causing noise. Dirt or oil contamination on the belt can also lead to strange noises, especially if the driving environment is usually dirty. A loose or faulty tensioner needs attention, as it can fail to press the belt tightly, causing it to slip and screech. In some cases, misaligned or worn pulleys increase friction and start 'singing.' Last time I went to the repair shop, the mechanic said belts should be checked every 60,000 kilometers for wear and tear, and replacing a new belt isn't costly. The noise isn't just annoying—if the belt snaps, it can stop the car abruptly and even damage engine components, leading to expensive repairs. It's best to address the issue as soon as you hear any noise rather than pushing through.
