What Are the Causes of Belt Noise During Cold Start?
2 Answers
The causes of belt noise during cold start are: 1. The belt tightens due to low temperature before the vehicle is ignited, resulting in noise; 2. Severe aging of the belt, approaching the end of its service life; 3. The belt is either too loose or too tight. The functions of the belt are: 1. Ensuring the accuracy of intake and exhaust timing; 2. Ensuring the synchronization of engine ignition and cylinder movement; 3. Ensuring smooth power output from the engine. The method for replacing the vehicle belt is: 1. Lift the vehicle and remove the right front wheel fender liner; 2. Remove the generator belt and the generator belt tensioner; 3. Loosen the crankshaft pulley screw; 4. Open the engine hood and remove the water reservoir; 5. Remove the engine mounting bracket and the protective cover on the belt; 6. Unscrew the generator fixing screw and remove the generator; 7. Remove the cylinder block mounting bracket and take off the crankshaft pulley; 8. Rotate the crankshaft to the top dead center position of the cylinder and mark it; 9. Remove the belt and the tensioner.
My old car also had this issue, making annoying squeaking noises when starting in cold weather. The main reason is that rubber hardens in cold temperatures, especially in the morning when starting, causing insufficient friction between the belt and the steel pulley, just like how plastic becomes brittle in winter. Another issue is belt aging—after seven or eight years of driving, the edges of the belt can crack, and the uneven contact surface makes it prone to slipping and producing high-pitched squeals. Also, don’t forget to check the belt tensioner pulley; the spring weakens over time, leading to a loose belt and constant noise. Last winter, I replaced the belt and had the mechanic adjust the tensioner pulley. It hasn’t made a sound since then—over half a year now.
