Why Does the Car Timing Belt Skip Teeth?
4 Answers
The reason for the car timing belt skipping teeth is that it has become loose, and it can be fixed by tightening it at a repair shop. The timing belt is a crucial component of the engine's valve timing system, ensuring accurate intake and exhaust timing by connecting to the crankshaft and maintaining a specific gear ratio. The use of a belt instead of gears for transmission is due to the belt's lower noise, minimal self-variation, and ease of compensation. The timing belt plays a connecting role—linking the upper part to the timing pulley on the engine cylinder head and the lower part to the crankshaft timing pulley. The timing pulley is connected to the camshaft, which has cams that contact small rocker arms. The rocker arms generate pressure through the power transmitted by the timing belt, performing a lifting function.
As a mechanic with years of experience, I must say timing belt tooth skipping is a common issue. The main cause is belt aging—after tens of thousands of kilometers, the material becomes brittle and loose, unable to withstand engine operation. Tensioner problems are another culprit; if it fails, the belt goes slack and skips teeth with movement. Don’t overlook external contamination, like oil leaks coating the belt, making the surface slippery and prone to skipping. Improper installation is also a pitfall—misaligned teeth during installation lead to misalignment under load. The consequences are severe: timing disruption causes valves and pistons to collide, destroying the engine. I recommend checking the belt every 60,000 km—don’t cut corners on safety. Regular maintenance saves a lot of trouble.
My old car had a timing belt skip teeth last year, and the engine made terrifying creaking noises. Upon inspection, the cause was neglect in maintenance—the belt had cracked after exceeding 100,000 km without replacement, coupled with loose tensioner bolts that caused skipping under high-speed vibrations. Oil contamination was also a factor; unrepaired oil leaks from the chassis made the belt slip. This issue cost me dearly—over 10,000 yuan in engine repairs—a painful lesson. Typically, there are no warning signs before skipping occurs, so make it a habit to replace the belt every 5 years or 80,000 km (refer to the manual). Don’t wait until the car breaks down to regret it. Routine checks for belt tension can prevent disasters. I’ve learned the importance of regular maintenance—letting small issues escalate isn’t worth it.
Having driven an old car for decades, I've personally experienced timing belt skipping teeth. It mostly happens due to neglected inspections – when the belt gets old and loses tension, it's prone to slipping and skipping. Oil leaks contaminating the belt surface are also common, as oil stains prevent it from gripping the gears properly. Careless installation or poor-quality belts can also cause skipping. This is a serious failure – once the timing belt skips, the engine's timing goes haywire, potentially damaging the cylinder block directly, leading to costly repairs. I recommend all car owners replace the belt according to the manual's schedule and not delay minor maintenance. Pay attention to any abnormal engine noises yourself – addressing issues early ensures safety and peace of mind.
