Is it necessary to replace the tensioner pulley when changing the car belt?
2 Answers
It is necessary to replace the tensioner pulley when changing the car belt. Here are the detailed explanations: 1. Timing belt introduction: Made of rubber, it is a consumable item that requires regular replacement. Once the timing belt ages and cracks appear, it must be replaced. Generally, it is recommended to replace the timing belt every 3-5 years or after driving about 80,000-100,000 kilometers. 2. Tensioner pulley introduction: The tensioner pulley mainly consists of a fixed housing, tension arm, wheel body, torsion spring, rolling bearing, and spring bushing. It can automatically adjust the tension according to the different tightness levels of the belt, ensuring the transmission system is stable, safe, and reliable. The tensioner pulley is a vulnerable part of car accessories. Belts can easily stretch over time. Some tensioner pulleys can automatically adjust the belt tension. Additionally, belts with tensioner pulleys run more smoothly, reduce noise, and prevent slipping. The function of the tensioner pulley also includes adjusting the tightness of the timing belt.
Last time I replaced the belt, the mechanic strongly recommended changing the tensioner pulley as well, so I asked for the detailed reason. He explained that the tensioner pulley is responsible for maintaining belt tension to prevent loosening or misalignment; if the old pulley isn't replaced and it wears out or ages on the road, it could cause the belt to slip or break. At the time, I followed his advice and replaced it to avoid potential engine trouble. Later, during a car inspection, I noticed the pulley did have slight cracks—it probably wouldn’t have lasted another six months. In short, it’s not always necessary to replace it every time, but checking its condition is crucial—especially if the car is over five years old or making unusual noises. Replacing it proactively saves money and hassle, as a failure could lead to costly towing and repairs. For non-experts, it’s best to follow professional advice and not take risks.
