The non-standard bearing of the automobile tightening wheel is a key component in the tightening wheel system. It is responsible for adjusting the tension of the transmission belt and ensuring the normal operation of engine accessories (such as generators, air conditioning compressors, etc.). Since the size, material or performance of non-standard bearings differ from that of standard bearings, their operation and maintenance need to be more refined. The following are the detailed operating steps and precautions: 1. Operation steps 1. Prepare tools and materials before installation: bearing puller, press, torque wrench (accuracy ±5%), dial table. Auxiliary materials: high-temperature grease (such as lithium-based grease, temperature resistance ≥120℃), detergent (such as carburetor cleaning agent), sealant (such as silicone sealant). Protective equipment: gloves, goggles, dust masks. Bearings and components inspection Bearing inspection: Appearance: No cracks, rust, peeling; the surface of the raceway and rolling elements is smooth, without pitting or scratches. Dimensions: Use a micrometer to measure the inner diameter, outer diameter and width, and match with the tightening wheel shaft and housing