Wear of engine crankshaft bearings can cause abnormal noise and low oil pressure in the engine. So, what role does the bearing play in the various parts of the engine? What causes abnormal wear?
Working principle of engine bearings
Usually, the back pad of the bearing is made of steel or bronze, and the surface is coated with a friction alloy layer. It is mainly used to support the main bearing of the crankshaft and the connecting rod bearing of the connecting rod. When a high-horsepower and high-torque engine is working, a relatively high-speed sliding will form between the bearing and the crankshaft, and it will bear a huge impact load. It needs to rely on the oil film generated by the lubricating oil in the gap between the crankshaft and the bearing to lubricate and support it, and transfer the heat generated by friction to make the engine work normally.
Simply put, there needs to be a very thin oil film between the bearing and the crankshaft for lubrication, and this oil film is actually the effect of engine oil lubrication, so as to prevent hard friction between the engine crankshaft, piston and other parts. You should know that this kind of liquid lubrication friction is the most ideal working state of the bearing, which can not only cool the bearing, but also avoid dry friction caused by direct contact between the bearing and the shaft.
Although efforts are made to achieve good lubrication of bearings during design and production, the engine may be affected by factors such as vehicle usage habits, speed, working conditions, and oil quality during actual operation. The bearings may not always operate under ideal working conditions and are often in a semi-liquid or semi-dry friction state, which is never fully lubricated. Therefore, the bearing wear will be extremely serious when there is no oil.
Especially for high-horsepower and high-torque engines, once the mechanical load and thermal load are too large, the oil supply is insufficient, or the lubricating oil contains impurities or abnormal viscosity, it is difficult to form an effective lubricating oil film between the crankshaft and the bearing, resulting in dry friction between the crankshaft and the bearing.
When the bearing wear exceeds the allowable limit, it should be repaired at the service station. Otherwise, the high temperature generated by abnormal friction may melt the alloy layer on the surface of the bearing, aggravate the dry friction between the bearing and the crankshaft, and be accompanied by abnormal noise. When the engine has a burnt bearing, it will cause damage to the bearing and journal. In the worst case, the crankshaft and connecting rod will be deformed. In the worst case, the bearing will be burned and melted on the journal, causing the connecting rod to break and penetrate the cylinder block and other serious faults.
As one of the important parts inside the engine, the bearing plays a very important role during operation. If you need to purchase bearings or other engine parts in the near future, please contact us. We have been supplying engineering machinery products and related spare parts for a long time. Interested readers can click the link below to browse!
Click here to visit our spare parts web
Click here to visit our alibaba （There are more kinds of products）
Post time: Jul-25-2025