What Does Engine Cylinder Scoring and Bearing Burning Mean?

[LucyLynn]

Engine cylinder scoring refers to vertical scratch marks appearing on the cylinder walls of an engine; engine bearing burning means severe scratches and abrasions on the journal surface, which oxidize and turn blue. Below are some related expanded contents: Causes of engine cylinder scoring: Cylinder scoring is related to engine lubrication. If the engine lacks oil, the oil has been used for too long and its viscosity is insufficient, the oil passages are blocked, or there are too many impurities in the oil, all these can cause cylinder scoring. Causes of engine bearing burning: Bearing burning is mainly caused by insufficient lubrication or too small a gap between the journal and the bearing. When a sliding bearing is working, a very thin oil film is required between the bearing and the rotating shaft for lubrication. If lubrication is poor, direct friction occurs between the bearing and the rotating shaft, generating very high temperatures. Although bearings are made of special high-temperature-resistant alloy materials, the high temperatures produced by direct friction are still sufficient to burn them out.