When the engine is running, because the working conditions of the moving parts of the engine are different, the required lubrication strength is also different, so different lubrication methods should be adopted accordingly. Generally speaking, there are four kinds of lubrication methods used in an engine.

　　①壓力潤滑：壓力潤滑是利用機油的壓力將油輸送到各摩擦表面進行強制性潤滑，如曲軸主軸承、連桿軸承及凸輪軸軸承等處，需要以一定壓力將機油輸送到摩擦面的間隙中。

　　Pressure lubrication: Pressure lubrication is the use of oil pressure to transport oil to the friction surface for compulsory lubrication, such as crankshaft main bearings, connecting rod bearings and camshaft bearings, need to be a certain pressure to transport oil to the friction surface clearance.

　　②飛濺潤滑：利用曲軸的運轉將油從軸承兩側甩出，在曲軸箱內形成許多油滴或油霧，飛濺到各摩擦表面進行潤滑，如氣缸壁、活塞銷等。

　　Splash lubrication: oil is thrown out from both sides of the bearing by crankshaft operation, and many oil droplets or mists are formed in the crankshaft box, splashing onto the friction surfaces for lubrication, such as cylinder wall, piston pin, etc.

　　③綜合潤滑（壓力和飛濺結合）：這種方法廣泛應用到現代汽車發動機上。

　　(3) Comprehensive lubrication (combination of pressure and spatter): This method is widely used in modern automotive engines.

　　④潤滑脂潤滑：發動機的附件如發電機、水泵等軸承均采用潤滑脂潤滑，需要定期加注或清洗更換。

　　(4) Grease lubrication: Engine accessories such as generators, water pumps and other bearings are lubricated with grease, which needs regular filling or cleaning and replacement.