Its task is only one: to block the metal shavings, carbon deposits, dust and other impurities in the engine oil from circulation, so that the clean oil can continue to lubricate key parts such as bearings, cams, and cylinder walls to delay wear and maintain heat dissipation.The filter element is usually folded from paper, glass fiber or stainless steel mesh, with a metal shell, and the oil inlet is connected to the main oil channel of the engine.After the vehicle starts, the oil pump pumps the oil into the filter element, impurities are trapped, and the clean oil returns to the engine.Regular replacement of the filter element is an iron rule of maintenance, otherwise the blockage of the filter element will cause the bypass valve to open, and the dirty oil will drive straight in for a long time, which is tantamount to “drinking dirty water” to the engine.Good filter≠ expensive filter, solid material selection, large number of folds, oil resistance and high temperature resistance of the sealing ring, is the last word.