Under what circumstances should the four supporting parts of a car be replaced?

[OLaura]

Car four supporting parts should be replaced under the following circumstances: Engine overload: The higher the engine speed and the greater the load, the more mixed gas will enter the crankcase, which can easily cause the oil-gas separator to overload and fail. Excessive clearance: The valve guide and valve clearance in the cylinder head are too large (especially when using butterfly valve braking at this time). Air compressor blow-by: Air compressor blow-by is caused by wear of the air compressor piston rings, which leads to obstruction of the air compressor's exhaust and results in blow-by. For example, blockage of the air compressor's air outlet pipe or drying tank blockage. As the vehicle ages, the clearance values of various parts will also increase, making the probability of such situations more likely to occur.