1. The movement of the shock absorber is adhered to by sand. During the reciprocating movement of the shock absorber, the sand core moves randomly and scratches the oil seal, causing the sealing performance of the oil seal to fail, and the damping oil seeps out from the oil seal.
2. After the shock absorber is subjected to an abnormal impact, the shock absorber core is bent and deformed, causing a matching gap in the oil seal. This will also invalidate the sealing performance of the oil seal. This type of situation mainly occurs in McPherson shock absorbers that are often subjected to forces that are not axially balanced with the shock absorber.
3. Due to incorrect installation and adjustment. The shock absorber is completely stretched during use, so that the piston reaches the top, and the impact self-lubricating bearing is deformed, which causes the oil seal to be damaged and oil leakage.
4. The quality of the oil seal used by the manufacturer when manufacturing the shock absorber is not good enough.
5. The flatness of the coating of the shock-absorbing movement is not good. After being pressured by the shock-absorbing oil, the oil leaks from the fine fitting gap.