1. The car shock absorber is usually connected to the car body and chassis. Loosen the upper and lower screws and pry out with a large screwdriver. When replacing a new one, touch a little bit of butter. Sometimes the upper and lower positions may not be right. If the upper and lower gap is large, hang the shock absorber first. Just pull one end of the device and the other end to the correct position; if the gap is small, just find a jack to hit the car body to the correct position and tighten the screws.
2. Failure repair
After determining that the shock absorber is faulty or invalid, first check whether the shock absorber is leaking or has traces of old oil leakage. The oil seal washer and sealing washer are broken and damaged, and the oil storage cylinder head nut is loose. It may be that the oil seal and sealing gasket are damaged and invalid. Replace with new seals. If the oil leakage still cannot be eliminated, pull out the shock absorber. If you feel a hairpin or change in weight, check whether the gap between the piston and the cylinder is too large, whether the piston connecting rod of the shock absorber is bent, and the piston connecting rod Whether there are scratches or pull marks on the surface and cylinder. If the shock absorber does not leak oil, check the shock absorber connecting pin, connecting rod, connecting hole, rubber bushing, etc. for damage, desoldering, cracking or falling off. If the above inspection is normal, the shock absorber should be further disassembled to check whether the matching clearance between the piston and the cylinder is too large, whether the cylinder is strained, whether the valve seal is good, whether the valve clack and the valve seat are tightly fitted, and whether Whether the extension spring of the shock is too soft or broken, it should be repaired by grinding or replacing parts according to the situation.
3. In addition, the shock absorber will have a noise failure in actual use, which is mainly due to the shock absorber colliding with the leaf spring, the frame or the axle, the rubber pad is damaged or falling off, and the shock absorber dust tube is deformed. If it is caused by insufficient oil, the cause should be found out and repaired. After the shock absorber is inspected and repaired, the performance test should be carried out on a special test bench. When the resistance frequency is 100±1mm, the resistance of the extension stroke and compression stroke should meet the requirements. For example, the maximum resistance of Jiefang CA1091's extension stroke is 2156~2646N, the maximum resistance of compression stroke is 392~588N; the maximum resistance of Dongfeng Motor's extension stroke is 2450~3038N, and the maximum resistance of compression stroke is 490~686N. If there is no test condition, we can also adopt an empirical method, which is to use an iron rod to penetrate into the lower end of the shock absorber ring, step on both ends of the shock absorber with both feet, hold the upper ring with both hands and pull it back and forth 2~4 times. The resistance is great when you pull up, and you don’t feel any effort when you press it down, and the resistance of stretching is restored compared to before repair, and there is no sense of air travel, indicating that the shock absorber is basically normal