How to judge whether the shock absorber spring is damaged

Absorber is used to suppress the vibration generated by the rebound of the spring after shock absorption and road impact, accelerate the vibration attenuation between the frame and the car body, and improve the driving stability of the car. When passing on an uneven road, although the shock-absorbing spring can filter the vibration of the road, the spring itself will also have reciprocating motion. The function of the shock absorber is to inhibit the bounce of this spring.

As an important part of the automobile suspension system, the automobile shock absorber has a great influence on the driving comfort. What we usually call the shock absorber is a component, which consists of the shock absorber core, spring, and top cover. Composed of several basic components such as cushion rubber and dust cover, high-end automobile shock absorbers are more complicated, and they also include smart sensors, electric pumps, and computers.

Shock absorber damage usually has some signs, such as sinking or tilting of the vehicle chassis, creaking noises on bumpy roads, and electronic warning lights on high-end cars.

As a mechanical part, after the shock absorber is damaged, some small parts on the assembly can be replaced by decomposition and replacement to reduce the cost. The most expensive is the damping core. Once leakage or deformation occurs, it must be replaced.

If oil leakage occurs in the shock absorber of a car, it is undoubtedly very dangerous for the shock absorber. Then, once a leak is discovered, prompt remedial measures will be taken. The main inspection items are oil seal washer, oil seal washer rupture and damage, oil storage cylinder cover, check whether these parts have loose nuts.

If oil leakage is found, first tighten the cylinder head nut. If the shock absorber still leaks, the oil seal may be damaged and the seal ring has failed. Replace with a new seal ring. If the oil leakage still cannot be eliminated, pull out the damping rod. If it feels that there is a pinch or the weight is different, 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 whether the piston Whether there are scratches or pull marks on the surface of the connecting rod and the cylinder.

If there is no oil leakage, check the shock absorber connecting pins, connecting rods, connecting holes, rubber sleeves, etc. for damage, desoldering, breaking or falling off. If the above inspection is normal, the shock absorber should be further disassembled to check whether the matching gap between the piston and the cylinder is too large, whether the cylinder is strained, whether the valve is well sealed, whether the valve disc and the valve seat are tightly joined, and reduce Whether the telescopic spring of the vibrator is too soft or broken, and repair it according to the situation by grinding or replacing it.

In addition, the shock absorber will also produce noise failures in actual use. This is mainly due to the collision of the shock absorber with the leaf spring, the frame or the axle, the damage or fall of the rubber pad, the deformation of the shock absorber dust tube, and the lack of oil. If the cause is caused, it is necessary to find out the cause and carry out maintenance.

When driving on uneven roads, please pay attention to the four corners of the vehicle. If the shock absorber is damaged, abnormal noises will be produced. You will hear the car continuously rumbling sound somewhere in the four corners. If you cannot determine the location of the sound for a while, you can find another partner, let him sit in the back, judge whether the sound is from the front or the back, and then judge. If you can hear an obvious and constant humming sound, it is probably caused by damage to the shock absorber.

Another damage form of damping is leakage, because there is an oil seal at the upper end of the damping, if the oil seal is damaged, the internal hydraulic oil will leak directly. In this way, you need to pick up the upper shelf of the car, and then look at the four shock absorbers to see if there is any oil leakage. If there is oil leakage, it is easy to find.

Try to replace the shock absorbers in a pair, that is, if one of the front wheels is damaged, it is recommended to replace the shock absorbers of at least two front wheels together, so as to ensure that the new shock absorber is replaced. , Both sides can work in the same state.

After inspection and repair, the shock absorber should be tested for performance on a special test bench. When the resistance frequency is 100±1 mm, its extension resistance and compression resistance should meet the requirements. The maximum resistance of the stroke is 392~588 N, the maximum resistance of Dongfeng Motor's extension stroke is 2450~3038 N, and the stroke compression is 490~686 N. If there are no test conditions, iron bars can also be used to penetrate into the lower ring of the shock absorber, step on both ends of the ring with two feet, hold the upper ring with both hands and pull it back and forth for 2~4 times. When pulling up, the resistance is large, and pulling down Does not feel laborious, and the pulling force is restored compared to before maintenance, and there is no sense of empty travel, indicating that the shock absorber is basically normal