18.9. Check of the shock-absorber
The characteristic signs testifying to malfunction of the shock-absorber are:
– long rocking of a body at the movement on an uneven paving;
– the increasing fluctuation of a body at the movement on an uneven paving;
– the non-uniform and unstable motion of wheels (jumping) at the movement in the certain range of speeds, including on turns;
– a deviation from the set trajectory of the movement of the car when braking;
– unstable passing of turns and drift of the car;
– the increased wear of tires which is characterized by deleting of their drawing;
– emergence of clicks and extraneous noise at the movement of the car. Clicks and easy blows can be caused also by other malfunctions of a suspension bracket, in particular, weakening of threaded connections, failure of bearings of naves or wear of hinges of equal angular speeds of shaft of the drive.
For check of technical condition of the shock-absorber remove it from the car.
Examine the case and a rod of the shock-absorber. On the case there should not be mechanical damages, on a rod – corrosion traces. Install the shock-absorber in vertical position and check its work, moving a shock-absorber rod at all length of the course both up and down at the length of 50 - 100 mm. In all cases the rod of the shock-absorber has to move smoothly, with a notable resistance. If the rod moves breakthroughs or is damaged, the shock-absorber is subject to replacement.
The rod of the gas-filled shock-absorber can spontaneously move forward from the shock-absorber. Lack of spontaneous promotion of a rod from the shock-absorber, does not testify to malfunction. In this case the operating mode of the gas-filled shock-absorber corresponds to an operating mode of the hydraulic shock-absorber. The shock-absorber performs the functions and in the absence of the excessive pressure of gas, but at the same time additional noise when moving the piston can appear.
Check lack of leak of damping liquid. Small dribble of oil at preservation of normal operability of the shock-absorber is allowed. If the spot of the liquid which flowed out from the shock-absorber extends only to the lower support of a spring, then it is considered the normal phenomenon. At insignificant dribble of liquid from the shock-absorber the sealing ring of a rod of the shock-absorber is greased that increases the term of its service.
In the presence of strong leak of liquid the shock-absorber needs to be replaced.
Fig. 12-22. Back rotary fist: 1 – rotary fist; 2 – tightening plug; 3 – ABS sensor; 4 – rubber plug; 5 – bearing; 6 – antisplash casing; 7 – bolt, 10 N · m; 8 – wheel nave