Shock absorber knocking - main causes

Many drivers are familiar with the phenomenon of shock absorber knocking.

Unpleasant «sound effect», unfortunately, does not appear immediately. You can only hear the knocking sound after a long period of malfunction. The problem is not difficult to rectify and can be solved by repairing or replacing the old shock absorber.

Functions of the shock absorber

A shock absorber – is a device that serves to dampen vibrations and provide protection to the vehicle from shocks that occur when travelling on rough roads. If the shock absorbers are faulty, it's hard to have a pleasant ride.

With time, the shock absorbers start to knock, which affects the comfort of the passengers, but most importantly – it increases the accident rate. The main reason – a significant increase in braking distance, reducing the stability of the car. When shock absorbers are defective, when making turns and other difficult manoeuvres, the level of grip of the wheel with the road is reduced. By identifying the cause of the knocking sounds, you can prevent possible negative consequences.

Main Causes

• It is necessary to make sure that there is no oil leakage, its leakage – one of the main causes of failure. When leakage is present, the shock absorber should be changed.
• By pressing the fender of the car, perform a simple rocking test. A failed shock absorber cannot sufficiently dampen the vibrations, the car will remain rocking for a long time.
• An unpleasant knocking noise may indicate a dangerous level of wear on the device or mechanical deformation of the shock absorber. In such a malfunction it is necessary to repair or replace the shock absorber when the mileage is 50 thousand kilometres.
• An unpleasant knock can indicate a dangerous level of wear of the device or mechanical deformation of the shock absorber.
• Another factor in the appearance of knocking can be a leakage of hydraulic fluid in the external cylinder, since air will enter the place that has become free. Remove the cause of knocking can be removed after pumping the shock absorber. Pumping is performed both independently and with the help of specialists of the car service.
• An uncommon phenomenon is the appearance of knocking in winter. The knock appears at sub-zero temperatures due to oil freezing. In such a situation it is necessary to warm up the shock absorber as soon as possible. In winter, use a shock absorber fluid that has a low pour point and low viscosity, which does not change with temperature fluctuations.
• The shock absorber should also be checked for its integrity. The cause of knocking may be a malfunction of some elements of the device: pipe breakage, damage to the thread of the stem, detachment of the shock absorber.

What to do when a shock absorber has just been installed, but you hear knocking noises?

Make sure the installation was done correctly, the nuts are tightened well and there is no stem play. If all is well and the knocking is still present, the shock absorber has been fitted with old bushings or unsuitable bushings for this type of device. To avoid such problems, it is better to buy shock absorbers with a set of bushings.

The MS1000+ gives you the opportunity to carry out diagnostics quickly and efficiently. The bench diagnoses all types of shock absorbers, determines their need for repair, and determines the degree of performance before and after repair.

Diagnostics is carried out in two modes: manual or automatic. The automatic test takes approximately one minute. The results can be seen on the touch screen display of the stand. The diagnostic equipment is easy to use. The MS1000+ manual describes the MS1000+ in detail, with information and tips to help you get the job done.

Benefits of MS1000+ diagnostics:

• Ability to test any type of shock absorber;
• Diagnostics can be performed at various speeds with additional loading;
• Comparison of test results before and after repair;
• Saving and printing test results;
• Accounting for shock absorber temperature during diagnostics;
• Comprehensible and simple software

Purchase of MS1000+ will help to carry out high-quality, accurate and fast diagnostics of shock absorbers, and thus increase the flow of customers and profits of the workshop.