4.2.3. Description of balancing of wheels

Fig. 4.10. Static steadiness: 1 – fluctuation of a wheel in the vertical plane; 2 – point of installation of balance weights; 3 – center of an axis; A – before correction; B – the correcting freights

There are two types of steadiness of the tire and a disk: static and dynamic. Static steadiness, as shown in the figure 4.10, represents equal distribution of weight on a disk. Statically unbalanced disks at the movement make vertical fluctuations. It eventually results in uneven wear of tires.

Fig. 4.11. Dynamic steadiness: 1 – fluctuation of a wheel in the vertical plane; 2 – point of installation of balance weights; 3 – center of an axis; A – before correction; B – the correcting freights

Dynamic steadiness, as shown in the figure 4.11, represents uniform distribution of weight concerning the plane of symmetry of a wheel, at the same time at rotation of a wheel there is no tendency to movement of a wheel here and there in the cross direction. Dynamic unbalance can become the reason of angular fluctuations of the operated wheels.

Internal part of a rim has to be cleared of dirt.

ATTENTION For high-quality balancing and prevention of traumatizing the operator of a flute of a protector it is necessary to clear of stones. Each tire has to be checked for existence of damages, and then is balanced according to recommendations of the manufacturer of the equipment.

The majority of electronic machines for balancing of wheels out of the car provide the big accuracy, than machines for balancing of wheels on the car. They are convenient and allow to make dynamic (in two planes) balancing. Though they do not correct unbalance of drums and disks that machines for balancing of wheels on the car allow, it is compensated by their accuracy, usually to within 1/8 ounces.

Ways of balancing of wheels on the car depend on the used equipment and the tool. When performing balancing follow indications of the producer of the corresponding equipment.

ATTENTION Speed of rotation of a wheel has to be limited to value of 55 km/h on a speedometer. This extreme value is necessary because the speedometer specifies only a half of the actual speed of a wheel when one of driving wheels rotates, and another – is stopped. If not to limit the speed of rotation of a driving wheel, then it can reach excessive values. It can lead to possible destruction of the tire or refusal of differential that, in turn, can become the reason of a trauma or damage of the car.

ATTENTION If the car is equipped with anti-blocking system of brakes, balancing of wheels on the car with the included ignition can lead to generation of a diagnostic code of malfunction of anti-blocking system of brakes, even when the system is serviceable. Never include ignition at rotation of a wheel.

Fig. 4.12. Scheme of shift of tires: A – shift of tires, including a spare wheel; B – shift of tires, without use of a spare wheel

To provide identical wear of tires, rearrange tires according to the scheme in the figure 4.12. Radial tires need to be rearranged periodically. Normalize pressure in tires.

NOTE Because of features of a design, radial tires tend to wear out quicker in a humeral zone, especially on forward wheels. It causes the necessity of shift.

NOTE It is applicable to cars with a spare wheel of the normal size