8.2.1. Check and adjustment of angles of installation of wheels

For the correct measurement of angles of installation of wheels the car has to be unloaded, and pressure in tires is brought to norm (the amount of fuel in a tank does not influence result of measurement).

Adjustment of angles of installation of wheels has to be carried out with big care as influences controllability of the car and the provision of a steering wheel.

Before carrying out measurements it is necessary to be convinced of lack of a side play:

— in wheel bearings;

— in the top fastenings of shock-absorbers;

— in rubber plugs of the longitudinal lever.

If in any of the listed elements there is a side play, it needs to be eliminated prior to measurements and adjustments.

Fig. 8.2. Places of check of a side play in a back suspension bracket

Fig. 8.3. Installation of the measuring equipment

Measurements of corners are carried out by means of the special equipment (fig. 8.3). At the same time under wheels establish mobile disks which should be used at measurement of side movement.

It is necessary for obtaining reliable result of measurement of disorder that the car settled down horizontally. It is necessary to rock several times with a force the car after installation of wheels on mobile disks up-down. It is necessary in order that the suspension bracket adopted the normal provision.

Disorder of wheels has to make — 40 '±30'. Values of disorder of the left and right wheels should not differ.

For adjustment of disorder:

Fig. 8.4. Arrangement of screws of adjustment of a convergence (1) and disorder (2) back wheels

— weaken an inhaling of a nut of the screw 1 (fig. 8.4) of adjustment of a convergence and, turning, release it. Release of the screw of adjustment of a convergence is important as it influences disorder;

Fig. 8.5. Parameters of adjustment of disorder of wheels

— weaken a nut (fig. 8.5) and turn the adjusting screw before obtaining right value of disorder;

— tighten a nut the moment of 80 N · m.

Fig. 8.6. Ways of definition of a convergence of wheels

The convergence of wheels should be checked and regulated only having convinced of correctness of installation of disorder. The convergence can be determined by two ways (fig. 8.6):

— measurement of a tilt angle of a nave; it has to be 9 '±6' on each wheel;

— measurement of a difference of distances between forward and back edges of wheels in points And — and, In — in and With — page. Nominal rates of a convergence: And — and = 1 — 5 mm; In — in = 0,8 — 4 m; With — with = 0,7 — 3,5 mm. The convergence of the left and right wheels can differ.

For adjustment of a convergence:

— weaken an inhaling of a nut of the screw 1 (fig. 8.4);

— tighten a nut the moment of 80 N · m also double-check a convergence.