6-1-2-proverka-i-regulirovka-parametrov-ustanovki-perednikh-koles.html

6.1.2. Check and adjustment of parameters of the unit of forward wheels

Their adjustment has to be made for obtaining the most exact parameters of the unit of wheels on the car having full weight at special stands. Adjustment of a forward suspension bracket is allowed with a mass of the equipped car.

Check and if necessary, adjustment of angles of installation of forward wheels are produced at a car run 1,5–2 thousand km, and further through each 30 thousand km of a run.

Need of adjustment of angles of installation of forward wheels arises in the following cases:

  – deterioration in stabilization of forward wheels (there is no spontaneous return of a steering wheel to a starting position at a car exit from turn);
  – withdrawal of the car at the rectilinear movement (a tendency of a constant deviation in one party irrespective of a side inclination of a profile of a roadbed);
  – the accelerated unilateral, step and spotty wear of a protector of tires of forward wheels;
  – a zadevaniye of tires at limit angles of rotation for the acting suspension bracket details, close located surfaces of a body and longerons of a frame.

Deterioration in stabilization of forward wheels usually is a consequence of violation of corners of a longitudinal inclination of an axis of turn of a telescopic rack and disorder of wheels.

Withdrawal of the car can be a consequence of a big difference (more than 0 °30') corners of a longitudinal inclination of an axis of turn of a telescopic rack and corners of disorder of the left and right operated wheels.

The accelerated unilateral wear of a protector of the tire happens at violation of a corner of disorder of wheels, uneven wear of tires with formation of step crests across a protector indicates violation of a convergence of wheels.

Zadevaniye of tires for the acting details of a forward suspension bracket can take place at violation of equality of limit angles of rotation of wheels in the left and right parties.

It is necessary to regulate the angles of installation of wheels on the car full, masses in such sequence:

1. Adjustment of a corner of a longitudinal inclination of an axis of turn of a telescopic rack.

2. Adjustment of a corner of disorder of wheels.

3. Adjustment of equality of limit angles of rotation of wheels.

4. Adjustment of a convergence of wheels.

Before adjustment of a suspension bracket it is necessary to check and if necessary to adjust:

1. Air pressure in tires.

2. Free wheeling of turn of a steering wheel.

3. Symmetric arrangement of spokes of a steering wheel.

4. Symmetric turning of a steering wheel or moving of a lath of the steering mechanism to both parties.

5. Beating of disks of forward wheels:

– radial – no more than 0,7 mm;
– axial – no more than 1 mm.

Besides it is necessary to consider that the details of a forward suspension bracket and the steering drive influencing the angles of installation of wheels have to be repaired or replaced by new.

After installation of the car on basic platforms of the stand, just before measurement of angles of installation, it is necessary "to prozhat" a suspension bracket in the direction from top to down by effort of 500-600 N (50–60 kgfs).

Check and if it is required, adjustment of angles of installation of wheels is made in the following order: at first check corners of a longitudinal inclination of an axis of turn and their difference, then corners of disorder and their difference and in the last turn of a convergence of wheels.

The angles of the maximum turn of an internal wheel on 40 ° are provided with an emphasis in the steering mechanism and therefore on the car are not regulated.