Figure 6.30. Front wheel alignment
Front wheel alignment is shown in Figure 6.30.
Angle of longitudinal inclination of the axis of rotation
The pivot point is an imaginary line drawn through the axle of the front suspension strut and extended to contact with the road.
The specified angle is measured between the vertical and the axis of rotation. The angle is considered positive if the axis of rotation is tilted back from the top of the vertical. This angle is not adjustable in operation. Its value can be measured on a special stand and plays a role in the restoration of suspension or body elements after an accident.
Camber angle
This is the angle between the vertical and the plane of rotation of the wheel, as seen from the front of the vehicle.
The angle is considered positive if the plane of rotation of the wheel is deflected outward from the vertical, and negative if the plane of rotation of the wheel is deflected inside the vertical.
The camber angle is not adjustable, it is given for reference when restoring the kinematics of the front wheels as a result of an accident.
Angle of transverse inclination of the axis of rotation
This is the angle between the axis of rotation and the vertical drawn through the axle of the wheel and the contact patch of the wheel with the road.
The angle is not adjustable, it is given for reference in the event of restoration of the kinematics of the front wheels as a result of an accident.
Convergence
This is the difference in distance between the wheel rims at the front and rear, measured at the height of the hubs. If the distance ahead is less, the convergence is considered positive, and vice versa. Toe-in is measured in millimeters or degrees if the center line of the vehicle is taken as zero. The toe-in is adjusted by unscrewing or turning the steering tips, which changes the overall length of the steering rods.
Checking the angles of the front wheels
Checking the angles of the front wheels is an accurate and complex operation, which is practically inaccessible to the car owner for self-fulfillment. In auto centers for checking and adjustment, complex optical stands are used that can perform this work with great accuracy.
Wheel alignment angles that differ from those recommended by Renault lead to poor handling, vehicle stability and increased wheel tread wear.
It is recommended regularly, and after working on the suspension or steering, be sure to check and adjust the alignment of the front wheels.
For reference in Table. 6.1 shows the control values of the angles of installation of the front wheels, depending on the ground clearance.
Table 6.1. Front wheel alignment angles depending on ground clearance
Permissible angle difference between the right and left wheels is not more than 1°.
Convergence angle (mm) front wheels 0°16'±20', or (1,6±2,0) mm.