This work requires special equipment and cannot be done by yourself, so here we will only outline the basic concepts.
Convergence
Toe-in refers to the transverse distance between the wheels. As a general rule, the front wheels should have a positive toe-in, as they tend to move outward in a straight line due to rolling resistance. When specifying a positive toe-in of the front wheels, the distance between them is measured at the height of the centers of the wheels - in front it should be slightly less than in the back.
With negative toe-in of the front wheels, the distance measured at the height of their centers should be slightly greater at the front than at the rear.
At "Mercedes" both front and rear wheels can be adjusted for positive toe.
The collapse of the front wheels and the angle of inclination of the kingpins in the transverse plane:
Front axle:
- St - Collapse.
- Sp - Angle of inclination of the kingpin in the transverse plane.
- LR - Turning radius.
- 2 - Cross.
- 4 - Lower control lever.
- 5 - Swivel fist.
- 6 - Upper control lever.
- 7 - Lower ball joint.
- B - Upper ball joint.
- 19 - Eccentric bolt for adjusting the camber.
- 49 - Support tube.
Properly installed camber and the angle of inclination of the kingpins in the transverse plane soften the shocks transmitted from the bumps in the road to the steering, reduce the friction of the tires on the road when cornering.
Camber is the angle between the plane of the wheel and the vertical. With positive camber, the distance between the front wheels is smaller at the bottom than at the top. At "Mercedes" the turning radius is zero.
The angle of inclination of the kingpins of the front wheels in the longitudinal plane:
Front axle:
- NL - Angle of inclination of the kingpin in the longitudinal plane.
- VLV - rear camber.
- 1 - Side element.
- 2 - Cross:
- 4 - Lower control lever.
- 5 - Swivel fist.
- 6 - Upper control lever.
- 8 - Upper ball joint.
- 10 - Stabilizer.
- 19 - Eccentric bolt for adjusting the camber.
- 21 - Rubber bushing of the stabilizer.
- 48 - Ball joint.
- 48a - Ball pin for adjusting the angle of rotation of the front wheels.
- 49 - Support tube.
The angle of inclination of the king pin in the longitudinal plane is determined relative to the vertical drawn through the wheel axle. The tilt angles of the pivots, both in the longitudinal and in the transverse planes, are adjusted using two eccentric bolts.
The angle of inclination of the kingpins in the longitudinal plane affects how good the front wheels are "are holding" movement in a straight line. An angle that is too small causes deviation from a straight line on poor roads or in high wind conditions, and also prevents the steering mechanism from returning to the center position after completing a turn.
Front wheel alignment
An inspection hole or a lift is required to adjust the angles of the front wheels. Before starting measurements, check the following:
Are the tire pressures correct?
The car must be empty, the fuel tank is full, the spare wheel and tool kit must be in place.
Check steering adjustment.
Check tie rods for excessive play.
Check wheel suspension for excessive play.