Adjusting the steering mechanism includes adjusting the propeller bearings and adjusting the meshing of the gear sector and the rack nut
Start adjusting the mechanism with the screw bearings in the following sequence:
- - remove the steering gear (see the article "How to repair the MAZ steering gear");
- - drain the working fluid from the steering mechanism by unscrewing the drain plug;
- - fix the steering mechanism in a vice for the body lugs in a horizontal position;
- - by turning the input shaft (Fig. 1), set the nut-rail and sector 8 to one of the extreme positions (left or right);
- —define the torque required to rotate the input shaft from the extreme position to the middle position (approximately 30°).
If the torque is less than 0.9 Nm, it is necessary to adjust the preload in the bearings 1 by reducing the number of spacers 9.
After adjustment, the torque required to rotate the input shaft should be within 0.9-1.5 Nm (0.10-0.15 kgf.m).
To check for backlash in the gearing, rotate the input shaft to set the rack nut and the gear sector to the middle position (the total number of revolutions of the input shaft is divided in half), install the bipod on the sector 8 shaft.
By rocking the bipod in both directions, determine the presence of backlash (if there is a backlash, a knock is heard in the gearing and, in addition, the sector shaft rotates, and the input shaft is stationary).
The presence of backlash can also be determined by turning the input shaft to the left and right at the beginning of the torsion bar twist, while locking the sector shaft.
To adjust the gearing, it is necessary to remove the covers 19 and 15 and turn the liners 12 clockwise by the same angle (when viewed from the side of the sector shaft) so as to eliminate the gap in the gearing.
Install the covers 15 and 19 in such a way that the pins 14 enter the holes in the inserts 12 located in the same diametrical plane with the threaded holes in the body 3 for attaching the covers.
If the holes 11 slightly mismatch with the threaded holes of the body 3, turn the inserts 12 in one direction or another until the above holes match, paying attention to the absence of a gap in the gearing.
Pins 14 should be placed opposite each other in one line.
After adjustment, cover 15 (covers 10 and 16 - for the steering mechanism, Fig. 2) can be rotated 90, 180 and 270 degrees relative to the original position during installation.
After installing the covers, the torque required to turn the input shaft in the middle position should be between 2.9-4.5 Nm (0.29-0.45 kgcm)
After carrying out the adjustment work, install the steering gear on the car and, connecting it to the steering column and hydraulic cylinder, check the operation of the steering.
With proper adjustment (with adjusted steering linkages, front wheel hub bearings and pivot joints, the front axle beam - steering knuckle), the force on the steering wheel rim when turning the steered wheels in place on an asphalt surface should be with the engine running 98 -118 N (10-12 kgf) and the free steering angle is not more than 10...12˚.
During operation, it is allowed to increase the free play of the steering wheel, but not more than 18 °.
The angles of rotation of sector 7 (Fig. 3), at which the pressure limiting valve 13 is actuated, are adjusted directly on the vehicle as follows:
To increase the angles of rotation of sector 7 and, consequently, of the steered wheels to the left to a predetermined value, it is necessary to unscrew the lock nut 24 until it comes out of contact with the body 23 and turn the plug 22 counterclockwise, while the nut 21 with the stem 20 and the lever 19 will move down, ensuring the removal of the roller 18 from the side face 17 of sector 7.
After making the adjustment, tighten the locknut 24, holding the plug 22 from turning.
To reduce the angles of rotation of sector 7 and, consequently, the steered wheels to a given value to the left, it is necessary to unscrew the lock nut 24 until it comes out of contact with the body 23 and turn the plug 22 clockwise, while the nut 21 with the stem 20 and the lever 19 will move upwards, ensuring that the roller 18 approaches the side face 17 of sector 7
After making the adjustment, tighten the locknut 24, keeping it from turning and the cork is 21.
To increase or decrease the angle of rotation of the sector and, consequently, the steered wheels to a given value to the right, by similar adjustment, the roller 26 with the lever 25 is removed or approaches the edge 27 of sector 7.