When pressing out the hub, the bearing may be disassembled and the outer half of the inner ring may remain on the hub. In this case, it is removed with a universal puller. There are two special recesses in the hub for this purpose. Then, the retaining rings 4 are removed (figure 101) and using mandrel 67.7853.9574 press out the bearing from the steering knuckle.
The new bearing is installed in the following order: install the outer retaining ring 4 (see figure 101) into the steering knuckle 6 and press in the bearing 5. At the same time, make sure that the mandrel 1 (figure 102) pressed only on the outer ring 2, otherwise it may be damaged. Then install the inner retaining ring and start pressing the hub with a technological mandrel. When pressing it, mandrel 4 (figure 103) must necessarily rest on the inner ring of the bearing.
After installing the steering knuckle assembly with the hub on the car, install a new or used nut, but on another car, and tighten it to a torque of 196.0-235 N·m. Then lock the nut.
Installing the suspension strut into the fixture 67.7823.9545 (figure 104), compress the suspension spring. Holding the rod with the A.57070 key, unscrew the nut on the rod. Remove the upper support 5 (figure 105) assembled with collars 4 and 6, support washer 7, ring 8 and bushing 9. Having unloaded spring 11, remove it and upper support cup 10, and then buffer 3 of compression stroke with casing 2. Before further disassembling rack 1, check its condition. With the rack in vertical position (with the stem up) perform several full stretching-compression strokes, after which the rod should move without dips or jamming. The rebound force should be greater than the compression force. There should be no knocking or other extraneous noise. Liquid leakage, deformation or destruction of the strut body, support cup, or brackets are also not allowed. Minor sweating in the upper part of the strut body is not a sign of a malfunction and is not a reason to replace or repair the suspension strut.
A more accurate assessment of the strut's performance is carried out on a dynamometer stand using the diagram taken, as indicated in the previous section.
If it is necessary to repair the rack, clamp its bracket in a vice so that the cheeks of the bracket are perpendicular to the jaws of the vice (figure 106). With this type of fastening, the possibility of deformation of the rack is excluded. Disassemble the rack using the tool kit 67.7824.9518, in the following order:
- unscrew with key 1 (67.7811.9512) (see figure 106) nut 2 of the housing, remove the rod 9 from the housing of the rack (see figure 98) assembled with seal 2, guide bushing 3 of the rod, compression stroke limiter and parts of the rebound valve and bypass valve;
- remove cylinder 6 from the rack housing together with the compression valve and drain the liquid from the cylinder;
- having installed the compression valve in the mandrel from the 67.7824.9518 kit, clamp it in a vice and slightly rock the cylinder by hand until the compression valve separates from the cylinder;
- clamp the rod in a vice by the chamfers on its tail and unscrew the nut 16 (see figure 98) of the return valve, then remove the return valve parts 13, 14, 15, piston 12 and the bypass valve parts 10, 11 from the rod; having freed the rack body from the vice, drain the liquid from it;
- the compression valve is disassembled, for which the clip 17 is removed, and then the spring, plate 18 and disks 19 of the compression valve are successively removed from the housing.
The front suspension strut assembly is carried out in the reverse order of disassembly, taking into account the following:
- ensure the cleanliness of the work area and all parts of the rack;
- make sure that there are no foreign impurities in the liquid, filter it if necessary, make sure that the thread of the recoil valve nut is not damaged when unscrewing it with a punched rod;
- inspect the rod at the point of kerning; if the thread deformation is large and does not allow the return valve nut to be screwed on without damaging its thread, then the rod thread is calibrated with a die;
- the front shock absorber rebound valve throttle disc has six slots on the outside diameter, and the rear shock absorber throttle disc has four slots;
- the throttle disc of the front suspension strut compression valve has three grooves along the inner diameter, and the throttle disc of the rear shock absorber has two;
- the rebound valve nut is tightened to a torque of 12.7-17.5 N·m, after which it is counter-locked by punching the threaded end of the rod in previously undeformed places;
- after assembling the rebound valve, check for free movement of the bypass valve plate;
- it is recommended to replace the rod seal with a new one;
- working surface of the seal (between the sealing edges) fill with SHRUS-4 grease in the amount of 0.3-0.4 g;
- (270±5) cm³ of MGP-10 liquid is poured into the strut housing and into the cylinder, and (143±±) cm³ of the same liquid is poured into the rear shock absorber;
- after assembling the compression valve, make sure that the valve plate and discs have free movement;
- the compression valve is pressed into the cylinder using a tubular mandrel with an internal diameter of 33 mm, after which the presence of free movement of the plate and disks is once again verified;
- to install and press the rod guide bushing, use a tubular mandrel with an internal diameter of 35 mm;
- the strut housing nut is tightened with the rod fully extended using the 67.7811.9512 key, tightening torque 117-147 N·m, for the rear shock absorber the tightening torque is 69-88 N·m;
- springs of the same class are installed on the suspension.
Springs are divided into two classes according to their length under the control load: A and B. Class A springs are marked with yellow paint on the outer side of the coils, and class B springs are marked with green paint. In exceptional cases, if class A springs are installed on the front suspension, and there are no springs of this class for the rear suspension, it is permissible to install class B springs on the rear suspension. But if class B springs are installed on the front suspension, then only class B springs are installed on the rear suspension.
Notes
1. See section. "Gearbox assembly".
2. A cylindrical mandrel with a diameter of 25 mm with a support belt with a diameter of 60 mm and a width of 6 mm has a shank with a length of 14 mm and a diameter of 25 mm.