Axles with final drives (Fig. 1 and 2) are installed as a set (front and rear) on modifications of cars of the UAZ-31512 family with simultaneous replacement of the rear driveshaft
Maintenance of axles with final drives differs from the above-described technology for changing the lubricant in the pivot joints of the front axles, checking and changing the oil in the final drive housings, as well as adjusting the position of the drive gear 16 of the final drive and its bearings 5 and 7 (see. Fig. 1).
After adjusting the side clearance, it is necessary to check the engagement of the final drive gears on the contact patch bridge UAZ-3151. Assembly and adjustment of the rear axle UAZ-3151
Fig. 1. Rear axle with final drive
After a run of 50,000 km, during the next maintenance, it is recommended to tighten the bolts for fastening the driven gear 44 of the final drive and the driven gear 55 of the final drive, as well as the bolts for fastening the removable bearing housing 25 of the final drive.
The position of the gear 16 is adjusted by selecting the adjusting ring 15 of the required thickness.
When replacing the final drive gears and the large tapered bearing or only the final drive gears, measure the installation height of the large tapered bearing 5 under an axial load of 2–2.5 kN (200–250 kgf) and, if it is less than 32.95 mm, by some value, then increase the thickness of the adjusting ring by the same amount compared to that which was installed in the axle housing.
When replacing only a large tapered bearing 5, in order not to disturb the position of the gear, measure the mounting height of the old and new bearings and, if the new bearing has a higher mounting height than the old one, then reduce the thickness of the adjusting ring 15, and if less, then increase by the bearing height difference.
Regulate the preload in bearings 5 and 7 by selecting the adjusting ring 6 and tightening the nut 10.
If this fails, then change the number of spacers 13 and again, by selecting the ring and tightening the nut, achieve such a preload of the bearings that there is no axial movement of the gear, and the gear rotates without much effort.
Check with a dynamometer with the rubber cuff 8 removed.
With proper adjustment, at the moment of turning the gear through the hole in the flange, the dynamometer should show 10–20 N (1–2 kgf) for worn-in bearings and 25–35 N (2.5–3.5 kgf) for new ones.
Replace the grease in the steering knuckle joints in the following order:
- 1. Disconnect the flexible hose from the wheel cylinder of the brake mechanism and the tie rod ends from the levers, unscrew the bolts securing the clips of the o-rings of the ball joint and slide the clips with the o-rings onto the neck of the ball joint (Fig. 2).
- 2. Unscrew the nuts of the lever fastening studs or the bolts of fastening of the kingpin upper lining and remove the lever or lining and shims.
- 3. Unscrew the bolts securing the bottom trim, remove the trim with shims.
Fig. 3. Pivot puller
- 4. Using a puller (see Fig. 3), remove the pins from the steering knuckle housing and remove the housing assembly with the ball joint.
- 5. Carefully, without spreading the forks (so that the balls do not pop out), remove the hinge assembly with bearings and gear from the steering knuckle housing.
It is not necessary to remove the hinge from the steering knuckle housing and disassemble it without special need.
- 6. Remove used grease from the ball joint, joint and housing, rinse thoroughly with kerosene and apply fresh grease.
Reassemble in the reverse order of disassembly, observing the requirements for adjusting the pivots.
When installing the flexible brake hose, be careful not to twist it. After assembly, bleed the brake drive system (article "Bleed UAZ-3151» )
Disassemble the final drive in the following order:
- 1. After removing the hub with the brake drum, unscrew the coupling of the brake pipeline on the rear brake shield (on the front - a tee of connecting pipesok and flexible hose) from the wheel cylinder, unscrew the trunnion stud nuts and remove the spring washers, oil deflector, trunnion, trunnion gasket, spring gasket, brake assembly and brake shield gaskets.
- 2. Unscrew the nut 45 (see Fig. 1) fastening the bearing on the driven shaft of the final drive, unscrew the bolts of the final drive housing cover, remove the cover assembly with the shaft, remove the cover gasket and press the shaft out of the cover.
In contrast to the left final drive, the shaft 39 and nut 45 of the right drive have a left-hand thread. The nut with a left-hand thread is marked with an annular groove, and the shaft is marked with blind drilling with a diameter of 3 mm at the end of the splined end.
- 3. Unscrew the bolts securing the driven gear and remove the gear from the shaft 39.
- 4. Mark the position of the roller bearing housing 25 on the lug of the rear axle final drive housing, unscrew the housing mounting bolts, remove the bearing housing.
Do not remove the front axle final drive roller bearing housing unless absolutely necessary. (Further procedure for disassembling the final drive of the front axle, see above in the description of changing the grease in the steering knuckle joints.) Remove the retaining ring 22 of the ball bearing 21, axle shaft 18 and oil deflector 20 from the final drive housing.
- 5. Remove the circlip 26 of the roller bearing, the roller bearing 25, the drive gear 47 and the ball bearing from the axle shaft.
Assemble the final drive in the reverse order of disassembly, taking into account the following:
- - the bearing fastening nut 45 (Fig. 1) on the driven shaft of the front and rear final drives, as well as the nut 19 (see Fig. 2) of the bearing and gear fastening on the front final final drive drive shaft, after tightening, open into the groove of the shaft, and rings 26 for locking bearings on the axle shafts of the rear final drives, after installation in the groove, crimp;
- - tighten the bolts for fastening the wheel (driven gear) and the removable bearing housing with a torque of 64–78 Nm (6.5–8.0 kgf m), bolts for fastening the crankcase cover - 35–39 Nm (3.6–4, 0 kgf m).