Disassembly of the transfer case was considered in the article - Disassembly of the transfer case VAZ-2123
Before inspection, thoroughly clean all parts of the transfer box with a brush and scraper, and then rinse. Blow the parts with compressed air.
Rinse and blow out the bearings especially carefully, preventing them from rapidly rotating from a jet of compressed air, so as not to damage them.
Crankcase and covers
There should be no cracks on the crankcase and covers, wear or damage (dents, chipping) should not be allowed on the surface of the bores for bearings.
Damages on the mating surfaces of the crankcase with covers can cause shaft misalignment and oil leakage.
Clean up minor damage with a file.
In case of significant damage or wear, replace the parts with new ones.
Check their condition carefully.
If even minor damage is found, replace the seals with new ones.
The wear width of the sealing lip should not exceed 1 mm.
Shafts. No damage is allowed on working surfaces, threaded parts and shaft splines.
Check the runout of the drive shaft and the front and rear axle drive shafts by mounting them on prisms and turning them by hand.
The runout of the end part of the thrust belts for bearings should be no more than 0.01 mm.
When checking the intermediate shaft, pay attention to the condition of the gear assembly and the speedometer drive gear.
No chipping or excessive tooth wear is allowed. Replace bad parts.
When inspecting the gears, check the condition of the teeth and seating surfaces.
It is not allowed to chip the teeth, their excessive wear.
Gear seating surfaces must be free of nicks or wear that cause large clearance.
Check the gear mesh clearance; the mounting gap should be 0.10 mm, the maximum allowable gap is 0.20 mm.
The mounting gap between the low gear and the bushing, as well as between the drive shaft and the high gear should be 0.05-0.10 mm, the maximum allowable is 0.15 mm.
When wear exceeds the allowable limits, replace the gears with new ones.
Ball and roller bearings must not show any damage on the raceways of the rings, cages, rollers or balls, as well as cracks and chips on the rings.
The radial clearance of the bearings must not exceed 0.05 mm.
When turning, a clean, dry bearing should not knock.
The move should be smooth, without jamming.
Replace damaged bearings.
It is not allowed to deform the forks and jam the rods in the crankcase holes.
Replace the parts of the clamps with new ones if traces of jamming are found.
Also replace the retainer springs if they lose elasticity.
The length of the spring under a load of 99.15-114.85 N (10.2-11.8 kgf) should be 19 mm, in the free state - 23.3 mm
Check for signs of seizing on the hub of the gear shifting clutch and especially on the sliding surfaces of the clutches, as well as on the splines of the differential case.
Clean up any nicks and burrs with a file.
Pay special attention to the condition of the ends of the coupling teeth; if they are broken or dented, preventing it from moving when shifting, replace the clutch.
Check the condition of the surface of the satellite shaft and the holes in the differential case; in case of minor damage, sand the surfaces with fine-grained sandpaper, and in case of significant damage, replace the parts with new ones.
Check the condition of the surface of the axle drive gear journals and their mounting holes in the differential housings, as well as the condition of the bearing surfaces on the adjusting washers and the end surfaces mating with them on the axle drive housings and gears.
Remove any damage found with a fine-grained sandpaper or a velvet file; Replace severely damaged or worn parts.
With the spring washer 14 removed (see figure 1), make sure that there is no radial movement of the circlips 8 in the grooves of the axle 13. If any play is found, replace the circlips.
Transfer case test
Test the assembled transfer case for noise, build quality and no oil leakage.
Check sequentially in higher and lower gears at the following frequency of rotation of the input shaft in both directions:
- - I mode — 100—200 min -1
- - II mode - 2000—2500 min -1
- - III mode - 3500—4000 min -1
In the second mode, carry out the test without load and under load with variable torque, and in modes I and III - without load.
Check the operation of the differential in the first mode, alternately braking the drive shafts of the front and rear axles until they stop.
Change gears and lock the differential with stationary shafts of the transfer case.
In the transfer case, it is not allowed: jamming, both gears and differential locks, knocking or uneven gear noise and oil leakage.
Transfer case assembly
We assemble the transfer case in the reverse order according to the article - Dismantling the transfer case VAZ-2123.
When assembling the center differential, we combine the marks on its housings.
We install the spring washer on the axis of the satellites from the side of the blind hole at the end of the axis.
Using pipe sections or tool heads of a suitable size, we press on the inner ring of the front bearing of the intermediate shaft.
We press on the bearing of the front axle drive shaft (the pipe must rest on the inner ring).
Pressing differential bearings
In the same way, we press the bearing of the rear axle drive shaft, the rear bearing of the intermediate shaft, the front and rear bearings of the input shaft
We install the drive and intermediate shafts in the transfer case at the same time.
We apply a thin layer of silicone sealant to all gaskets.
Having tightened the nuts of the rear bearings of the drive and intermediate shafts to the prescribed torque, we lock the nuts by pressing their shoulders into the grooves of the shaft shanks.
After assembly, fill with oil.
Tightening torques for fasteners of transfer case parts
Detail - Thread - Torque Nm (kgf.m)
- Nut for fastening the suspension bracket to the pillow axle - M10x1.25 - 26.5-32.3 (2.7-3.3)
- Nut for fastening the suspension bracket to the body - М8 - 15.0-18.6 (1.53-1.90)
- Nut for fastening covers of the transfer case housing, front axle drive housing, speedometer drive housing, control lever bracket - М8 - 14.7-24.5 (1.5-2.5)
- Differential lock switch - M16x1.5 - 28.4-45.0 (2.9-4.6)
- Bolt for fastening the forks to the gear shift rods - M6 - 11.8-18.6 (1.2-1.9)
- Bolt for fastening the forks to the differential lock rod - M12x1.25 - 11.7-18.6 (1.2-1.9)
- Bolt for fastening the driven gear - M10x1.25 - 66.6-82.3 (6.8-8.4)
- Nut for fastening the rear bearing of the input shaft and the rear bearing of the intermediate shaft - M18x1.5 - 96.0-117.6 (9.8-12.0)
- Nut for fastening the propeller shaft flange to the drive shaft and to the drive shafts of the front and rear axles - M16x1.5 - 96.0-117.6 (9.8-12.0)