Contents: Crankcase and covers ↓ Seals ↓ Shafts ↓ Gears ↓ Bearings ↓ Rods and forks ↓ Hubs, clutches and synchronizer…↓
Before inspecting the gearbox parts, clean them thoroughly with a brush or scraper, remove all deposits and clean the holes and splines from dirt. Then rinse to remove all oil residues. Blow the parts with a stream of compressed air and wipe them carefully. Blow the bearings especially thoroughly, directing the stream of compressed air so that the rings do not rotate quickly.
Crankcase and covers
There should be no cracks on the crankcase and no wear on the bearing seat surfaces (see table 5) or damage. The mating surfaces with the clutch housing and covers should also be free of damage that could cause axle divergence and insufficient sealing that could result in oil leakage. Minor damage can be repaired with a velvet file. If parts are damaged or their wear exceeds the permissible limits, replace them with new ones.
Check the condition of the front cover and whether the input shaft touches it when rotating. If the shaft and cover are not aligned, replace the damaged parts. Check whether the drain hole of the front cover is clogged and clean the drain plug.
Seals
There should be no damage or unevenness on the working edges, the permissible wear of the working edge in width is no more than 1 mm. Even if the damage is minor, replace them with new ones.
Shafts
The working surfaces and splines of the secondary shaft must not be damaged or subject to excessive wear (see table 5). The flexible coupling flange must slide freely on the splines. There must be no visible irregularities on the rolling surface of the needles at the front end of the secondary shaft and in the bore of the primary shaft. The intermediate shaft must not have chipping or excessive wear of the teeth. The surface of the reverse gear axle must be smooth, without signs of seizure. Remove minor irregularities on the surfaces with a set of sandpaper with a grain size of 10-M40. In case of major damage and deformation, replace the shaft with a new one.
Gears
The gears must not have any damage or wear of the teeth exceeding the permissible lateral clearance in the engagement specified in Table 5. Pay special attention to the condition of the ends of the teeth on the synchronizer rings. The contact patch between the teeth of the gears in the engagement must extend over the entire working surface, which must be smooth, without visible signs of wear. In addition, check the clearance in the engagement between the gears (see table 5).
Bearings
Must be in perfect condition. Their radial clearance must not exceed 0.05 mm. When checking, press the inner ring to the outer ring with your fingers and rotate one of them in both directions, while the rolling must be smooth. No damage is allowed on the surfaces of the balls (rollers) and the raceways of the rings. Replace faulty bearings with new ones.
Rods and forks
Deformation of the gear shift forks is not allowed. The rods must slide freely without significant clearance in the crankcase holes. Check the condition of the locking crackers, springs and locking balls. Replace parts with new ones that show visible signs of seizing or wear.
Hubs, clutches and synchronizer locking rings
Original source is on the resource (VazBook.ru)
Check for signs of seizing on the hubs of the gear engagement clutches, especially on the sliding surfaces of the clutches. Pay particular attention to the condition of the ends of the clutch teeth. Excessive wear of the surface of the locking rings when they rest against the synchronizer clutch is not allowed. Fix faults that prevent free sliding with a velvet file. Replace worn parts with new ones.
The dimensions of the main mating parts of the gearbox and the limits of permissible wear are given in Table 5.