2. Check the condition of the shafts. In the presence of pitting (shells) bearing journals or wear marks, the shafts must be replaced. Shaft splines must not have dents, scuff marks or wear marks. Replace shafts with defective splines.
3. Check the condition of the gearbox gears. In the presence of chips and chipping of the teeth, scuffing in the internal holes and other damage, the gears must be replaced.
4. Check the condition of the bearings. In the presence of pitting (shells) on treadmills and rolling elements, traces of indentation of rolling elements on treadmills, damage to cages, replace bearings.
5. The radial clearance of ball and roller bearings must not exceed 0.05 mm. This can be checked with an indicator. Install the bearing on the shaft and the indicator leg on the top of the bearing outer race. Lightly press the bearing from the bottom up. The difference in indicator readings between the initial position and when the bearing is pressed is called the radial clearance.
6. Check up a condition of blocking rings of synchronizers. If there are nicks and chips on the gear rims or significant wear on the cones, replace the blocking rings.
7. Check the clearance between the gears and their respective locking rings. The minimum allowable gap is 0.6 mm. If it is less, the blocking ring must be replaced.
8. If scoring and deformation are found on the thrust washers and circlips, as well as if the circlips lose their elasticity, replace them.