1. Remove the synchronizer from the secondary shaft (see "Repair of the secondary shaft").
2. Before disassembling, mark the position of the coupling 3 relative to the hub 1. Carefully disassemble the synchronizer by removing the coupling from the hub. At the same time, make sure that the spring-loaded crackers 2 with balls do not fly apart in different directions.
3. Inspect the synchronizer parts. Chips and nicks on the splines of the hub and coupling are not allowed (pay special attention to the ends of the coupling teeth). Also, damage or signs of seizing on crackers, balls and springs are unacceptable. Replace defective parts or the synchronizer assembly.
4. Install the coupling on the hub in accordance with the previously applied marks.
5. In this case, the three large grooves on the splines of the coupling should coincide with the grooves of the hub for the clamps (with holes).
6. Lubricate the retainer spring with Litol-24 grease and insert it into the hole in the hub groove.
7. Lubricate the cracker with Litol-24 grease and insert the ball into its hole.
8. While compressing the spring, insert the cracker with the ball into the groove of the hub. The grooves a on the cracker must be directed outward, the spherical (large) surface b must face the coupling.
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9. Push the cracker so that the ball enters the grooves on the splines of the coupling.
10. Adjust the spring with a screwdriver so that it fits into the cracker hole. Install the remaining fasteners in the same manner.