Synchronizers Cleaning and Inspection

Synchronizers Cleaning and Inspection





Note:
When servicing the synchronizers, retain them in the order that they are removed. Mark the parts to ensure the correct position for inspection and assembly.

1. Clean all the synchronizer parts in a suitable cleaning solvent and air dry all the parts.

2. Inspect the 1st/2nd gear, 3rd/4th gear, and 5th gear synchronizer hubs for a force fit on the main shaft.

3. Replace synchronizer hubs that do not require a force fit.

4. Inspect the synchronizer hubs for wear on the external splines. A stepped effect on the teeth, due to wear, may cause shift concerns.

5. Replace a worn hub.

6. Correct the cause, such as, but not limited to the following conditions:

* Engine related vibrations

* Driving at a low speed in a high gear

* Defective vibration damper or crankshaft





7. Inspect the synchronizer sleeve teeth (1) for the following conditions, which may cause shift concerns:

* Grated teeth

* Chipped off teeth

* Blunted teeth

8. Inspect the synchronizer sleeve detent stops (2) for wear or for being chipped off.

9. Replace the synchronizer assembly if the teeth or stops show the above conditions.





10. Inspect the synchronizer blocker rings for worn away grooves (1).

11. Replace the blocker ring assembly if the blocker ring grooves are worn.





12. Inspect the synchronizer blocker rings for worn shift teeth.

13. Inspect the internal ring for being warped or damaged.

14. Inspect the outer ring for worn grooves.

15. Replace the synchronizer assembly for any of the above conditions.





16. Install the synchronizer blocking rings to the correct speed gear.

17. Inspect the braking effect of the blocking ring. Turn the blocking ring in one direction while pushing to the gear cone. Ensure the ring locks.

18. If the ring does not lock, replace the synchronizer assembly.





19. Inspect the pressure pieces (1) for wear or damage.

20. Replace the worn pressure pieces.