2. Put the gearbox on for disassembly.
3. Remove the fifth gear housing.
4. Remove the gears and synchronizer of your transmission.
5. Remove the gearbox housing:
- Loosen the gearbox housing bolts.
- With a special nozzle (Bvi. 1934) remove the stroke switch (1).
- If equipped, remove locking pin (2) reverse gear shaft
- Engage third gear.
- Disconnect and remove the gearbox housing
6. Remove lock washers.
Versions with closed differential
7. Remove the fourth gear (1).
8. Remove the shift fork of the third-fourth gear with the rod assembly (2), tilted slightly to the side.
9. Remove input shaft (3).
10. Remove output shaft (4).
11. Remove the first-second shift fork with the stem (5).
12. Remove the fifth gear stem (6).
13. Remove the reverse gear fixing pins.
14. Remove reverse gear assembly (7).
15. Remove differential (8).
Versions with open differential
16. Turn the reverse gear shaft (9) in the direction of the arrow.
17. Remove the fifth gear rod (10).
18. Raise input shaft slightly (11) -
19.Remove the reverse gear shaft (12).
20. With a special tool (Bvi. 949) (13) remove the roll pin from the 3rd/4th shift fork.
21. Remove the shift fork of the third-fourth gear with the stem (14).
22.Simultaneously remove the input and output shafts with the yoke and the 1st/2nd shift shaft (15).
23.Remove the safety clips (16).
Checking gearbox components after removal
Checking the condition of the gears
When checking, pay special attention to the condition of the teeth, especially the chamfers and projections.
Make sure that:
- teeth (1) are not destroyed and do not have chips;
- ledges (2) not broken, worn or chipped;
- friction cone (3) has no scratches and signs of overheating (blue stains);
- inner walls (4) no signs of deformation or wear.
Checking the condition of the synchronizer hubs
Make sure that the cage slides easily onto the synchronizer hub and that the keys (5) in a good condition.
Checking the timing rings
Make sure that the teeth of the cam clutch (6) not worn or defective.
To check the operation of the synchronizer rings, press the ring against the friction cone and turn (7): The ring must not turn. Otherwise, it must be replaced with a new one.
Bearing check
Make sure the bearing (8) rotate properly
If the bearings rotate unevenly or are noisy, they must be replaced.