Mainshaft and Gears

Disassembly





1. Before disassembly, measure gear end play with a suitable tool.
^ If end play is not within the specified limit, disassemble and check the parts.





2. Remove snap ring with a suitable tool.





3. Remove C-ring holder and mainshaft C-ring.





4. Press out mainshaft rear bearing from mainshaft using Tool.





5. Remove mainshaft thrust washer.
6. Remove snap ring from mainshaft. Then, remove reverse main gear assembly, reverse gear needle bearing, and reverse gear baulk ring.





7. Place bearing replacer between 5th & reverse synchronizer hub and 5th main gear, and press out both reverse gear bushing and 5th & reverse synchronizer assembly using Tool.
8. Remove 5th main gear, 5th gear baulk ring, and 5th gear needle bearing.





9. Place bearing replacer between 3rd and 4th main gears, and press out both 5th gear bushing and 4th main gear using Tool.





10. Remove mainshaft adjusting shim and spacer.
11. Place bearing replacer between 2nd main gear and 1st & 2nd synchronizer hub, and press out both 3rd and 2nd main gears.
12. Remove 2nd double cone assembly, 2nd gear bushing, and coupling sleeve assembly.





13. Place bearing replacer on 1st gear front side, and press out all of 2nd gear bushing, 1st & 2nd synchronizer hub, 1st main gear, and 1st double cone using Tool.
14. Remove 1st gear needle bearing.

Inspection
GEAR AND SHAFT





^ Check shaft for cracks, wear or bending.
^ Check gears for excessive wear, chips or cracks.

SYNCHRONIZERS





^ Check spline area of coupling sleeves, hubs and gears for wear or cracks.
^ Check baulk rings for cracks or deformation.
^ Check insert springs for wear or deformation.





^ If any crack, damage, or excessive wear is found on cam face of baulk ring or working face of insert, replace it.








^ Measure the movement (play, dimension "L") of 1st & 2nd coupling sleeve and 5th & reverse coupling sleeve with their end fixed and the other end lifted as shown in the figure. If the movement exceeds specification, replace the sleeve.





^ Measure clearance between baulk ring and gear.

BEARING





^ Make sure bearings roll freely and are free from noise, cracks, pitting or wear.





^ Measure wear of inner and outer baulk ring as shown.
- Place baulk rings in position on synchronizer cone.
- While holding baulk ring against synchronizer cone as far as it will go, measure dimensions "A" and "B" using Tool.
Standard "A": 0.6 - 0.8 mm (0.024 - 0.031 inch)
"B": 0.6 - 1.1 mm (0.024 - 0.043 inch)
Wear limit : 0.2 mm (0.008 inch)
^ If dimension "A" or "B" is smaller than the wear limit, replace outer baulk ring, inner baulk ring and synchronizer cone as a set.

Assembly





1. Install 1st gear needle bearing and 1st main gear onto mainshaft.
2. Install 1st double cone assembly onto mainshaft.





3. Install 1st & 2nd synchronizer hub with its three grooves facing the front side (1st main gear side) onto mainshaft.

CAUTION: Do not reuse 1st & 2nd synchronizer hub.





4. Install 1st & 2nd synchronizer hub using Tool.





5. Install insert spring onto 1st & 2nd coupling sleeve.





6. Install 1st & 2nd coupling sleeve with its chamfered surface facing the 1st main gear side onto 1st & 2nd synchronizer hub.





7. Install 2nd gear bushing with its flange surface facing 1st & 2nd synchronizer hub side using Tool.





8. Install 2nd needle bearing, 2nd double cone assembly, and 2nd main gear onto mainshaft using Tool.
9. Position 3rd main gear as shown, and install it using Tool.

CAUTION: Do not reuse 3rd main gear.





10. Install spacer and mainshaft adjusting shim onto mainshaft.
11. Select a mainshaft adjusting shim suitable to satisfy the following specification of dimension "L" and install it onto mainshaft.
Specification of dimension "L": 151.35 - 151.45 mm (5.9586 - 5.9626 inch)
Mainshaft adjusting shims: Refer to "Available Adjusting Shims".





12. Position 4th main gear as shown, and install it onto mainshaft.





13. Install 4th main gear onto mainshaft using Tool.

CAUTION: Do not reuse 4th main gear.





14. Install 5th gear bushing with its flange surface facing the 4th main gear side using Tool.





15. Install 5th needle bearing, 5th main gear, and 5th gear baulk ring onto mainshaft.





16. Being careful of the following points, install spread spring, shifting insert, and 5th & reverse synchronizer hub onto 5th & reverse coupling sleeve.





^ Pay attention to the shape of spread spring and shifting insert for correct assembly. Do not install spread spring hook onto the same shifting insert.
^ Install synchronizer hub with its three grooves facing the front side (5th main gear side).

CAUTION: Do not reuse 5th & reverse synchronizer hub.





^ Install 5th & reverse coupling sleeve with its chamfered surface facing the reverse main gear side.





17. Install 5th & reverse synchronizer hub assembly using Tool.





18. Install reverse gear baulk ring using Tool.
19. Install reverse gear bushing using Tool.
20. Install reverse gear needle bearing using Tool.





21. Install sub-gear, sub-gear washer, and snap ring onto reverse main gear.

CAUTION:
^ Pay attention to direction of sub-gear washer.
^ Do not reuse snap ring.





22. Install reverse main gear assembly onto mainshaft.
23. Select a thrust washer suitable to satisfy the following specification of dimension "M" as shown, and install it onto mainshaft.
Specification of dimension "M": 244.20 - 244.30 mm (9.6142 - 9.6181 inch)
Available thrust washers: Refer to "Available Thrust Washer".





24. Install mainshaft rear bearing using Tool.





25. Install mainshaft C-ring.
26. Using feeler gauge, measure the end play of mainshaft rear bearing with a suitable tool, and check if it satisfies the following specification.
End play: 0 - 0.06 mm (0 - 0.0024 inch)
Mainshaft C-rings: Refer to Specifications.





27. Install C-ring holder.





28. Install snap ring with a suitable tool.
29. Measure gear end play as a final check.