Mainshaft and Gears

DISASSEMBLY





1. Before disassembly, check 1st and 2nd main gear end plays.





Gear end play:

If not within specification, disassemble and check contact surface of gear, shaft and hub. Check clearance of snap ring groove.





2. Press out mainshaft rear bearing.





3. Remove thrust washer and snap ring.





4. Press out 5th main gear and 4th main gear.





5. Press out 3rd main gear and 2nd main gear.





6. Remove snap ring.





7. Remove 1st & 2nd synchronizer hub and 1st main gear.





8. Remove mainshaft front bearing.

INSPECTION
Gear And Shaft





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

Synchronizer





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





- Measure wear of 1st and 2nd double baulk rings.
a. Place baulk rings in position on synchronizer cone.
b. While holding baulk ring against synchronizer cone as far as it will go, measure dimensions "A" and "B".

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)

c. If dimension "A" or "B" is smaller than the wear limit, replace baulk ring.

Bearing





- Make sure bearings roll freely and are free from noise, cracks, pitting or wear.
- When replacing tapered roller bearing, replace outer and inner race as a set.





ASSEMBLY








1. Press on 1st main gear, 1st baulk ring and 1st & 2nd synchronizer hub.
- Pay attention to direction of 1st & 2nd synchronizer hub.
2. Select proper snap ring of 1st & 2nd synchronizer hub to minimize clearance of groove and then install it.

Allowable clearance of groove:
0 - 0.1 mm (0 - 0.004 inch)





Snap ring of 1st & 2nd synchronizer hub:





3. Install 2nd synchronizer cone, inner & outer baulk rings. Insert springs and 1st & 2nd coupling sleeve.
4. Install 2nd main gear.
- Ensure four protrusions of 2nd synchronizer cone are set in holes of 2nd main gear.





5. Press on 3rd main gear.
6. Press on 4th main gear.





7. Press on 5th main gear.
8. Select proper snap ring of 5th main gear to minimize clearance of groove and then install it.

Allowable clearance of groove:
0 - 0.15 mm (0 - 0.0059 inch)





Snap ring of 5th main gear:





9. Press on thrust washer and press on mainshaft rear bearing.
10. Press on mainshaft front bearing.
11. Measure gear end play as a final check.