RS6F51H

MAINSHAFT AND GEARS
DISASSEMBLY





1. Before disassembling, measure end play of 1st and 2nd main gears.
End play standard value
1st gear: 0.20 - 0.30 mm (0.0079 - 0.0118 inch)
2nd gear: 0.06 - 0.16 mm (0.0024 - 0.0063 inch)

CAUTION: If measurement is outside the standard range, disassemble to check contact surfaces of gear, shaft, and hub. Adjust with snap ring at assembly.





2. Remove the snap ring.
3. Remove C-ring holder, and then mainshaft C-ring.





4. Remove mainshaft rear bearing, adjust shim and 6th main gear.
5. Remove 5th-6th mainshaft spacer.





6. Remove 4th main gear and 5th main gear simultaneously.
7. Remove adjusting shim.
8. Remove spacer.





9. Remove 3rd main gear, 2nd main gear, 2nd gear needle bearing, 2nd bushing, 1st-2nd synchronizer assembly, 1st main gear, reverse main gear, 1st gear needle bearing, and 1st bushing simultaneously.

INSPECTION AFTER DISASSEMBLY
Mainshaft and Gears





Check items below. If necessary, replace them with new ones.
- Damage, peeling, dent, uneven wear, bending, and other nonstandard conditions of the shaft.
- Excessive wear, damage, peeling, and other non-standard conditions of the gears.

Synchronizer





Check items below. If necessary, replace them with new ones.
- Damage and unusual wear on contact surfaces of coupling sleeve, synchronizer hub, and shifting insert.
- Coupling sleeve and synchronizer hub must move smoothly.





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

Baulk ring clearance





- Double cone synchronizer (1st and 2nd)
Check clearance of outer baulk ring, synchronizer cone, and inner baulk ring of 1st and 2nd double cone synchronizers, following procedure below.

CAUTION: Outer baulk ring, synchronizer cone, and inner baulk ring as a set control clearance "A" and "B". If measurement exceeds service limit value, replace all of them as a set.





1. Using a dial gauge, measure clearance "A" at 2 or more points diagonally opposite, and calculate mean value.
Clearance A
Standard: 0.6 - 0.8 mm (0.024 - 0.031 inch)
Limit value: 0.2 mm (0.008 inch) or less





2. Using a dial gauge, measure clearance "B" at 2 or more points diagonally opposite, and calculate mean value.
Clearance B
Standard: 1.3 - 1.5 mm (0.051 - 0.059 inch)
Limit value: 0.2 mm (0.008 inch) or less

Bearing





Check items below. If necessary, replace them with new ones.
- Damage and rough rotation of bearing

ASSEMBLY





1. Install reverse main gear.





CAUTION: Be careful with orientation of reverse main gear.





2. Install 1st bushing.
3. Install needle bearing, and then 1st main gear.
4. Install spread spring, shifting insert and 1st-2nd synchronizer hub onto 1st-2nd coupling sleeve.





CAUTION:
- Be careful with orientation of synchronizer hub.





- Be careful with orientation of coupling sleeve.





- Be sure not to hook ends of 2 spread springs (front and back: 2 each) on same shifting insert.





5. Install 1st gear synchronizer assembly onto mainshaft, and synchronizer hub assembly onto mainshaft.

CAUTION:
- Outer baulk ring, synchronizer cone, and inner baulk ring on 2nd gear-side must have been removed.
- Be careful with orientation of coupling sleeve.





6. Install 2nd bushing.
7. Install outer baulk ring, synchronizer cone, and inner baulk ring on 2nd gear-side.
8. Install 2nd needle bearing and 2nd gear.





9. Install 3rd main gear.

CAUTION: Be careful with orientation of 3rd main gear.

10. Install 3rd-4th mainshaft spacer.





11. Select suitable adjusting shim so that dimension "C1" satisfies standard value below, and install it onto mainshaft.
Standard for: 173.85 - 173.95 mm (6.844 - 6.848 inch) dimension "C1"





Adjusting Shim

CAUTION: Only 1 adjusting shim can be selected.





12. Install 4th main gear.

CAUTION: Be careful with orientation of 4th main gear.





13. Install 5th main gear.

CAUTION: Be careful with orientation of 5th main gear.

14. Install 5th-6th mainshaft spacer.





15. Install 6th main gear.





16. Adjustment between 6th main gear and 6th main adjusting shim.
- Calculate thickness "S" of 6th main adjusting shim so that end play dimension between 6th main gear and mainshaft rear bearing is the dimension shown below.
End play: 0 - 0.1 mm (0 - 0.004 inch)
Dimension "S" = (S1 - S2) + End play
S: Thickness of adjusting shim
S1: Dimension from mainshaft reference face to mainshaft rear bearing press-fit end face
S2: Dimension from mainshaft reference face to 6th main gear end face

Adjusting Shim

CAUTION: Only 1 adjusting shim can be selected.

a. Using height gauge, measure dimension "S1" and "S2".
b. Install selected 6th main adjusting shim to mainshaft.





17. Install mainshaft rear bearing.





18. Install C-ring onto mainshaft, and check that end play of mainshaft rear bearing meets specifications.
End play standard value: 0 - 0.06 mm (0 - 0.0024 inch)
- If measurement is outside the standard range, reselect C-ring.





C-ring





19. Fit C-ring holder, and install snap ring.





20. Check end play of 1st and 2nd main gears.
End play standard value
1st gear: 0.20 - 0.30 mm (0.0079 - 0.0118 inch)
2nd gear: 0.06 - 0.16 mm (0.0024- 0.0063 inch)