Mainshaft and Gears
Disassembly and AssemblyDISASSEMBLY
1. Before disassembling, measure the 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 the measurement is outside the standard value, disassemble to check the contact surfaces of the gear, shaft, and hub. Adjust with the correct snap ring size at assembly.
2. Remove the snap ring.
3. Remove the C-ring holder, and then mainshaft C-ring as shown.
4. Remove the mainshaft rear bearing using Tool as shown.
5. Remove the snap ring.
6. Remove 4th main gear and 5th main gear simultaneously using Tool as shown.
7. Remove adjusting shim.
8. Remove 3rd-4th mainshaft spacer.
9. Remove 3rd main gear, 2nd main gear, 2nd needle bearing, 2nd bushing, 1st-2nd synchronizer hub assembly, 1st main gear, reverse main gear, 1st needle bearing, and 1st bushing simultaneously using Tool as shown.
INSPECTION AFTER DISASSEMBLY
Main Shaft and Gears
Check parts listed. 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 parts listed. 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.
NOTE: The mean value is the middle value of a set of measurements between the highest and lowest values. It is calculated by adding the highest and lowest measured value and dividing their sum by two: [(high value) + (low value)] /2 = mean value.
CAUTION: Outer baulk ring, synchronizer cone, and inner baulk ring act as a set to control the clearances "A" and "B". If the measurement exceeds the service limit value, replace all of them as a set.
1. Using a dial gauge and Tool, measure clearance "A" at two or more points diagonally opposite, and calculate the 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 feeler gauge, measure clearance "B" at two or more points diagonally opposite, and calculate the mean value.
Clearance "B"
Standard : 0.6 - 1.1 mm (0.024 - 0.043 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 using Tools as shown.
CAUTION: Install the reverse main gear with the specified orientation as shown.
2. Install 1st bushing using Tools as shown.
3. Install needle bearing, and then 1st main gear.
4. Install spread spring, shifting insert and new 1st-2nd synchronizer hub onto 1st-2nd coupling sleeve.
CAUTION:
^ Install with orientation of synchronizer hub as shown.
^ Do not reuse the 1st-2nd synchronizer hub.
^ Install with orientation of coupling sleeve as shown.
^ Do not to hook the ends of the two spread springs (front and back have two each) on same shifting insert as shown.
5. Install 1st gear synchronizer assembly onto mainshaft, and synchronizer hub assembly onto mainshaft using Tools as shown.
CAUTION:
^ Outer baulk ring, synchronizer cone, and inner baulk ring on 2nd gear-side must have been removed.
^ Install with orientation of coupling sleeve.
6. Install 2nd bushing using Tools as shown.
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 using Tools as shown.
CAUTION: Install with orientation of 3rd main gear as shown.
10. Install 3rd-4th mainshaft spacer.
11. Select a suitable adjusting shim so that the dimension "C1" satisfies the standard value below, and install it onto the mainshaft as shown.
Standard for dimension "C1": 173.85 - 1 73.95 mm (6.844 - 6.848 inch)
CAUTION: Only 1 adjusting shim can be selected.
Adjusting Shims
12. Install 4th main gear using Tools as shown.
CAUTION: Install with orientation of 4th main gear as shown.
13. Install 5th main gear using Tools as shown.
CAUTION: Install with orientation of 5th main gear as shown.
14. Install snap ring onto mainshaft, and check that end play of 5th main gear satisfies standard value as shown.
End play standard value : 0 - 0.1 mm (0 - 0.004 inch)
^ If measurement is outside the standard value, reselect the required size snap ring.
Snap Rings
15. Install mainshaft rear bearing using Tools as shown.
16. Install C-ring onto mainshaft, and check that end play of mainshaft rear bearing meets specification as shown.
End play standard value : 0 - 0.06 mm (0 - 0.0024 inch)
^ If measurement is outside the standard value, reselect the required size C-ring.
C-rings
17. Fit C-ring holder, and install snap ring as shown.
18. 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)