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5. Install 1st gear synchronizer assembly onto mainshaft, and syn-
chronizer 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.
SCIA0941E
SCIA0942E
SCIA0943E
Standard for dimension C1
: 173.85 - 173.95 mm (6.844 - 6.848 in)
SCIA0944E
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MT-74
MAINSHAFT AND GEARS
Adjusting Shim
CAUTION:
Only one 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 snap ring onto mainshaft, and check that end play of 5th
main gear satisfies standard value.
●If measurement is outside the standard range, reselect snap
ring.
Snap Rings
Thickness Part number Thickness Part number
0.52 mm (0.0205 in)
0.60 mm (0.0236 in)
0.68 mm (0.0268 in)
0.76 mm (0.0299 in)32238 8H500
32238 8H501
32238 8H502
32238 8H5030.84 mm (0.0331 in)
0.92 mm (0.0362 in)
1.00 mm (0.0394 in)
1.08 mm (0.0425 in)32238 8H504
32238 8H505
32238 8H506
32238 8H507
SCIA0945E
SCIA0946E
End play standard value : 0 - 0.1 mm (0 - 0.004 in)
SCIA0947E
Thickness Part number Thickness Part number
1.85 mm (0.0728 in)
1.90 mm (0.0748 in)
1.95 mm (0.0768 in)
2.00 mm (0.0787 in)32204 8H500
32204 8H501
32204 8H502
32204 8H5032.05 mm (0.0807 in)
2.10 mm (0.0827 in)
2.15 mm (0.0846 in)
2.20 mm (0.0866 in)32204 8H504
32204 8H505
32204 8H506
32204 8H507
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15. Install mainshaft rear bearing.
16. Install C-ring onto mainshaft, and check that end play of main-
shaft rear bearing satisfies standard value.
●If measurement is outside the standard range, reselect C-ring.
C-ring
17. Fit C-ring holder, and install snap ring.
18. Check end play of 1st and 2nd main gears.
SCIA0948E
End play standard value : 0 - 0.06 mm (0 - 0.0024 in)
SCIA0949E
Thickness Part number Thickness Part number
2.535 mm (0.0866 in)
2.565 mm (0.1010 in)
2.595 mm (0.1022 in)
2.625 mm (0.1033 in)
2.655 mm (0.1045 in)
2.685 mm (0.1057 in)
2.715 mm (0.1069 in)
2.745 mm (0.1081 in)
2.775 mm (0.1093 in)
2.805 mm (0.1104 in)32348 8H800
32348 8H801
32348 8H802
32348 8H803
32348 8H804
32348 8H805
32348 8H806
32348 8H807
32348 8H808
32348 8H8092.835 mm (0.1116 in)
2.865 mm (0.1128 in)
2.895 mm (0.1140 in)
2.925 mm (0.1152 in)
2.955 mm (0.1163 in)
2.985 mm (0.1175 in)
3.015 mm (0.1187 in)
3.045 mm (0.1199 in)
3.075 mm (0.1211 in)32348 8H810
32348 8H811
32348 8H812
32348 8H813
32348 8H814
32348 8H815
32348 8H816
32348 8H817
32348 8H818
End play standard value
1st gear : 0.20 - 0.30 mm (0.0079 - 0.0118 in)
2nd gear : 0.06 - 0.16 mm (0.0024 - 0.0063 in)
SCIA0934E
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MT-76
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Assembly and Disassembly (RS6F51A)
ECS008C7
DISASSEMBLY
1. Before disassembling, measure end play of 1st and 2nd main
gears.
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 3rd & 4th mainshaft spacer.End play standard value
1st gear : 0.20 - 0.30 mm (0.0079 - 0.0118 in)
2nd gear : 0.06 - 0.16 mm (0.0024 - 0.0063 in)
SCIA0973E
SCIA0974E
SCIA0976E
SCIA0937E
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9. Remove 3rd main gear, 2nd main gear, 2nd gear needle bear-
ing, 2nd bushing, 1st-2nd synchronizer hub assembly, 1st main
gear, reverse main gear, 1st gear needle bearing, and 1st bush-
ing 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 non-
standard conditions of the shaft.
●Excessive wear, damage, peeling, and other non-standard con-
ditions 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.
SCIA0938E
SCIA1076J
SMT387A
SMT867D
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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, fol-
lowing 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.
2. Using a feeler gauge, measure clearance B at 2 or more points
diagonally opposite, and calculate mean value.
Bearing
Check items below. If necessary, replace them with new ones.
●Damage and rough rotation of bearing
SCIA0950E
Clearance A
Standard : 0.6 - 0.8 mm (0.024 - 0.031 in)
Limit value : 0.2 mm (0.008 in) or less
SCIA0951E
Clearance B
Standard : 0.6 - 1.1 mm (0.024 - 0.043 in)
Limit value : 0.2 mm (0.008 in) or less
SCIA1084E
MTF0041D
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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.
●Do not reuse 1st-2nd synchronizer hub.
SCIA0939E
SCIA0992E
SCIA0940E
SCIA0921E
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●Be careful with orientation of coupling sleeve.
●Be sure not to hook center projection of 2 spread springs
on same shifting insert.
5. Install 1st gear synchronizer assembly onto mainshaft, and syn-
chronizer 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.
SCIA0989E
SCIA1083E
SCIA0941E
SCIA0942E
SCIA0943E