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MT-77
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6. Press out 4th main gear and 5th main gear using the drift and a
puller.
7. Remove 4th main gear adjusting shim.
8. Remove 3rd-4th mainshaft spacer.
9. Press out 3rd main gear, 2nd main gear, 2nd needle bearing,
2nd main gear bushing, 1st-2nd synchronizer hub assembly, 1st
main gear, 1st needle bearing, and 1st main gear bushing
reverse main gear using the drift.
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.
SCIA0937E
SCIA0938E
SCIA1076J
SMT387A
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MT-78
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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)
Follow the instructions below and inspect the clearance of outer
baulk ring, synchronizer cone, inner baulk ring.
CAUTION:
Outer baulk ring, synchronizer cone, and inner baulk ring
control clearances “A” and “B” as a set. Replace them as a
set if they are outside the limit value.
1. Measure clearance A at 2 or more points diagonally opposite
using a dial gauge, and calculate mean value.
2. Measure clearance B at 2 or more points diagonally opposite
using a feeler gauge, and calculate mean value.
Triple cone synchronizer (2nd)
Follow the instructions below and inspect the clearance of outer
baulk ring, synchronizer cone, inner baulk ring.
CAUTION:
Outer baulk ring, synchronizer cone and inner baulk ring
control clearances “A”, “B” and “C” as a set. Replace them
as a set if they are outside the limit value.
SMT867D
SCIA0950E
Clearance A
Standard value : 0.6 - 0.8 mm (0.024 - 0.031 in)
Limit value : 0.2 mm (0.008 in)
PCIB0818E
Clearance B
Standard value : 0.6 - 1.1 mm (0.024 - 0.043 in)
Limit value : 0.2 mm (0.008 in)
SCIA1084E
PCIB0603E
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MAINSHAFT AND GEARS
MT-79
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1. Measure clearance “A” at 2 points or more on the opposite side
using a feeler gauge when pressing baulk ring toward clutch
gear taper cone. Then calculate the average.
2. Measure clearance “B” at 2 points or more on the opposite side
using a feeler gauge. Then calculate the average.
3. Measure clearance “C” at 2 points or more on the opposite side
using a feeler gauge when pressing baulk ring toward clutch
gear taper cone. Then calculate the average.
Bearing
Check items below. If necessary, replace them with new ones.
Damage and rough rotation of bearingClearance “A”
Standard value : 0.6 - 1.2 mm (0.024- 0.047)
Limit value : 0.3 mm (0.012 in)
PCIB0808E
Clearance “B”
Standard value : 0.6 - 1.1 mm (0.024 - 0.043)
Limit value : 0.2 mm (0.008 in)
PCIB0605E
Clearance “C”
Standard value : 0.7 - 1.1 mm (0.028 - 0.043 in)
Limit value : 0.3 mm (0.012 in)
PCIB0809E
MTF0041D
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MT-80
MAINSHAFT AND GEARS
ASSEMBLY
1. Press in reverse main gear using the drifts and the press stand.
CAUTION:
Be careful with orientation of reverse main gear.
Do not reuse reverse main gear.
2. Press in 1st main gear bushing using the drifts and the press
stand.
3. Install 1st needle bearing, and then 1st main gear.
4. Install 1st-2nd spread spring, 1st-2nd shifting insert and a new
1st-2nd synchronizer hub onto a new 1st-2nd coupling sleeve.
CAUTION:
Be careful with orientation of 1st-2nd synchronizer hub.
Do not reuse 1st-2nd synchronizer hub.
SCIA0939E
SCIA0992E
SCIA0940E
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Be careful with orientation of 1st-2nd coupling sleeve.
Do not reuse 1st-2nd coupling sleeve.
Be sure not to hook center projection of 2 spread springs
on same 1st-2nd shifting insert.
5. Install 1st inner baulk ring, 1st synchronizer cone, 1st outer
baulk ring onto mainshaft, and then press in 1st-2nd synchro-
nizer hub assembly onto mainshaft using the drifts and the press
stand.
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. Press in 2nd main gear bushing using the drift and the press
stand.
7. Install 2nd outer baulk ring, 2nd synchronizer cone, and 2nd
inner baulk ring.
8. Install 2nd needle bearing and 2nd main gear.
9. Press in a new 3rd main gear using the drift and the press stand.
CAUTION:
Be careful with orientation of 3rd main gear.
Do not reuse 3rd main gear.
10. Install 3rd-4th mainshaft spacer.
PCIB0803E
SCIA1083E
SCIA0941E
SCIA0942E
SCIA0943E
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MT-82
MAINSHAFT AND GEARS
11. Select 4th main gear adjusting shim so that dimension “C1” sat-
isfies the standard value below, and install 4th main gear adjust-
ing shim onto mainshaft. Refer to MT-101, "
4TH MAIN GEAR
ADJUSTING SHIM" .
CAUTION:
Only one adjusting shim can be selected.
12. Press in a new 4th main gear using the drifts.
CAUTION:
Be careful with orientation of 4th main gear.
Do not reuse 4th main gear.
13. Press in a new 5th main gear using the drifts.
CAUTION:
Be careful with orientation of 5th main gear.
Do not reuse 5th main gear.
14. Install 5th-6th mainshaft spacer.
15. Press in 6th main gear using the drifts.
CAUTION:
Do not reuse 6th main gear. Standard value for dimension C1
: 173.85 - 173.95 mm (6.844 - 6.848 in)
PCIB0804E
SCIA0945E
SCIA0946E
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MT-83
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16. Select 6th main adjusting shim and then install it onto mainshaft.
Calculate thickness “S” of 6th main adjusting shim following
the procedure below so that end play dimension between 6th
main gear and mainshaft rear bearing becomes the dimen-
sion shown below. Refer to MT-102, "
6TH MAIN GEAR
ADJUSTING SHIM" .
CAUTION:
Only one adjusting shim can be selected.
a. Using height gauge, measure dimension “S
1 ” and “S2 ”.
b. Install selected 6th main adjusting shim to mainshaft.
17. Press in mainshaft rear bearing using the drifts.
18. Install mainshaft C-ring onto mainshaft, and check that end play
of mainshaft rear bearing satisfies the standard value.
If measurement is outside the standard range, reselect main-
shaft C-ring. Refer to MT-100, "
MAINSHAFT C-RING" . End play: 0 - 0.1 mm (0 - 0.004 in)
Dimension“S” = (S
1 - S2 ) - End play
S: Thickness of adjusting shim
S
1 : Dimension from mainshaft standard face to
mainshaft rear bearing press-fit end face
S
2 : Dimension from mainshaft standard face to
6th main gear end face
SCIA0995E
SCIA0978E
End play standard value : 0 - 0.06 mm (0 - 0.0024 in)
SCIA0979E
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MT-84
MAINSHAFT AND GEARS
19. Install C-ring holder, and then install a new snap ring.
CAUTION:
Do not reuse snap ring.
20. Check end play of 1st and 2nd main gears.
PCIB0805E
End play standard value
1st main gear : 0.20 - 0.30 mm (0.0079 - 0.0118 in)
2nd main gear : 0.06 - 0.16 mm (0.0024 - 0.0063 in)
SCIA0973E