Mainshaft and Gears
MAINSHAFT AND GEARSDisassembly and Assembly
GENERAL PRECAUTIONS
^ Do not reuse snap rings.
^ Position mainshaft on the vise with back plate and remove gears and snap rings.
^ For installation and removal of snap ring, position snap ring pliers and flat pliers at both sides of snap ring. Stretch snap ring, and move it with flat pliers.
^ Disassemble gear components putting matching marks on the parts that do not affect any functions.
DISASSEMBLY
1. Remove snap ring (1).
2. Install Tool (A) and suitable tool onto 6th main gear (1), and remove mainshaft rear bearing inner race (2) and 6th main gear (1) from mainshaft.
Tool number A: ST33052000 ( - )
3. Install Tool (A) and suitable tool onto 4th main gear (1), and remove 5th main gear (2), and 4th main gear (1) from mainshaft.
Tool number A: ST33052000 ( - )
4. Remove intermediate adjusting shim.
5. Install Tool (A) and suitable tool onto 1st main gear (1), and remove 1st main gear (1), 1st-2nd synchronizer assembly (2), 2nd main gear (3), bushing, and 3rd main gear (4) from main-shaft.
Tool number A: ST33052000 ( - )
6. Install Tool (A) and suitable tool onto mainshaft front bearing inner race (1), and remove mainshaft front bearing inner race (1) from mainshaft.
Tool number A: ST33052000 ( - )
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 excessive wear of contact surfaces of coupling sleeve, synchronizer hub, insert key.
^ 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.
Bearing
Check items below. If necessary, replace them with new ones.
CAUTION: When replacing tapered roller bearing, replace outer and inner races as a set.
^ Damage and rough rotation of bearing
CAUTION: Bearing preloading shim: after the intermediate adjusting shim and/or the 6th main gear, 5th main gear, and 4th main gear have been replaced, it is necessary to modify the bearing preload setting by changing the bearing preload shim.
^ Replacing the intermediate adjusting shim.
- Increase the size of the bearing preload shim, if the replaced intermediate adjusting shim is thinner than the shim used before.
- Decrease the size of the bearing preload shim, if the replaced intermediate adjusting shim is thicker than the shim used before.
^ Replacing the 6th main gear, 5th main gear, and 4th main gear.
- Measure the thickness of the main gear used before and the new main gear.
- Increase the thickness of the bearing preload shim, if the difference is smaller than 0.025 mm (0.0010 in).
- Decrease the thickness of the bearing preload shim, if the difference is greater than 0.025 mm (0.0010 in).
ASSEMBLY
1. Press-fit the mainshaft front bearing inner race (1) onto the mainshaft using Tool (A).
Tool number A: ST36720030 ( - )
2. Install 1st main gear (1), and 1st-2nd synchronizer assembly (2) onto the mainshaft.
3. Press-fit the bushing (3) onto the mainshaft using Tool (A).
Tool number A: KV32102700 ( - )
4. Press-fit 3rd main gear (1) onto the mainshaft with Tool (A) after installing the 2nd main gear (2) and the 3rd main gear (1) onto the mainshaft.
Tool number A: KV32102700 ( - )
5. Select the thickness of the intermediate adjusting shim (1) needed by measuring the distance "L" between the base of the mainshaft (2) and the top of the 3rd main gear (3). Refer to the table to determine the thickness of the adjusting shim.
6. Install selected intermediate adjusting shim.
7. Press-fit the 4th main gear (1) onto the mainshaft using Tool (A).
Tool number A: KV32102700 ( - )
8. Press-fit the 5th main gear (1) onto the mainshaft using Tool (A).
Tool number A: KV32102700 ( - )
9. Press-fit the 6th main gear (1) onto the mainshaft using Tool (A).
Tool number A: KV32102700 ( - )
10. Press-fit the mainshaft rear bearing inner race (1) onto the main-shaft using Tool (A).
Tool number A: ST30901000 (J-26010-01)
11. Install snap ring onto mainshaft.