Mainshaft Disassembly
Mainshaft DisassemblyComponent Identification: Main Drive Gear and Mainshaft
Gear Inspections
Measure all mainshaft gear thrust clearances:
You can use either:
- A dial indicator
Or
- Feeler gauges
- Between Reverse and 4th
- Between 3rd and 2nd
- Between 1st and the mainshaft rear bearing
- Record any parts that need replacement on the Repair Order
Mainshaft Gear Radial Clearance Inspection
- Place the Mainshaft in a vice with jaw protectors
- Use a dial indicator
- Excess clearance indicates a bearing, shaft or gear problem
- Record any parts that need replacement on the Repair Order
Combine Step 1 thru 3
1. Remove the Main Drive Gear
2. Remove the Synchronizer Ring
3. Remove the Needle Bearing
Optional Step: Only required to replace the Main Drive Gear or the Main Drive Gear Bearing
4. Remove the Main Drive Gear Bearing selective Snap-Ring
- Use 2- equal length flat blade screwdrivers
- Measure the Snap-Ring thickness
- Record the measurement on the Snap-Ring sheet
- Place the Snap-Ring On the Selective Snap- Ring sheet (see of the Introduction)
Optional Step: to replace the Main Drive Gear Bearing or the Main Drive Gear
5. Remove the Bearing with SST 49- G030-370
6. The Main Drive Gear is bare
7. Remove the Mainshaft 6th gear selective Snap- Ring
- Use 2- equal length flat blade screwdrivers
- Measure the Snap-Ring
- Write the measurement on the Selective Snap- Ring sheet (see of the Introduction)
- Place the Snap-Ring on the Selective Snap- Ring sheet (see of the Introduction)
Combine Step 8 thru 12
8. Shift the 1st/2nd shift sleeve to the neutral position (centered between 1st and 2nd)
- Use SST 49-N017-101 to press off the 1st and 6th gear at the same time
- Caution: the Steel Index Ball {part #16} may come out during this operation, and the clutch hub could come apart releasing its 3-balls, 3-keys, and 3- springs
- Don't let the shaft fall
9. 6th Gear
10. Bearing
11. Inner Race
12. Needle Bearing
Combine Step 13 thru 15
13. Synchronizer Ring
14. Middle Ring
15. Inner Ring
16. Steel Index Ball (The index ball for the Inner Race May have come out in Step #11)
- Place the Steel Index Ball into the bag marked Springs and Steel Detent Balls
The Inner Race and Index Ball
17. Use SST 49-N017-101
- Press off the 1st/2nd Clutch Hub and 2nd gear at the same time
- Don't let the shaft fall
18. Place the 1st/2nd Clutch Hub in the clear plastic bag marked 1st/2nd
19. Remove the Synchronizer Rings
20. Middle Ring
21. Inner Ring
22. Remove 2nd Gear Needle Bearing
23. Remove the Selective Snap-Ring (Reverse)
- Use 2- equal length flat blade screwdrivers
- Measure the Snap-Ring thickness
- Record the measurement on the Selective Snap-Ring sheet
- Place the Snap-Ring Onto the Selective Snap-Ring Sheet (see of the Introduction)
24. Use SST 49-N017-101
- Remove the 5th/Reverse Clutch Hub and Reverse Gear at the same time
- Don't let the shaft fall
25. Place the 5th/Reverse Clutch Hub into the bag marked 5th / Reverse
26. Remove the Reverse Synchronizer Ring
27. Remove the Reverse Needle Bearing
28. The Mainshaft is bare
Combine Step 29 to 32
- Get the 1st/2nd Clutch Hub Bag
- Get the 5th / Reverse Clutch Hub Bag
Perform step 29 thru 30 on both clutch hubs
29. Remove the sleeve from the hub while it is in the bag
30. Make sure you have 3-Steel Balls and 3-Synchronizer Springs
31. Make sure you have 3-Synchronizer Keys
32. The Clutch Hub is bare
Synchronizer Ring Clearance Inspection
- Use feeler gauges
- If any synchronizer ring is not at specifications, replace the synchronizer ring
5th Synchronizer Inspection
Mainshaft Runout Inspection
- Use V-blocks and
- a dial indicator
- Write down any parts that need replacement on the repair order