Primary shaft oil seal
1. Remove the gearbox as described in paragraph 6.
2. Remove the clutch release bearing as described in Chapter 6.
3. Loosen the mounting bolts and remove the cover plate from the inside of the gearbox bell housing (see fig. 4.3).
Fig. 4.3. Removing the cover plate from the gearbox housing
4. Carefully slide the cover plate over the input shaft and remove the shims (see fig. 4.4).
Fig. 4.4. Remove the adjusting shims
5. Use a screwdriver to pry the oil seal out of the plate housing (see fig. 4.5).
Fig. 4.5. Location of the primary shaft oil seal (shown by arrow) on the cover plate
6. Thoroughly clean the cuff seat in the cover.
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7. Hammer the new seal into place using a wrench or pipe until the seal rests on the lugs in the cover.
8. Hold the shims in place with a light coat of grease, then slide the cover into place on top of the input shaft.
9. Apply sealant to the threads of the cover plate mounting bolts, then install the bolts and tighten them to the specified torque.
10. Install the clutch release lever and bearing as described in Chapter 6.
11. Install the gearbox as described in paragraph 6.
Secondary shaft oil seal
Note: A new gearbox secondary shaft flange mounting nut will be required during installation.
12. Disconnect the propeller shaft from the secondary shaft flange of the gearbox, as described in Chapter 8.
13. Make sure the gearshift lever is in neutral position.
14. Install a holding device on the secondary shaft flange. You can use two metal strips and bolts - install the bolts in the holes in the flange and use the device to hold the flange. Note that the device should not block access to the flange nut.
15. Hold the flange from turning and unscrew the fastening nut. A new nut must be used for installation (see fig. 4.15).
Fig. 4.15. Unscrewing the secondary shaft flange fastening nut of the gearbox
16. Remove the flange from the shaft, using a puller if necessary.
17. Use a screwdriver to pry the oil seal out of the housing.
18. Clean the cuff body thoroughly.
19. Drive in the new seal using a pipe or a wrench until the outer surface of the seal is flush with the surface of the housing.
20. Install the flange on the secondary shaft and secure it with a new nut. Tighten the nut to the required torque.
21. Connect the propeller shaft to the secondary shaft flange as described in Chapter 8.