Contents: Disassembly ↓ Assembly ↓
Removal the flange of the elastic coupling with the puller A.40005/3/9B/9C
1 – elastic coupling flange; 2 – bolts for fastening the device to the flange; 3 – strip 9C of puller A.40005/3; 4 – puller A.40005/3
Internal view of the clutch housing
The red arrows indicate the nuts that secure the clutch housing to the gearbox.
The white arrow indicates the hole in the front cover for releasing oil from the gearbox housing to prevent the clutch discs from becoming oily.
Internal view of the rear cover of the gearbox
1 – screw with eye for fastening the return spring of the gear shift lever; 2 – lever release spring; 3 – gear shift lever; 4 – screw for limiting the transverse travel of the lever.
The arrow indicates the direction in which the lever must be moved to disengage it from the gearshift rod heads and remove the rear gearbox cover.
Primary shaft parts
1 – retaining ring; 2 – spring washer; 3 – bearing; 4 – primary shaft; 5 – synchronizer spring; 6 – synchronizer locking ring; 7 – retaining ring; 8 – bearing
Secondary shaft parts
1 – retaining ring; 2 – spring washer; 3 – synchronizer hub; 4 – synchronizer clutch; 5 – retaining ring; 6 – synchronizer locking ring; 7 – synchronizer spring; 8 – washer; 9 – gear of the 3rd gear; 10 – secondary shaft; 11 – 2nd gear pinion; 12 – washer; 13 – synchronizer spring; 14 – blocking ring; 15 – retaining ring; 16 – synchronizer hub; 17 – synchronizer clutch; 18 – retaining ring; 19 – synchronizer locking ring; 20 – synchronizer spring; 21 – washer; 22 – 1st gear pinion; 23 – 1st gear bushing; 24 – bearing; 25 – reverse gear; 26 – spring washer; 27 – retaining ring; 28 – speedometer drive gear; 29 – rear bearing; 30 – oil seal; 31 – elastic coupling flange; 32 – nut; 33 – seal; 34 – centering ring; 35 – retaining ring
Gear Shift Lever Parts
1 – bolt of the tension spring; 2 – washer; 3 – release spring; 4 – gasket; 5 – guide cup; 6 – gasket; 7 – washer; 8 – limit bolt; 9 – gear shift lever; 10 – ball joint; 11 – spherical washer; 12 – spring; 13 – support washer; 14 – retaining ring; 15 – gasket; 16 – flange; 17 – spring washer; 18 – nut; 19 – cuff; 20 – inner cover; 21 – lever rod; 22 – cap; 23 – thrust cushion; 24 – elastic bushing; 25 – spacer sleeve; 26 – elastic bushing; 27 – locking sleeve
Disassembly
1. Wash the gearbox and install it on the stand.
2. Drain the oil and remove the bottom cover with gasket.
3. Remove the clutch release fork and, from the guide sleeve of the front gearbox cover, the clutch assembly with the bearing and connecting spring.
4. Remove the clutch housing with the gasket and the front cover of the gearbox, together with the oil seal and spring washer (see fig. Internal view of the clutch housing).
5. Remove the speedometer drive with the gasket and the reverse light switch, being careful not to deform its housing.
6. Remove the bolt securing the shift fork for III and IV gears.
7. Install the 41.7816.4068 locking pin on the primary shaft or engage two gears simultaneously. This will prevent the primary, secondary and intermediate shafts from turning and will allow subsequent disassembly operations to be performed.
8. Remove the retaining ring from the end of the transmission secondary shaft.
9. After straightening the lock washer, unscrew the nut a few turns to move the centering ring of the flexible coupling, and tighten the nut again.
10. Using the A.40006/1 ejector and the A.40005/4 puller, remove the centering ring of the flexible coupling of the cardan shaft from the end of the secondary shaft.
11. Remove the seal of the centering ring of the elastic coupling from the end of the secondary shaft, unscrew the nut and remove the flange of the elastic coupling using the A.4005/3/9B/9C puller (see fig. Removing the elastic coupling flange with puller A.40005/3/9B/9C).
12. Remove the rear cover of the gearbox by unscrewing its mounting nuts and screw 4 (see Fig. Internal view of the rear cover of the gearbox) limiting the lateral travel of the lever, and also moving the gear shift lever to the left to release it from the gear engagement rods.
13. Remove the rear bearing from the secondary shaft. Remove the speedometer drive pinion.
14. Remove the fork with the spacer sleeve from the reverse gear engagement rod and the reverse gear intermediate gear from the axle.
15. Remove the reverse drive pinion retaining ring from the intermediate shaft; remove the gear and spring washer.
16. Remove the reverse driven gear retaining ring from the secondary shaft, using the 41.7816.4069 drift to press the spring washer to relieve the load on the retaining ring.
17. Remove the reverse driven gear and spring washer.
18. Using shaped mandrels (type of screwdrivers) and rod punches, remove the front and rear bearings of the intermediate shaft from the gearbox housing. On the inner rings of the double-row front bearing, apply marks according to which these rings are installed in their previous places in the outer ring of the bearing.
19. Remove the intermediate shaft from the gearbox housing by tilting it as shown in the figure.
20. Remove cover 20 (see Fig. Gear shift drive) rod retainers together with the gasket, remove the springs and balls of the retainers. Remove rod 18 of the reverse gear, rod 17 of the fork of switching the III and IV gears from the gearbox housing.
21. Unscrew the bolt securing the 1st and 2nd gear forks, remove the rod and forks.
22. When removing the rods, simultaneously remove the three locking crackers 19.
23. Remove the secondary shaft intermediate bearing retaining plate and the reverse intermediate gear shaft. The arrow shows the direction of the impact stroke of the screwdriver sleeve; use a hammer.
24. Using mandrels (type of screwdrivers) remove the input shaft together with the bearing and synchronizer ring and remove the needle bearing from the front end of the output shaft.
25. Knock the secondary shaft out of the intermediate bearing, remove the intermediate bearing and, tilting it as shown in the figure, remove the secondary shaft from the crankcase complete with gears, clutches and synchronizer rings.
26. Remove the synchronizer clutch of III and IV gears from the shaft.
27. Disassemble the primary shaft (see fig. Primary shaft parts). To do this, remove the retaining ring 7, the blocking ring 6 and the synchronizer spring 5.
28. Place the shaft on the press and, using mandrel 41.7816.4069, compress spring washer 2, remove retaining ring 1, then spring washer and bearing 3.
29. Disassemble the secondary shaft (see fig. Secondary shaft parts). To do this, remove gear 22 with sleeve 23, hub 16 with sliding clutch for switching 1st and 2nd gears, gear 11 of 2nd gear together with locking ring 14 of the synchronizer from the rear side of the shaft.
30. Install the secondary shaft with mandrel 41.7816.4069 (1) on the press, place support half rings (3) under the 3rd gear pinion, and, pressing the mandrel on the spring washer, remove the retaining ring (2), then the spring washer (4), the hub of the sliding clutch for switching 3rd and 4th gears and the 3rd gear pinion (5 – press rod).
31. Disassemble the gear shift lever and the rear cover, remove the cover 20 (see fig. Gear shift lever parts) lever, then retaining ring 14, washer 13, spring 12 and spherical washer 11.
32. Disconnect the release spring 3 of the lever from the eye of the bolt 1.
33. Remove the cuff 19, unscrew the flange mounting nuts 16 and remove the lever together with the flange, support 10 and cup 5.
Assembly
1. The gearbox is assembled in the reverse order of disassembly.
2. Please note that spring 22 (see Fig. Gear shift drive) the ball of the reverse fork rod retainer differs from others in its elasticity, it is painted green or has a cadmium coating.
3. When installing the clutch housing with the front cover of the gearbox, the hole in the front cover must be positioned as shown in the figure Internal view of the clutch housing.
4. Before installation, cover the working surface of the seals with LITOL-24 grease.
5. When assembling the secondary and intermediate shafts, use mandrels 41.7853.4028, 41.7853.4032, 41.7853.4039.
6. When installing the reverse gear retaining ring, use the 41.7816.4069 (2) tool as shown in the figure (1 – retaining ring, 3 – spring washer, 4 – secondary shaft reverse gear).