Remove the gearshift mechanism cover (section 10.2.2).
Remove the front and rear gearbox covers (section 10.2.3 or 10.2.4).
Remove the reverse gear pinions (section 10.2.5).
Remove the gear shift forks.
Knock out pin (3) on the reverse gear fork rod from the lever (1) and move the lever as far forward as possible (see fig. 183).
Fig. 183. Removing the rod with the reverse gear engagement fork.
1 - reverse gear engagement lever,
2 - rod with fork for engaging reverse gear,
3 - pin.
Remove the rod with the fork from the gearbox housing and at the same time remove the leash.
Using a socket wrench, loosen the intermediate shaft mounting nut and unscrew it (see fig. 184). To prevent the shaft from rotating, engage two gears simultaneously.
Fig. 184. Unscrewing the intermediate shaft nut.
Loosen the bearing cover mounting bolts (1) and remove the cover together with the adjusting ring (see fig. 185).
Fig. 185. Removing the bearing cover (1) in the gearbox.
Remove the bearings with locking grooves from the front and rear ends of the intermediate shaft using a puller, as shown in Fig. 186.
Fig. 186. Removing the front bearing of the intermediate shaft.
Remove the bearing with the locking groove from the rear end of the driven shaft.
Place a technological sleeve on the rear end of the driven shaft, which prevents the first gear from moving, and tighten the flange fastening nut.
Move the driven shaft back in the gearbox housing and remove the drive shaft assembly forward. Pay attention to the position of the fourth gear synchronizer on the free end of the drive shaft and the needle bearing of the front support of the drive shaft.
Set the third and fourth gear engagement clutch (1) to the third gear engagement position. Move the driven shaft all the way back and remove it from the gearbox housing at an angle upwards (see fig. 187).
Fig. 187. Removing the driven shaft.
Similarly, remove the intermediate shaft from the crankcase.
To install the gear, perform the following work:
Install the intermediate shaft into the gearbox housing.
Place the process sleeve on the rear end of the driven shaft and secure it with the flange mounting nut.
Place the third and fourth gear engagement clutch in the third gear engagement position.
Tilt the driven shaft back and install it in the crankcase.
Insert the needle bearing into the drive shaft.
Place the fourth gear synchronizer ring on the cone of the drive shaft gear.
Install the drive shaft assembly from the front into the gearbox housing, raising the front end of the driven shaft so that its journal fits into the drive shaft needle bearing without tension.
Remove the process sleeve from the rear end of the driven shaft.
Place the bearings with the locking groove on the front and rear ends of the intermediate shaft using a mandrel or light hammer blows. To facilitate the installation of the bearings, lift the intermediate shaft.
Engage two gears simultaneously and lock the rotation of the intermediate shaft.
Install the front intermediate shaft mounting nut, tighten and lock.
Adjust the axial clearance of the driven shaft within 0...0.05 mm, preferably 0. To do this, use a depth gauge to measure the depth of the groove in the bearing cover and the distance from the end of the mounting ring on the outer ring of the bearing to the split surface of the gearbox housing.
Fig. 188. Measuring the axial clearance of the driven shaft.
Install the selected adjusting ring into the bearing cap, place the cap on the bearing and secure.
Set the gear to reverse.
Install and secure the rear gearbox cover.
Adjust the axial clearance of the drive shaft within 0...0.05 mm, preferably 0. To do this, use a depth gauge to measure the depth of the groove in the front cover of the gearbox with the gasket and the distance between the end face of the mounting ring on the outer ring of the drive shaft bearing and the split surface of the gearbox housing (see fig. 189). Spare parts come with adjusting rings with a thickness of 0.1; 0.2 and 0.3 mm.
Fig. 189. Measuring the axial clearance of the drive shaft.
Adjust the axial clearance of the intermediate shaft within 0.07...0.15 mm. To do this, use a depth gauge to measure the depth of the groove in the front cover of the gearbox with the gasket and the distance between the end face of the mounting ring on the outer ring of the intermediate shaft bearing and the split surface of the gearbox housing (see fig. 190), when measuring the intermediate shaft must be pressed against the rear cover of the gearbox. Install the selected adjusting ring in the front cover of the gearbox, place the cover on the gearbox housing, tighten and secure the mounting bolts.
Fig. 190. Measuring the axial clearance of the intermediate shaft.
1 - cover,
2- adjustment ring.
Install the gear shift cover.
Install the clutch housing.