Loosen the mounting bolt and remove the reverse gear engagement lever ("2" in Fig. 171).
Fig. 171. Gear shift mechanism cover with shift levers.
1 - 3/4 gear release lever,
2 - reverse gear engagement lever,
3 - 1/2 gear engagement lever,
4 - gear shift mechanism cover.
Remove the installation ring from the reverse gear engagement shaft.
Loosen the gearshift mechanism cover mounting bolts.
Carefully remove the cover from the mounting pins and at the same time use hammer blows to move the reverse gear engagement shaft toward the crankcase, move the cover away from the split surface of the crankcase to a distance at which you can insert the palm of your hand into the gap (see fig. 172 and 173).
Fig. 172. Reverse gear engagement shaft.
1 - mounting pin,
2 - reverse gear engagement shaft.
Fig. 173. Removing the gearshift mechanism cover.
1 - 3/4 gear engagement rod,
2 - 3/4 gear engagement fork,
3 - 1/2 gear engagement fork,
4 - 1/2 gear engagement rod.
Remove forks 2 and 3 from the engagement rods in the direction indicated by the arrows in Fig. 173.
Tilt the cover of the switching mechanism downwards, then lift it upwards.
When installing the gearshift mechanism cover, perform the following operations:
Using grease, glue a new gasket onto the thoroughly cleaned split surface of the gearbox housing.
Place the reverse gear fork rod leash in the middle position.
Install the cover of the engagement mechanism so that the pin of the reverse gear engagement shaft enters the groove of the leash.
Press the cover against the crankcase so that the forks are simultaneously placed on the corresponding gear engagement rods.
Using light hammer blows, seat the cover on the split surface of the gearbox housing. Pay attention to the correct seating of the cover on the mounting pins. Pull the reverse gear engagement shaft out of the cover.
Tighten the mounting bolts evenly in a crosswise pattern.
To correctly install the gearshift mechanism cover, it is necessary to move the shaft and the reverse gear engagement pin relative to the cover ("3" in Fig. 174) so that a certain distance is maintained between the pin and the split surface of the cover (distance "b" in Fig. 174).
Fig. 174. Adjusting the position of the reverse gear engagement finger.
a=10 mm, the distance between the detachable surface and the finger after installing the cover.
in= 25 mm, distance between the detachable surface and the finger before installing the cover,
1 - gear shift mechanism cover,
2 - reverse gear engagement lever,
3 - finger with reverse gear engagement shaft.
Place a washer on the reverse gear engagement shaft.
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Install the installation ring into the groove on the reverse gear engagement shaft.
Install the reverse gear engagement lever onto the shaft splines and tighten the lever mounting bolt.
Check the operation of the mechanism by sequentially engaging all gears.
Fill the gearbox with oil.