Removal shafts
On 5-speed gearboxes
Remove the rear cover of the gearbox housing.
Loosen the nut at the end of the secondary shaft.
On a 5-speed gearbox type "F"
Remove the thrust washer from the secondary shaft.
Knock out the 5th gear shift fork locking pin.
Remove the 5th gear shift fork assembly with the 5th gear synchronizer.
Remove the 5th gear.
Remove the 5th gear needle bearing.
Remove the nut from the input shaft.
Remove the 5th gear from the input shaft.
On a 5-speed gearbox type "G"
Remove the nut from the input shaft.
Remove the reverse gears from the input and output shafts.
Knock out the locking pin of the 5th gear and reverse gear engagement fork.
Remove the 5th gear and reverse gear engagement fork together with the 5th gear and reverse gear synchronizer.
Remove the V-gear driven gear and needle bearing from the secondary shaft.
Remove the V-gear pinion from the input shaft.
On gearboxes of types "F" and "G"
Unscrew the stopper 1 of the reverse gear lock and the locking bolt 3 of the reverse gear engagement lever.
On type "F" gearboxes, remove the bolt, spring and ball from the reverse gear fork rod retainer.
Loosen the bolts securing the gearbox housing to the clutch housing.
Remove the gearbox housing.
Remove the magnet from the gearbox housing.
Remove the axle and reverse idler gear.
On 5-speed gearboxes, unscrew the locking bolt of the 5th gear and reverse gear fork slider. Remove the 5th gear and reverse gear fork slider and fork.
On type "F" gearboxes
Set the gearbox shafts to neutral position, set the gear shift fork rod lock and the movable leash as shown in the figure.
Move the gear selector rod so as to turn the gear selector fork rod of I and II, III and IV gears counterclockwise.
While holding the I and II, III and IV gear shift fork rod in the turned position, push the gear selection rod into the crankcase to lift the I and II, III and IV gear shift fork rod.
Without changing the position of the parts, remove the leash split pin.
Remove the primary and secondary shafts together, remove the rod with the shift forks for I and II, III and IV gears.
Remove the differential.
Remove the shift fork linkage and take out the detent ball and spring.
On the gearbox type "G"
Knock out the pin from the reverse intermediate lever.
Remove the intermediate reverse gear lever shaft and the lever itself by moving the gear shift shaft.
Align the ends of the fork rod locks of the first and second, third and fourth gears and the leash.
Turn the shift fork rod of I and II, III and IV gears clockwise.
Raise the shift forks of I and II, III and IV gears as much as possible.
Lift the leash, remove the ball and the retainer spring.
Remove the rod and forks for shifting I and II, III and IV gears.
Remove the primary and secondary shafts together.
Remove the differential.
On gearboxes of types "F" and "G"
Remove the seal from the primary shaft. Press the outer ring of the front bearing of the primary shaft out of the clutch housing socket using a mandrel, applying force from the side of the shaft.
Pull and remove the sleeve from the secondary shaft. Press the outer ring of the secondary shaft front bearing out of the clutch housing socket.
Using a mandrel, press out the outer rings of the differential bearings from the sockets of the gearbox housing and clutch housing.
Press out the differential bearing seals if they need to be replaced.
Press the outer rings of the rear bearings of the primary and secondary shafts out of the crankcase using a bronze drift, which should be installed in the grooves of the bearing seats.