Pic. 3.55. Installing the gearbox on the mounting plate
Install the gearbox on the mounting plate (B.Vi.1581) (pic. 3.55).
Remove the clutch release cylinder.
Pic. 3.56. Bolts located inside the crankcase
Unscrew the bolts located inside the crankcase (pic. 3.56).
Pic. 3.57. Removing the rear cover
Remove the rear casing strictly along the horizontal axis of the box, as it includes a lubricant capsule located in the input shaft hole (pic. 3.57).
Pic. 3.58. Disabling first and fifth gears
Engage first gear with the shift lever, and fifth gear by sliding its fork along the stem (pic. 3.58).
Turn out a bolt of a secondary shaft and turn away a nut of an input shaft.
With the help of a core (B.Vi.31-01), knock out the fifth gear fork pin.
Pic. 3.59. Removing the 5th gear fork pin
Remove the fork and fifth gear clutch.
Remove the 5th gear hub using the tool (V.Vi.1170).
Pic. 3.60. Removing the hub
Install gear coupling tool (B.Vi.1170) into the fifth gear position by turning it so as to align the splines of the gear coupling and the hub, and remove the tool together with the hub (pic. 3.60).
Pic. 3.61. Removing the fixed fifth gear
Remove the fixed 5th gear using tools (V.Vi.22-01 and V.Vi.1000) (pic. 3.61).
Remove the outer crankcase bolts.
Pic. 3.62. Removing the speed sensor
Remove speed sensor B (for semi-automatic transmission JH1) (pic. 3.62).
Pic. 3.63. Holes C to be covered
It is recommended to put two magnets or block holes C in order not to lose the balls and springs for fixing the rods 1/2 and 3/4 (pic. 3.63).
Pic. 3.64. Removing the stem and reverse contactor
Remove reverse stem A and reverse contactor B (pic. 3.64).
Press on the shift rod with a force directed outward.
Disconnect and remove the box crankcase.
Pic. 3.65. Removing the shift fork stem «reverse/fifth gear»
Rotate the reverse axle assembly to the left and remove the shift fork stem «reverse/fifth gear» (pic. 3.65).
Pic. 3.66. Removal of assembly of an axis of transfer of a backing
Raise the input shaft slightly and remove the reverse gear axle assembly (pic. 3.66).
Disconnect the 3/4 yoke pins using the tool (B.Vi.949) and remove the 3/4 stem and yoke assembly.
Pic. 3.67. Removing the stem and yoke assembly 3/4, input and output shafts with stem and yoke 1/2
Simultaneously remove the input and output shaft assembly with the stem and yoke 1/2 (pic. 3.67).
Pic. 3.68. Removing the pins
Remove pins A and B (pic. 3.68).
Removing gears
Clamp the output shaft in a vise with jaws, and then remove all gears.
Pic. 3.69. Removing retaining rings
When removing and installing circlips, use circlip pliers on one side and pliers on the other (pic. 3.69).
Checking details
Gear and clutch teeth must not be excessively worn or serrated.
Also, make sure that the shaft surfaces and the inner surfaces of the gears do not show signs of friction or excessive wear.
It is recommended to mark the position of the gear couplings relative to the hubs.
Gear group installation
Install in the reverse order of removal.
Retaining rings must be systematically replaced.