Fig. 3.55. Installing the gearbox on the mounting plate
Install the gearbox on the mounting plate (B.Vi.1581) (Fig. 3.55).
Remove the clutch release slave cylinder.
Fig. 3.56. Bolts located inside the crankcase
Unscrew the bolts located inside the crankcase (Fig. 3.56).
Fig. 3.57. Removing the rear casing
Remove the rear casing strictly along the horizontal axis of the box, as it includes a capsule with grease located in the hole of the primary shaft (Fig. 3.57).
Fig. 3.58. Disengaging first and fifth gears
Engage first gear with the gear shift lever, and fifth gear by sliding its fork along the rod (Fig. 3.58).
Remove the secondary shaft bolt and the primary shaft nut.
Using a core (B.Vi.31-01), knock out the fifth gear fork pin.
Fig. 3.59. Removing the fifth gear fork pin
Remove the fifth gear fork and clutch.
Remove the fifth gear hub using the tool (B.Vi.1170).
Fig. 3.60. Removing the hub
Set the toothed clutch of the device (B.Vi.1170) to the position of the engaged fifth gear, turning it so as to align the splines of the toothed clutch and the hub, and remove the device together with the hub (Fig. 3.60).
Fig. 3.61. Removing the fixed fifth gear pinion
Remove the fixed fifth gear pinion using tools (B.Vi.22-01 and B.Vi.1000) (Fig. 3.61).
Remove the outer transmission case bolts.
Fig. 3.62. Removing the speed sensor
Remove the speed sensor B (for semi-automatic gearbox JH1) (Fig. 3.62).
Fig. 3.63. Openings C that need to be covered
It is recommended to install two magnets or cover holes C in order not to lose the balls and springs that fix the 1/2 and 3/4 rods (Fig. 3.63).
Fig. 3.64. Removing the rod and reverse contactor
Remove the reverse rod A and the reverse contactor B (Fig. 3.64).
Press the shift rod outward.
Disconnect and remove the gearbox housing.
Fig. 3.65. Removing the shift fork rod "reverse/fifth gear "
Turn the reverse gear shaft assembly to the left and remove the reverse/fifth gear shift fork rod (Fig. 3.65).
Fig. 3.66. Removing the reverse gear axle assembly
Slightly lift the input shaft and remove the reverse gear axle assembly (Fig. 3.66).
Disconnect the 3/4 fork pins using the tool (B.Vi.949) and remove the 3/4 fork and stem assembly.
Fig. 3.67. Removing the assembly of the rod and fork 3/4, the primary and secondary shafts with the rod and fork 1/2
At the same time, remove the primary and secondary shaft assembly with the rod and fork 1/2 (Fig. 3.67).
Fig. 3.68. Removing the locking pins
Remove locking pins A and B (Fig. 3.68).
Removal gears
Clamp the secondary shaft in a vice with jaws, then remove all gears.
Fig. 3.69. Removing the retaining rings
When removing and installing snap rings, use snap ring pliers on one end and flat-nose pliers on the other (Fig. 3.69).
Checking the details
The teeth of gears and couplings should not be too worn or have nicks.
Also, make sure that there are no signs of friction or excessive wear on the shaft surfaces and the inner surfaces of the gears.
It is recommended to mark the position of the gear couplings relative to the hubs.
Installing a group of gears
Perform installation in the reverse order of removal.
The retaining rings must be replaced regularly.