VESPA ET4 50, Workshop Manual

Page: 67 / 185

Removing the driving pulley
- Lock the driving pulley using the appropriate tool.
- Remove the central nut with the related washer,
then remove the drive and the plastic fan.
- Remove the stationary half-pulley.
- Remove the belt, washer and remove the mobile half-pulley with its bushing, being careful that the
rollers and contrast plate fitted loosely on it do not come off.
Specific tooling
020451Y Starting ring gear lock
Inspecting the rollers case
1) Check that the bushing and the sliding rings of
the mobile pulley do not show signs of scoring or
deformation.
2) Check the roller running tracks on the contact
pulley; there must not be signs of wear and check
the condition of the contact surface of the belt on
the half-pulleys (mobile and stationary).
3) Check that the rollers do not show signs of
marked facetting on the sliding surface and that
the metallic insert does not come out of the plastic
shell borders.
4) Check the integrity of the sliding blocks of the
contact plate.
- Check that the internal bushing shown in the fig-
ure is not abnormally worn and measure inside
diameter « A ».
- Measure outside diameter « B » of the pulley slid-
ing bushing shown in the figure.
CAUTION
DO NOT LUBRICATE OR CLEAN THE BUSHING.
Characteristic
Driving pulley / Maximum diameter:
ET4 50
Engine
ENG - 67