Checking The One-Way Valve - VESPA GT 200 Workshop Manual

10.9.1

Checking the One-Way Valve

Remove the SAS valve.
-
Connect the mityvac vacuum pump to cut-off
-
valve vacuum inlet as shown in the figure.
- Set the pump onto vacuum mode.
Operate the pump until a vacuum pressure of
-
0.5 bar is reached.
Check that this value is maintained does not
-
decrease with time.
If the value is not maintained, proceed by
-
replacing the component.
Note: Besides impairing the functionality of the
cut-off, an incorrect seal of the cut-off valve
membrane affects the engine operation at idle.
- Using a «T»
implement a parallel connection between the
rubber sleeve and the vacuum inlet of the cut-off
valve.
Connect the branch to the mityvac pump, as
-
shown in the figure.
Set the pump in vacuum position.
-
- Using pliers with flat tips clamp the rubber hose
in the proximity of the valve.
- Operate the pump until a vacuum pressure of
over 0.5 bar is reached.
Release the hose and check the valve response.
-
branch and rubber hoses,
149