Technical data

148
INSPECTING THE CUT-OFF
- Remove the SAS valve
- Connect the pump in vacuum position (VACUUM) to the
CUT - OFF valve vacuum inlet
- Apply a vacuum of over 0.5 BAR
- Check that this value is maintained over time
- If the value is not maintained, proceed to replace
- Using a «T» branch and rubber hoses, implement a parallel
connection between the rubber sleeve and the vacuum inlet
of the CUT - OFF valve
- Connect the branch to the ^SlQgWfSK, pump
- Set the pump in vacuum position (VACUUM)
- Using pliers with flat and long tips, temporarily clamp the
rubber hose in the proximity of the valve
- Command the pump to create a vacuum of over 0.5 BAR
- Release the hose and check the vacuum behaviour
- In normal operating conditions, the vacuum undergoes a
drop and then settles. Then there occurs a gradual and slow
depression up to the value of about 0.4 BAR. At this point,
the valve opens and vacuum suddenly resets. A seal failure
or opening at different vacuum values are abnormal. Pro-
ceed to the replacement.
N.B.
BESIDES IMPAIRING THE FUNCTIONALITY OF THE CUT - OFF,
AN INCORRECT SEAL OF THE CUT-OFF VALVE MEMBRANE
AFFECTS THE IDLE OPERATION.
N.B.
A SEAL FAILURE OF THE CUT - OFF VALVE CAUSES EXHAUST
NOISE (EXPLOSIONS IN THE SILENCER). A WRONG CALIBRA-
TION OF THE CUT
- OFF VALVE CAN IMPAIR THE CORRECT FUNCTIONALITY OF
THE CATALYTIC CONVERTER.
Specific tooling
020329Y Pump
INSPECTING THE CUT OFF