PIAGGIO Vespa LX 150 4T Euro 3 Service Station Manual page 46

Troubleshooting
Engine tends to cut-off at full throttle
THE MOTOR TENDS TO STOP AT MAXIMUM THROTTLE
Possible Cause
Maximum jet clogged
Water or condensate in the carburettor tank
Level in tank too low
Engine tends to cut-off at idle
Possible Cause
Incorrect idle adjustment
Incorrect timing
The starter remains on
Faulty spark plug or incorrect ignition advance
Pressure too low at the end of compression
Minimum nozzle dirty
High fuel consumption
Possible Cause
Air filter blocked or dirty.
Inefficient Starter
Loose nozzles
Incorrect float level
Transmission and brakes
TROUBL - 4
THE ENGINE TENDS TO STOP AT IDLE SPEED
EXCESSIVE FUEL CONSUMPTION
Vespa LX 125 - 150 4T Euro 3
Operation
Remove the carburettor, wash with solvent and dry
with compressed air
Remove the tank, wash with solvent and dry with
compressed air
Restore the level in the tank by bending on the float
the thrusting reed of the petrol inlet rod so as to
have the float parallel to the tank level with the
carburettor inverted.
Operation
Adjust using the rpm indicator
Time the system and check the timing system
components
Check: electric wiring, circuit not interrupted, me-
chanical movement and power supply; replace if
necessary
Replace the spark plug or check the ignition circuit
components
Check the thermal group seals and replace worn
components
Wash the nozzle with solvent and dry with com-
pressed air
Operation
Clean according to the procedure
Check: electric wiring, circuit continuity, mechani-
cal sliding and power supply
Check the maximum and minimum nozzles are
adequately fixed in their fittings
Restore the level in the tank by bending on the float
the thrusting reed of the petrol inlet rod so as to
have the float parallel to the tank level with the
carburettor inverted.