PIAGGIO MSS X9 EVOLUTION 250, Workshop Manual

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Engine tends to cut-off at idle
ENGINE STOP IDLING
Possible Cause Operation
Incorrect timing Time the system and check the timing system components
Cut off device failure Check that the following parts work properly: valve; diaphragm;
spring; and that the air calibration elements are clean; check if
the sponge filter is clean too
Incorrect idle adjustment Adjust using the rpm indicator
Pressure too low at the end of compression Check the thermal group seals and replace worn components
Faulty spark plug or incorrect ignition advance Replace the spark plug or check the ignition circuit components
The starter remains on Check: electric wiring, circuit not interrupted, mechanical
movement and power supply; replace if necessary
Minimum nozzle dirty Wash the nozzle with solvent and dry with compressed air
Excessive exhaust noise
EXCESSIVE EXHAUST NOISE
Possible Cause Operation
Secondary air device cut-off valve not working Replace the secondary air device
Depression intake pipe of the secondary air device disconnec-
ted or dented
Replace the pipe
Reed valve of the secondary air device does not close correctly
and wears out the rubber coupling between the device and the
head pipe
Replace the device and the coupling
High fuel consumption
HIGH FUEL CONSUMPTION
Possible Cause Operation
Float level Restore the level in the tank by bending on the float the thrust-
ing reed of the petrol inlet rod so as to have the float parallel to
the tank level with the carburettor inverted.
Loose nozzles Check the maximum and minimum nozzles are adequately
fixed in their fittings
Fuel pump failure Check that there is no fuel in the low-pressure duct
Starter inefficient Check: electric wiring, circuit continuity, mechanical sliding and
power supply
Air filter blocked or dirty. Dismantle the sponge, wash with water and shampoo, then
soak it in a mixture of 50% petrol and 50% of specific oil (Se-
lenia Air Filter Oil), then hand dry without squeezing, allow to
drip dry and then reassemble.
SAS malfunctions
A
NOMALIES IN THE SECONDARY AIR DEVICE
Possible Cause Operation
Secondary air device cut-off valve not working Replace the secondary air device
Depression intake pipe of the secondary air device disconnec-
ted or dented
Replace the pipe
Reed valve of the secondary air device does not close correctly
and wears out the rubber coupling between the device and the
head pipe
Replace the device and the coupling
MSS X9 Evolution 250
Troubleshooting
TROUBL - 49