PIAGGIO MSS ZIP 100 4T, Service Manual

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Engine tends to cut-off at idle
THE ENGINE TENDS TO STOP AT IDLE SPEED
Possible Cause Operation
Wrong idling adjustment Correctly adjust the engine idling and check the level of the
C.O.
Spark plug defective or faulty Replace the spark plug with one with the specified degree and
check the plug gap
The starter remains activated Check that the automatic starter works and moves correctly
and it is properly powered.
Minimum jet dirty Remove the carburettor, wash with solvent and dry with com-
pressed air
Electronic ignition circuit failure Use a stroboscopic light and an rpm indicator to check for cor-
rect ignition advance and make sure the flywheel is correctly
keyed
Pressure too low at the end of compression Check the thermal group seals and replace worn components;
check and restore the correct valve clearance.
Incorrect timing Time the system and check the timing system components
Excessive exhaust noise
EXCESSIVE EXHAUST NOISE
Possible Cause Operation
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
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
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
Troubleshooting
MSS ZIP 100 4T
TROUBL - 42