Excessive Oil Consumption/Exhaust Smoke; Insufficient Lubrication Pressure; Engine Tends To Cut-Off At Full Throttle - PIAGGIO MSS X9 EVOLUTION 250 Workshop Manual

Troubleshooting
Possible Cause
Automatic starter failure
Air filter blocked or dirty.
Faulty spark plug or incorrect ignition advance
The carburettor is dirty; fuel pump or vacuum valve damaged Remove, wash with solvent and dry with compressed air or re-
Battery flat
Intake coupling cracked or clamps incorrectly tightened
Defective floating valve
Carburettor nozzles clogged

Excessive oil consumption/Exhaust smoke

EXCESSIVE OIL CONSUMPTION/SMOKEY EXHAUST
Possible Cause
Worn valve guides
Worn valve oil guard
Oil leaks from the couplings or from the gaskets
Worn or broken piston rings or piston rings that have not been
fitted properly

Insufficient lubrication pressure

Possible Cause
By-Pass remains open
Oil pump with excessive clearance
Oil filter too dirty
Oil level too low

Engine tends to cut-off at full throttle

Possible Cause
Faulty fuel supply
Incorrect float level
Water in the carburettor
Maximum nozzle dirty - lean mixture
TROUBL - 48
connect the cap to the spark plug, and this in turn to the ground.
Check: mechanical movement, electric connection and fuel
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
Replace the spark plug or check the ignition circuit components
Check the charge of the battery, if there are any sulphur marks,
replace and use the new battery following the instructions
Replace the intake coupling and check the clamps are tight-
Check the proper sliding of the float and the functioning of the
Dismantle, wash with solvent and dry with compressed air
Check and replace the gaskets or restore the coupling seal
Replace the piston cylinder unit or just the piston rings
POOR LUBRICATION PRESSURE
Check the By-Pass and replace if required. Carefully clean the
Perform the dimensional checks on the oil pump components
Restore the level using the recommended oil type (Selenia HI
ENGINE STOP FULL THROTTLE
Check or replace the pump and the vacuum valve, check the
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
Wash the nozzle with solvent and dry with compressed air
MSS X9 Evolution 250
Operation
If the fuel tank is empty, refuel and start up.
supply, replace if required.
drip dry and then reassemble.
place
shown in the chapter
ened
valve
Operation
Check and replace the head unit if required
Replace the valve oil guard
Operation
By-Pass area.
Replace the cartridge filter
Scooter 4 Tech)
Operation
vacuum intake and the pipe sealing
the tank level with the carburettor inverted.
Empty the tank through the appropriate bleed nipple.