PIAGGIO 633929(IT), Руководство по обслуживанию станции, Страница: 56 / 314

Possible Cause Operation
Oil level too low Restore the level using the recommended oil type
(Selenia HI Scooter 4 Tech)
Engine tends to cut-off at full throttle
ENGINE STOP FULL THROTTLE
Possible Cause Operation
Faulty fuel supply Check or replace the pump and the vacuum valve,
check the vacuum intake and the pipe sealing
Incorrect float level 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.
Water in the carburettor Empty the tank through the appropriate bleed nip-
ple.
Maximum nozzle dirty - lean mixture Wash the nozzle with solvent and dry with com-
pressed air
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 calibra-
tion 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, me-
chanical movement and power supply; replace if
necessary
Minimum nozzle dirty Wash the nozzle with solvent and dry with com-
pressed 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
disconnected 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
MP3 125
TROUBL - 4