VESPA GTV 125, Руководство по обслуживанию станции

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Possible Cause Operation
Oil pump with excessive clearance Perform the dimensional checks on the oil pump
components
Oil filter too dirty Replace the cartridge filter
Oil level too low Restore the level adding the recommended oil
type
Engine tends to cut-off at full throttle
THE MOTOR TENDS TO STOP AT MAXIMUM THROTTLE
Possible Cause Operation
Level in tank too low 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.
Tank breather hole obstructed Restore the proper tank aeration
Fuel supply pipes choked or clogged Restore the adequate fuel supply
Maximum nozzle dirty - lean mixture Wash the nozzle with solvent and dry with com-
pressed air
Water in the carburettor Empty the tank through the appropriate bleed nip-
ple.
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.
Faulty fuel supply Check or replace the fuel pump, and check the
vacuum intake and the pipe sealing
Engine tends to cut-off at idle
THE ENGINE TENDS TO STOP AT IDLE SPEED
Possible Cause Operation
Air calibrated holes in carburettor blocked Dismantle, wash with solvent and dry with com-
pressed air
Defective floating valve Check the proper sliding of the float and the func-
tioning of the valve
Level in chamber too high Restore the level of the float chamber bending on
the float the thrusting reed of the petrol inlet pin so
as to have the float parallel to the float chamber
level, with the carburettor inverted.
The starter remains on Check the electric connection, fuel supply and me-
chanical movement. Replace if required.
Air filter blocked or dirty Remove the sponge, wash with water and car
shampoo, then soak it in a mixture of 50% petrol
and 50% specific oil. Press with your hand without
squeezing, allow it to drip dry and refit.
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
Troubleshooting
Vespa GTV 125
TROUBL - 4