Sym GTS 250, Service Manual

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4. Fuel System
4-3
Trouble Diagnosis
Poor engine start
y No fuel in fuel tank
y Clogged fuel tube
y Too much fuel in cylinder
y No spark from spark plug(malfunction of ignition
system )
y Clogged air cleaner
y Malfunction of carburetor chock
y Malfunction of throttle operation
Stall after started
y
Malfunction of carburetor chock
y
Incorrect ignition timing
y
Malfunction of carburetor
y
Dirty engine oil
y
Air existing in intake system
y
Incorrect idle speed
Rough idle
y Malfunction of ignition system
y Incorrect idle speed
y Malfunction of carburetor
y Dirty fuel
Intermittently misfire as acceleration
y Malfunction of ignition system
Late ignition timing
y Malfunction of ignition system
y Malfunction of carburetor
Power insufficiency and fuel consuming
y Fuel system clogged
y Malfunction of ignition system
Mixture too lean
y Clogged fuel injector
y Vacuum piston stick and closed
y Malfunction of float valve
y Fuel level too low in float chamber
y Clogged fuel tank cap vent
y Clogged fuel filter
y Obstructed fuel pipe
y Clogged air vent hose
y Air existing in intake system
Mixture too rich
y
Clogged air injector
y
Malfunction of float valve
y
Fuel level too high in float chamber
y
Malfunction of carburetor chock
y
Dirty air cleaner
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