Troubleshooting - KYMCO FILLY LX 50 Service Manual

5
. FUEL SYSTEM

TROUBLESHOOTING

Engine is hard to start
• No spark at plug ( Section 15)
• Compression too low
• No fuel to carburetor
−Clogged fuel filter
−Restricted fuel line
−Faulty float valve
−Incorrectly adjusted float level
• Engine flooded with fuel
−Clogged air cleaner
−Fuel overflowing
• Intake air leak
• Contaminated fuel
• Faulty auto bystarter
• Clogged idle system or auto bystarter passages Lean mixture
Rich mixture
• Faulty auto bystarter
• Faulty float valve
• Float level too high
• Clogged air jets
• Dirty air cleaner
• Flooded carburetor
Backfiring at deceleration
• Lean mixture in idle system
• Improper air cut-off valve operation
Misfiring during acceleration
• Faulty ignition system
• Lean mixture
• Faulty accelerating pump
Engine idles roughly, stalls or runs poorly
• Clogged fuel system
• Ignition malfunction
• Rich or lean mixture
• Contaminated fuel
• Intake air leak
• Incorrect idle speed
• Incorrectly adjusted pilot screw
• Clogged idle system or auto bystarter passages
• Incorrectly adjusted float level
• Clogged fuel jets
• Faulty float valve
• Float level too low
• Clogged fuel system
• Intake air leak
• Improper vacuum piston operation
• Improper throttle operation
FILLY LX 50
5-4