Fuel System Troubleshooting; Engine Cranks But Won't Start; Lean Mixture; Engine Stalls, Hard To Start, Rough Idling - Honda Fourtrax Rancher AT 2004 Service Manual

FUEL SYSTEM
TROUBLESHOOTING
Engine cran ks but won't sta rt
• No fuel in tank
• No fuel to ca rburetor
- Clogged fuel strainer
- Clogged fuel line
- Clogged fuel tank breather hose
• Too much fuel getting to the engine
- Clogged air cleaner
- Flooded carburetor
• Intake air leak
• Contaminated/deteriorated fuel
- Clogged jets
• Clogged starting enrichment (SE) valve circuit
• Improper choke operation
• Improper throttle operation
• No spark at plug (f aulty ignition system - (page 20-4))
lean milCture
• Clogged fuel jets
• Faulty float valve
• Float level too low
• Restricted fualline
• Clogged carburetor ai r vent hose
• Restricted fu el tank breather hose
• Intake air leak
• Faulty throttle valve
Rich mixture
• SE valve open (ON)
• Clogged air jets
• Faulty float valve
• Float level too high
• Dirty air cleaner
• Worn jet needle or needle jet
• Faulty vacuum piston
Engine stalis, hard t o st art, rough idling
• Restricted fuel line
• Fuel mixture too lean/rich
• Contaminated/deteriorated fuel
- Clogged jets
• Intake air leak
• Misadjusted idle speed
• Restricted fuel tank breather hose
• Dirty air cleaner
• Misadjusted pilot screw
• Faulty ignition system (page 20-4)
Afterburn when engine braking is used
• lean mixture in slow circuit
• Faulty ignition system (page 20-4)
Backfiring or misfirin g dUring accelerat ion
• lean mixture
• Faulty ignition system (page 20-4)
Poor performance (drive-abilitv) and poor fuel economy
• Clogged fuel system
• Faulty ignition system (page 20-4)
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