Honda XL125LK, Owner'S Manual

Page: 76 / 243

6-3
dummyhead dummyhead
FUEL SYSTEM
TROUBLESHOOTING
Engine cranks but won’t start
• No fuel in tank
• No fuel to carburetor
– 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
• Improper choke operation
• Improper throttle operation
• No spark at plug (faulty ignition system – page 4-3)
Lean mixture
• Clogged fuel jets
• Faulty float valve
• Float level too low
• Restricted fuel line
• Clogged carburetor air vent hose
• Restricted fuel tank breather hose
• Intake air leak
• Faulty throttle valve
Rich mixture
• Choke valve closed
• Clogged air jets
• Faulty float valve
• Float level too high
• Dirty air cleaner
• Worn jet needle or needle jet
Engine stalls, hard to start, 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 4-3)
Afterburn when engine braking is used
• Lean mixture in slow circuit
• Faulty PAIR control valve
• Faulty PAIR check valve
• Clogged hose of the PAIR system
• Faulty ignition system (page 4-3)
Backfiring or misfiring during acceleration
• Lean mixture
• Faulty ignition system (page 4-3)
Poor performance (driveability) and poor fuel economy
• Clogged fuel system
• Fuel mixture too lean
• Faulty ignition system (page 4-3)