Fuel System Troubleshooting - Honda Motorcycle Service Manual

TROUBLESHOOTING
Engine won't start
No fuel to carburetor
-
Fuel strainer clogged
- Fuel tube clogged
-
Float valve stuck
-
Float level misadjusted
-
Fuel tank breather tube (or hole) clogged
-
Fuel pump malfunction
-
Fuel auto valve malfunction
Too much fuel getting to the engine
-
Air cleaner clogged
-
Flooded carburetor
.
lntake air leak
.
Fuel contaminatedldeteriorated
Slow circuit or starting enrichment valve circuit clogged
Lean mixture
.
Fuel jets clogged
Float valve faulty
.
Float level too low
.
Fuel line restricted
.
Carburetor air vent hole (or tube) clogged
lntake air leak
-
Fuel pump malfunction
.
Fuel auto valve malfunction
Vacuum piston faulty (CV type only) .
Throttle valve faultv
Engine stalls, hard t o start, rough idling
-
Fuel line restricted
Ignition malfunction
Fuel mixture too leanirich
.
Fuel contaminatedldeteriorated
.
lntake air leak
.
Idle speed misadjusted
.
Fuel pump malfunction
.
Fuel auto valve malfunction
-
Air screw or pilot screw misadjusted
-
Slow circuit or starting enrichment valve circuit clogged
Float level misadjusted
.
Fuel tank breather tube (or hole) clogged
.
Evaporative emission carburetor air vent control valve
(EVAP CAV control valve) faulty
Hoses of the emission control system faulty
-
Evaporative emission purge control valve (EVAP purge
control valve) faulty
Afterburn or misfiring during acceleration
.
Air cut-off valve malfunction
Lean mixture in slow circuit
.
Secondary air supply system faulty
.
Hose of emission control system faulty
Afterburn or misfiring during acceleration
.
lgnition system faulty
-
Fuel mixture too lean
Rich mixture
.
Choke valve or starting enrichment valve in ON position
Poor performance (driveabilityl and poor fuel economy
-
Float valve faulty
.
Float level too high
.
Fuel system clogged
Air jets clogged
.
lgnition malfunction
Air cleaner element contaminated
Faulty evaporative emission carburetor air vent control
.
Flooded carburetor
valve (EVAP CAV control valve)
Damaged/misconnected emission control system house
Hesitation during acceleration
.
Accelerator pump malfunction
Date of Issue: March. 1995
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HONDA MOTOR CO.,LTD.