Troubleshooting - Honda CRF250X 2007 Owner's Manual & Competition Handbook

Troubleshooting

The items that are serviceable using this Manual
are followed by the page number reference in
parenthesis. The items that require use of the
Honda Service Manual are followed by an
asterisk (*).
ENGINE DOES NOT START OR IS HAND TO START
CHECK
1. Check the fuel NOT REACHING
flow to carburetor
CARBURETOR
REACHING
CARBURETOR
2. Try spark test WEAK OR NO
SPARK
GOOD SPARK
3. Test cylinder LOW
compression*
CORRECT
4. Start by following ENGINE STARTS
normal starting
BUT SOON
procedure
STOPS
ENGINE DOES
NOT FIRE
5. Removed and WET PLUG
inspect spark plug
DRY
6. START WITH CHOKE ON
144
Tips
POOR PERFORMANCE AT LOW AND UNSTABLE
IDLE SPEED
CHECK
1. Check if air
cleaner is over-
oiled (P.51)
CORRECT
POSSIBLE CAUSES
2. Check if the intake
• No fuel in fuel tank
tube is leaking
• Clogged fuel line or fuel
filter (P.41, 42)
NOT LEAKING
• Sticking float valve*
• Clogged fuel fill cap
breather tube (P.41)
3. Check carbureator
pilot screw
• Faulty spark plug (P.61)
adjustment*
• Fouled spark plug
(P.61)
CORRECT
• Faulty ignition control
module*
• Faulty exciter coil
• Broken or shorted direct
4. Check carburetor
ignition coil
jets and accelerator
• Faulty engine stop button
pump for clogs
• Loose or disconnected
ignition system wires
NOT CLOGGED
• Faulty ignition pulse
generator*
5. Try spark test
• Valve stuck open
• Worn cylinder and piston
GOOD SPARK
ring*
• Leaking/damaged
cylinder head gasket
• Improper valve timing*
• Seized valve
• Improper choke operation
• Pilot screw incorrectly
adjusted*
6. Check the throttle
• Insulator leaking
position sensor*
• Improper ignition timing
(Faulty direct ignition
CORRECT
coil or ignition pulse
generator)*
• Fuel contaminated
• Improper hot start
7. Test cylinder
operation (P.60)
compression*
CORRECT
• Carburetor flooded
• Choke closed
• Throttle valve open
• Air cleaner dirty (P.51)
POSSIBLE CAUSES
• Over-oiled air cleaner.
INCORRECT
LEAKING • Loose insulator clamp
• Damaged insulator
INCORRECT • Fuel-air mixture too
lean (Turn the pilot
screw out)*
• Fuel-air mixture too rich
(Turn the pilot screw in)*
CLOGGED • Contaminants in the
fuel
• Not cleaned frequently
enough (P.131)
WEAK OR
• Faulty, carbon or wet
INTERMITTENT fouled spark pulg (P.61)
• Faulty ignition control
SPARK
module*
• Faulty alternator*
• Faulty direct ignition coil*
• Broken or shorted
direct ignition coil wire.
• Faulty ignition pulse
generator*.
• Faulty throttle position
INCORRECT
sensor*
LOW • Ring worn
• Cylinder worn or
damaged*
• Piston worn or
damaged*
• Head gasket not
sealing
POOR PERFORMANCE AT HIGH SPEED
CHECK
1. Disconnect fuel FUEL FLOW
line at carburetor RESTRICTED
and check for
clogging (P.41)
UNRESTRICTED
FUEL FLOW
2. Remove air
DIRTY
cleaner (P.51)
AIR CLEANER
NOT DIRTY
3. Check carbureator CLOGGED
jets for clogging
NOT CLOGGED
4. Check valve INCORRECT
timing
CORRECT
5. Try spark test WEAK OR
INTERMITTENT
GOOD SPARK
SPARK
6. Test cylinder LOW
compression*
CORRECT
POSSIBLE CAUSES
• Lack of fuel in tank
(P.41)
• Clogged fuel line
(P.41)
• Clogged fuel fill
cap breather tube
(P.41)
• Clogged fuel valve
(P.41)
• Clogged fuel filter
(P.42)
• Not cleaned
frequently enough
(P.51)
• Contaminants in
the fuel
• Cam sprocket not
installed properly
• Faulty, carbon or wet
fouled spark pulg
(P.61)
• Faulty ignition control
module*
• Faulty alternator*
• Faulty direct ignition coil*
• Broken or shorted
direct ignition coil wire.
• Faulty ignition pulse
generator*.
• Loose or disconnected
ignition system wires
• Faulty engine stop button
• Ring worn
• Cylinder worn or
damaged
• Piston worn or
damaged
• Head gasket not
sealing