Owner`s manual
Troubleshooting
Tips 137
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 POSSIBLE CAUSES
4. Start by following
normal starting
procedure
ENGINE DOES
NOT FIRE
ENGINE STARTS
BUT SOON
STOPS
2. Try spark test*
GOOD SPARK
WEAK OR NO
SPARK
NOT REACHING
CARBURETOR
3. Test cylinder
compression*
CORRECT
LOW
1. Check the fuel
flow to carburetor
REACHING
CARBURETOR
• No fuel in fuel tank
• Clogged fuel tube or
fuel strainer screen
(p.34)
• Sticking float valve*
• Clogged fuel fill cap
breather tube (p.34)
• Faulty spark plug (p.54)
• Fouled spark plug (p.54)
• Faulty ignition control
module*
• Broken or shorted spark
plug wire
• Faulty exciter coil
• Broken or shorted ignition
coil
• Faulty engine stop button
• Loose or disconnected
ignition system wires
• Faulty ignition pulse
generator*
• Valve stuck open
• Worn cylinder and piston
ring*
• Leaking/damaged
cylinder head gasket
• Improper valve timing*
• Seized valve
• Improper choke operation
• Pilot screw incorrectly
adjusted*
• Insulator leaking
• Improper ignition timing
(Faulty ignition coil or
ignition pulse generator)*
• Fuel contaminated
• Improper hot start
operation (p. 53)
• Carburetor flooded
• Choke closed
• Throttle valve open
• Air cleaner dirty (p. 43)
5. Removed and
inspect spark plug
6. START WITH CHOKE ON
DRY
WET PLUG
POOR PERFORMANCE AT LOW AND UNSTABLE
IDLE SPEED
CHECK POSSIBLE CAUSES
1. Check if air
cleaner is over-
oiled (P.44)
CORRECT
INCORRECT
INCORRECT
LEAKING
CLOGGED
WAKE OR
INTERMITTENT
SPARK
CORRECT
NOT LEAKING
NOT CLOGGED
GOOD SPARK
2.
Check if the insulator
is leaking
3. Check carburetor
pilot screw
adjustment (P.126)
4. Check carburetor
jets and accelerator
pump for clogs
5. Try spark test
INCORRECT
CORRECT
6. Check the throttle
position sensor*
LOW
CORRECT
7. Test cylinder
compression.
• Over-oiled air cleaner.
• Loose insulator clamp
• Damaged insulator
• Fuel-air mixture too
lean (Turn the pilot
screw out) (P.126)
• Fuel-air mixture too rich
(Turn the pilot screw in)
(P.126)
• Contaminants in the
fuel
• Not cleaned frequently
enough (P.121)
• Faulty, carbon or wet
fouled spark pulg (P.128)
• Faulty ignition control
module*
• Faulty alternator*
• Faulty ignition coil*
• Broken or shorted
spark plug wire.
• Faulty ignition pulse
generator*.
• Loose or disconnected
ignition system wires
• Faulty engine stop button
• Faulty throttle position
sensor*
• Ring worn
• Cylinder worn or
damaged*
• Piston worn or
damaged*
• Head gasket not
sealing
• Valve stick open
POOR PERFORMANCE AT HIGH SPEED
CHECK POSSIBLE CAUSES
1. Disconnect fuel
line at carburetor
and check for
clogging (P.34)
UNRESTRICTED
FUEL FLOW
FUEL FLOW
RESTRICTED
CLOGGED
DIRTY
INCORRECT
LOW
WEAK OR
INTERMITTENT
SPARK
NOT CLOGGED
CORRECT
CORRECT
GOOD SPARK
2. Remove air
cleaner (P.43)
4. Check carbureator
jets for clogging
5. Check valve
timing
6. Try spark test
7. Test cylinder
compression.
AIR CLEANER
NOT DIRTY
3. Install a larger
carburetor main
jet (P.124)
CORRECT
CONDITION
WORSE
• Lack of fuel in tank
(P.34)
• Clogged fuel line
(P.34)
• Clogged fuel fill
cap breather tube
(P.34)
• Clogged fuel valve
(P.34)
• Clogged fuel filter
(P.35)
• Not cleaned
frequently enough
(P.43)
• Jet size wrong, rejet
in the opposite
direction (P.126)
• Contaminants in
the fuel
• Cam sprocket not
installed properly
• Faulty, carbon or wet
fouled spark pulg
(P.128)
• Faulty ignition control
module*
• Faulty alternator*
• Faulty ignition coil*
• Broken or shorted
spark plug 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
• Improper valve timing
• Valve stick open
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