Ⅲ
MAINTAINENACE - TROUBLESHOOTING
SYMPTOM
POSSIBLE CAUSE
SOLUTION
Spark plug bridging?
Check gap, insulation or replace
spark plug.
Carbon deposit on spark plug?
Clean or replace spark plug.
Short circuit due to deficient
spark plug
insulation?
Check spark plug insulation, replace
if worn.
Difficult to start, "fuel is
available, but no
SPARK at spark
plug".
Improper spark plug gap?
Set to proper gap.
ON/OFF switch is shorted?
Check switch wiring, replace switch.
Ignition coil defective?
Replace ignition coil.
Improper spark gap, points dirty?
Set correct spark gap and clean
points.
Condenser insulation worn or
short circuiting?
Replace condenser.
Difficult to start, "fuel is
available, and SPARK
is present at the
spark plug".
Spark plug wire broken or short
circuiting?
Replace defective spark plug wiring.
Wrong fuel type?
Flush fuel system, and replace with
correct type of fuel.
Water or dust in fuel system?
Flush fuel system.
Air cleaner dirty?
Clean or replace air cleaner.
Difficult to star t, "fuel
is available, spark
is present and
compression is
normal".
Choke Open?
Close Choke.
Suction/exhaust valve stuck or
protruded?
Re-seat valves.
Piston ring and/or cylinder worn?
Replace piston rings and or piston.
Cylinder head and/or spark plug
not tightened
properly?
Torque cylinder head bolts and spark
plug.
Difficult to star t, "fuel
is available, spark
is present and
compression is low".
Head gasket and/or spark plug
gasket
damaged?
Replace head and spark plug
gaskets.
Fuel not available in fuel tank?
Fill with correct type of fuel.
Fuel filter clogged?
Replace fuel filter.
Fuel tank cap breather hole
clogged?
Clean or replace fuel tank cap.
No fuel present at the
carburetor.
Air in fuel line?
Bleed fuel line.
