MASTERPAC PC4012 Series, Operation Manual

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19
MAINTENANCE
SYMPTOM
POSSIBLE CAUSE SOLUTION
Suction/exhaust valve stuck
or protruded?
Re-seat valves.
Piston ring and/or cylinder
worn?
Replace pistion rings and or
pistion.
Cylinder head and/or spark
plug not tightened properly?
Torque cylinder head bolts and
spark plug.
Difficult to start,
"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 cock does not open
properly?
Apply lubricant to loosen fuel
cock level, replace if necessary.
Fuel filter clogged? Replace fuel filter.
Fuel tank cap breather hole
cloged?
Clean or replace fuel tank cap.
No fuel present at
carburetor.
Air in fuel line? Bleed fuel line.
Air cleaner not clean? Clean or replace air cleaner.
Improper level in carburetor?
Check float adjustment, re-build
carbureator.
"Weak in power"
compression is
proper and does
not mistire.
Defective Spark plug? Clean or replace spark plug.
Water in fuel system?
Flush fuel system, and replace
with correct type of fuel.
Dirty spark plug? Clean or replace spark plug.
"Weak in power"
compression is
proper but mistires.
Ignitiion coil defective? Replace ignition coil.
Spark plug heat value
improper?
Replace with correct type of
spark plug.
Correct type of fuel? Replace with correct type of fuel.
Engine overheats.
Cooling fins dirty? Clean cooling fins.
Governor adjusted correctly? Adjust governor.
Governor spring defective? Replace governor spring.
Rotational speed
fluctuates.
Fuel flow restricted?
Check entire fuel system for
leaks or clogs.
Recoil mechanism clogged
with dust and dirt?
Clean recoil assembly with soap
and water.
Recoil starter
malfunction.
Spiral spring loose? Replace spiral spring.