Lycoming AIO-320, Operator'S Manual

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SECTION 6 LYCOMING OPERATOR’S MANUAL
TROUBLE-SHOOTING IO-320 SERIES
TROUBLE PROBABLE CAUSE REMEDY
Failure of Engine to Idle Properly Incorrect idle mixture Adjust mixture.
Leak in induction system Tighten all connections in the
induction system. Replace any
parts that are defective.
Incorrect idle adjustment Adjust throttle stop to obtain
correct idle.
Uneven cylinder compression Check condition of piston rings
and valve seats.
Faulty ignition system Check entire ignition system.
Insufficient fuel pressure Adjust fuel pressure.
Low Power and Uneven Running Mixture too rich indicated by
sluggish operation, red exhaust
flame at night. Extreme cases
indicated by black smoke from
exhaust. Readjustment of fuel injector by
authorized personnel is indicated.
Mixture too lean; indicated by
overheating or backfiring. Check fuel lines for dirt or other
restrictions. Readjustment of fuel
injector by authorized personnel is
indicated.
Leaks in induction system Tighten all connections. Replace
defective parts.
Defective spark plugs Clean and gap or replace spark
plugs.
Improper fuel Fill tank with fuel of
recommended grade.
Magneto breaker points not
working properly Clean points. Check internal
timing of magnetos.
Defective ignition wire Check wire with electric tester.
Replace defective wire.
Defective spark plug terminal
connectors. Replace connectors on spark plug
wire.
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