Lycoming AIO-320, Operator'S Manual

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SECTION 3 LYCOMING OPERATOR’S MANUAL
OPERATING INSTRUCTIONS IO-320 SERIES
7. OPERATION IN FLIGHT.
ctions for recommended power settings.
b.
Fuel Mixture Leaning Procedure.
Improper fuel/air mixture during flight is responsible for many engine problems, particularly during
take-off and climb power settings. The procedures described in this manual provide proper fuel/air
mixture when leaning Lycoming engines; they have proven to be both economical and practical by
eliminating excessive fuel consumption and reducing damaged parts replacement. It is therefore
recommended that operators of all Lycoming aircraft power plants utilize the instructions in this
publication any time the fuel/air mixture is adjusted during flight.
Manual leaning may be monitored by exhaust gas temperature indication, fuel flow indication, and
by observation of engine speed and/or airspeed. However, whatever instruments are used in
monitoring the mixture, the following general rules should be observed by the operator of Lycoming
engines.
GENERAL RULES
Never exceed the maximum red line cylinder head temperature limit.
For maximum service life, cylinder head temperatures should be maintained below 435°F
(224°C) during high performance cruise operation and below 400°F (205°C) for economy
cruise powers.
Do not manually lean engines equipped with automatically controlled fuel system.
Maintain mixture control in “Full Rich” position for rated take-off, climb and maximum
cruise powers (above approximately 75%). However, during take-off from high elevation
airport or during climb, roughness or loss of power may result from over-richness. In such a
case adjust mixture control only enough to obtain smooth operation – not for economy.
Observe instruments for temperature rise.
Always return the mixture to full rich before increasing power settings.
Operate the engine at maximum power mixture for performance cruise powers and at best
economy mixture for economy cruise power; unless otherwise specified in the airplane
owners manual.
During let-down flight operations it may be necessary to manually lean uncompensated
fuel injected engines to obtain smooth operation.
1. LEANING TO EXHAUST GAS TEMPERATURE GAGE.
a. Normally aspirated engines with fuel injectors.
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