Lycoming TIO-540-A1A, Operator'S Manual

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LYCOMING OPERATOR’S MANUAL SECTION 3
TIO-540 SERIES – ANGLE VALVE CYLINDER HEADS OPERATING INSTRUCTIONS
a. Head the aircraft into the wind.
b. Leave mixture in “Full Rich”.
c. Operate the engine on the ground only with the propeller in minimum blade angle setting.
d. Warm up at approximately 1000-1200 RPM. Avoid prolonged idling and do not exceed 2200 RPM on
the ground.
e. Engine is warm enough for take-off when the throttle can be opened without the engine faltering
Take-off with turbocharged engines should not be started if indicated lubricating oil pressure due to
cold temperature, is above maximum. Excessive oil pressure can cause over boost and consequent
engine damage.
6. GROUND CHECK.
a. Warm up as directed above.
b. Check both oil pressure and oil temperature.
c. Leave mixture in “Full Rich”.
d. (Where applicable.) Move the propeller control through its complete range to check operation and
return to full low pitch position. Full feathering check (twin engine) on the ground is not
recommended but the feathering action can be checked by running the engine between 1000-1500
RPM; then momentarily pulling the propeller control into the feathering position. Do not allow the
RPM to drop more than 500 RPM.
e. A proper magneto check is important. Additional factors, other than the ignition system, affect
magneto drop-off. They are load-power output, propeller pitch and mixture strength. The important
thing is that the engine runs smoothly because magneto drop-off is affected by the variables listed
above. Make the magneto check in accordance with the following procedures.
(1) (Controllable Pitch Propeller.) With propeller in minimum pitch angle, set the engine to produce
50-65% power as indicated by the manifold pressure gage unless otherwise specified in the aircraft
manufacturer’s manual. Set the mixture control to the full rich position. At these settings, the
ignition system and spark plugs must work harder because of the greater pressure within the
cylinders. Under these conditions ignition problems, if they exist, will occur. Mag checks at low
power settings will only indicate fuel-air distribution quality.
NOTE
Aircraft that are equipped with fixed pitch propellers, or not equipped with manifold
pressure gage, may check magneto drop-off with engine operating at approximately 2100-
2200 RPM.
(2) Switch from both magnetos to one and note drop-off, return to both until engine regains speed and
switch to the other magneto and note drop-off, then return to both. Drop-off should not exceed 175
RPM and should not exceed 50 RPM between magnetos. A smooth drop-off past the normal
specification of 175 RPM is usually a sign of a too lean or too rich mixture.
Revised August 2006 3-3