Lycoming IVO-540 Series, Operator'S Manual

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LYCOMING OPERATOR’S MANUAL SECTION 3
VO, IVO & TIVO-540 SERIES OPERATING INSTRUCTIONS
CAUTION
ENGINES EQUIPPED WITH PISTON OIL JE TS – DURING EXTREME COLD WEATHER
(-20°F AND BELOW) IT WILL BE NECESSARY TO PRE-HEAT THE ENGINE FOR A
SUFFICIENT LENGTH OF TIME TO ALLOW THE HEAT TO PENETRATE
CRANKSHAFT AND LOOSEN CONGEALED OIL IN PASSAGES BETWEEN THE MAIN
BEARINGS AND CONNECTING ROD BEARINGS.
BECAUSE THE HEAT PENETRATES THE ALUMINUM CRANKCASE MORE RAPIDLY
THAN THE STEEL CRANKSHAFT, IT IS POSSIBLE FOR THE OIL TO CIRCULATE
AROUND THE ANNULUS OF THE MAIN BEARING AND THROUGH THE PISTON OIL
JETS. THIS CIRCULATION, WHILE GIVING A SAFE READING ON THE OIL
TEMPERATURE AND OIL PRESSURE GAUGES, COULD OCCUR WITHOUT
DISLODGING THE CONGEALED OIL IN THE CRANKSHAFT OIL PASSAGES,
CAUSING OIL STARVATION TO THE CONNECTING ROD BEARINGS.
5. GROUND RUNNING AND WARM-UP.
a. Leave aircraft contro l in “Full Rich”.
b. Idle engine until oil pressure reaches 50 psi mini mum. Consult airframe manufacturer’s handbook for
rotor and engine speed.
c. Limit ground running to minimum time necessary to warm engine for take-off.
6. CHECKS BEFORE TAKE-OFF.
a. Check both oil temperature and oil pressure.
b. Set carburetor air heat control for “Full Heat” to check proper operation. Loss of RPM and manifold
pressure will result if heat control is working properly. Return heat cont rol to “cold” position after
check.
c. With rotor angle at minimum pitch, increase RPM to 3200 and check magneto drop-off. Switch from
both magnetos to one and note drop-off, return to both magnetos until engine regains speed and switch
to the other magneto and note drop-off, then retu rn to “both”. Drop-off should not exceed 200 RPM
on either magneto and should be within 50 RPM of each other.
NOTE
Do not operate too long on one magneto, 2 to 3 seconds is sufficient and will minimize plug
fouling.
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