Step 6. Required Inspections During Break-In (50-Hour Operation) - Lycoming IO-390-D Series Installation And Operation Manual

CAUTION
I. Decrease altitude at low cruise power and closely monitor the engine instruments. Do not do
long descents at low manifold pressure. Do not decrease altitude too rapidly. The engine
temperature could decrease too quickly.
J. After landing and shutdown, examine the engine for oil and fuel leaks. Identify and correct
the cause of any leaks.
K. Calculate oil consumption and compare the limits given in Appendix A.
L. If the oil consumption value is above the limits in Appendix A, identify and correct the cause.
Complete this flight test again, up to and including this step before releasing the aircraft for
service.
M. Complete the inspections identified in the "Required Inspections" section in this chapter.
N. Correct any problems before releasing the engine back into service.
O. Continue to operate the engine at cruise power settings of 65% to 75% for 50 hours or until
oil consumption stabilizes.

Step 6. Required Inspections During Break-In (50-Hour Operation)

During the next 50 hours of flight, complete the following inspections per Chapter 05-20 in the IO-
390-D Series Engines Maintenance Manual:
• Visual Inspection
• 10-Hour Initial Engine Inspection Checklist
• 25-Hour Engine Inspection Checklist
• 50-Hour Engine Inspection Checklist
Engine Initiation
Page 34
IO-390-D Series Engine Installation and Operation Manual
DO NOT DO CLOSED THROTTLE DESCENTS. CLOSED THROTTLE
OPERATION DURING DESCENTS WILL CAUSE RING FLUTTER
WHICH CAN CAUSE DAMAGE TO THE CYLINDERS AND PISTON
RINGS.
0.006 x BHP x 4 ÷ 7.4 = Qt./Hr.
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March 2020