IO-390-D Series Engine Maintenance Manual
© 2020 Avco Corporation. All Rights Reserved
05-00
March 2020
Page 5
IO-390-D Series Engine Maintenance Manual
7.
General Engine Inspection Criteria
During visual inspection, replace engine components including the crankcase, oil sump, and
accessory housing with:
•
Replace the crankcase, oil sump, or accessory housing if there is any raised metal on surfaces
•
Replace the crankcase, oil sump, or accessory housing if there is any scratch, ding, dent, or
pit, that exceeds 0.050 in. (1.27 mm) depth
•
Replace the crankcase if the dowels do not fully seat into the crankcase holes
•
Replace any bent, damaged, or stripped studs, refer to Appendix A
8.
Requirements for Engine Maintenance
A.
These engines must be maintained using Lycoming Engines’ approved methods and
procedures.
B.
Refer to the latest revision of Service Bulletin No. SB-240 for a list of parts must be replaced
whenever they are removed.
9.
Approved Parts
CAUTION
LYCOMING DOES NOT GIVE APPROVAL FOR USE OF PARTS
MANUFACTURER APPROVAL (PMA) PARTS ON ITS ENGINES.
LYCOMING INSTALLATION INSTRUCTIONS DO NOT APPLY TO PMA
PARTS. EQUIPMENT FAILURE COULD OCCUR IF LYCOMING
INSTRUCTIONS ARE USED TO INSTALL PMA PARTS. DAMAGES
RELATED TO THE INSTALLATION OF PMA PARTS COULD VOID THE
WARRANTY.
Lycoming Engines recommends these engines be assembled, maintained, and overhauled using
only genuine Lycoming parts. (PMA parts have not been approved for use by Lycoming
Engines.)
Refer to the applicable parts catalog for genuine Lycoming parts.
Before installing a component, complete a check of the shelf-life of the part as per the latest
revision of Service Letter No. L247.
