Service Bulletin No. 593 B

Intake Valve P/N 17A23942 Inspection for Date Stamp

  • Publications

July 6, 2015


Lycoming Engine Models: IO-540-AC1A5, (L)TIO-540-V2AD, TIO-540- AJ1A, TIO-540-W2A, TO-360-C1A6D, TIO-360-C1A6D, TIO-541-E Series, TIGO-541-E1A, and IO-580-A1A Applies to:

  • Engines with the serial numbers identified in Table 3
  • Cylinder kits identified in Table 2 shipped from the factory between March 2, 2009 and August 17, 2011
  • Intake valves (P/N 17A23942) sold as spares with the date stamp identified in Table 1, and shipped from the factory between March 2, 2009 and August 17, 2011. (BOTH conditions must be met, the date stamp on the valve stem AND within the shipping date range.)

At next maintenance, 50 hour inspection, or on or before July 23, 2015, whichever occurs first.


Date Stamp 4 11 does not apply to this Service Bulletin. Warranty consideration is available until 07/23/2015. See Warranty Instructions for further details. 

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