Service Instruction No. 1290F DATE: July 24, 2009 WEBSITE PUBLISH DATE: June 17, 2025 due to frequent requests. MODELS AFFECTED: All Lycoming wide cylinder flange engines identified by the suffix “A” or “E” after the engine serial number and incorporating body-fit thru-studs such as: O, IO, AIO, AEIO and LIO-320 series engines O, IO, AIO, AEIO, HIO, LIO, TO and TIO-360 series engines O, IO, AEIO...

DATE: April 25, 2003 MODELS AFFECTED All Lycoming aircraft engines. TIME OF COMPLIANCE Whenever a P/N STD-1409 nut is removed from the crankcase parting line in the sump or from any other application on the engine. Any time a P/N STD-1409 nut is removed from the crankcase parting line in the sump or from any other location (such as the oil pump body on TIO and TIGO-541 models, the magnetos and oil...

January 23, 2014 To all owners and operators of Lycoming engine model O-360-A4M installed in Piper Archer III with AVStar carburetor model AV10-6102. This Service Letter is notification of the following two product improvements by AVStar to carburetor model AV10-6102 (Lycoming P/N 61C26051). These product improvements have been incorporated into new O-360-A4M engines with Serial Numbers L-42322...

DATE: March 17, 2009 MODELS AFFECTED Rebuilt, overhauled, or repaired Lycoming engines with the following cylinder kits installed: Engine Model Cylinder Kit O-320-H2AD 05K21119 (L)O-360-E1A6D 05K21121 (L)TO-360-E1A6D 05K21122 All Cylinder Kits P/N 05K21119, 05K21121, and 05K21122 that were shipped between November 20, 2008 and February 12, 2009. TIME OF COMPLIANCE For uninstalled cylinder kits...

Supersedes Service Instruction No. 1343B March 10, 2016 MODELS AFFECTED The following Wide Cylinder Flange Engines that are equipped with a front crankcase mounted propeller governor: O, IO, LIO, AIO, AEIO-320 Series O, LO, IO, LIO, AIO, AEIO, TO, TIO-360 Series O, IO, AEIO, TIO, LTIO-540 Series IO-580 Series IO-720 TIME OF COMPLIANCE At each installation of propeller governor set screw REASON FOR...

DATE: March 10, 2016 MODELS AFFECTED The following Wide Cylinder Flange Engines that are equipped with a front crankcase mounted propeller governor: O, IO, LIO, AIO, AEIO-320 Series O, LO, IO, LIO, AIO, AEIO, TO, TIO-360 Series O, IO, AEIO, TIO, LTIO-540 Series IO-580 Series IO-720 TIME OF COMPLIANCE At owner’s discretion. This Service Instruction includes inspection instructions for the propeller...