Plug Replacement of Vapor Return Fitting on Piper installation of IO-360- B4A DATE: August 3, 2018 SUBJECT: Plug Replacement of Vapor Return Fitting on Piper installation of IO-360- B4A MODELS AFFECTED: IO-360-B4A

Alternate Oil Sump Fitting Configuration for Aerobatic Inverted Oil System DATE: August 3, 2018 SUBJECT: Alternate Oil Sump Fitting Configuration for Aerobatic Inverted Oil System MODELS AFFECTED: IO-540-K1K5 Engines Installed in ENAER T-35 Pillan Aircraft TIME OF COMPLIANCE: As required by the aircraft manufacturer, based on parts availability* REASON FOR REVISION: Added additional section...

MAINTENANCE PROCEDURES AND SERVICE LIMITATIONS FOR VALVES DATE: February 18, 1977 MODELS AFFECTED: All Avco Lycoming opposed series aircraft engines. TIME OF COMPLIANCE: During periodic maintenance and when intake and exhaust valves are removed from cylinders.

SHELF LIFE REQUIREMENTS DATE: August 23, 2018 TO: All Owners and Operators of Lycoming Engines Aircraft Engines SUBJECT: Shelf Life Requirements REASON FOR REVISION: Added part numbers 37B19774-472, LW-12008, and STD-1934 to Table 1; Removed part number 951392 from Table 2; added part number AV951392 to Table 2

Lockplate installation for Induction Housing on TIO-540-AJ1A and IO-540-AC1A5 DATE: August 23, 2018 SUBJECT: Lockplate installation for Induction Housing on TIO-540-AJ1A and IO-540-AC1A5 MODELS AFFECTED: TIO-540-AJ1A, IO-540-AC1A5 TIME OF COMPLIANCE: Required at next Overhaul, or at owner’s discretion.

DATE RELEASED: November 2011 TITLE: O-320-E1A & -E2A Parts Catalog DOCUMENT PART NUMBER: PC-203-3 MODELS AFFECTED: O-320-E1A, O-320-E2A

Cylinder and Head Assembly Serviceable Life DATE: October 11, 2018 SUBJECT: Cylinder and Head Assembly Serviceable Life MODELS AFFECTED: All Lycoming Engines with Parallel Valve Cylinder and Head Assemblies (Table 1) shipped from Lycoming Engines between 1-SEP-2013 and 30-APR-2015 (excludes O-235 series) TIME OF COMPLIANCE: During Cylinder and Head Assembly removal for condition or overhaul

Recommended Engine Procedures for Purge of Vapor During Ground Operations DATE: January 7, 2019 SUBJECT: Recommended Engine Procedures for Purge of Vapor During Ground Operations MODELS AFFECTED: Lycoming engines equipped with fuel injection. TIME OF COMPLIANCE: As necessary during aircraft operations when symptoms of fuel vaporization are encountered. REASON FOR REVISION: Removed model specific...

Tappets and Lifters DATE: January 7, 2019 SUBJECT: Tappets and Lifters MODELS AFFECTED: All Lycoming engines TIME OF COMPLIANCE: At overhaul or at owner’s discretion REASON FOR REVISION: Added new engine model, TEO-540 Series to Table 3.