Supersedes Service Instruction No. 1485 July 2, 2003 MODELS AFFECTED All Lycoming reciprocating aircraft engines unless installed in a rotary-wing aircraft. TIME OF COMPLIANCE Half way to recommended TBO or at 1000 hours of operation, whichever occurs first or earlier at owner’s discretion or anytime valve sticking is suspected. As a product improvement, Lycoming has introduced a new exhaust valve...

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...

DATE: July 1, 2002 MODELS AFFECTED All Lycoming aircraft engines. TIME OF COMPLIANCE At engine start in cold weather. In extremely low temperatures, oil congeals, battery capacity is lowered, and the starter can be overworked. Improper cold weather starting can result in abnormal engine wear, reduced performance, shortened time between overhauls, or failure for the engine to operate properly.

DATE: January 26, 2001 MODELS AFFECTED O-235 aircraft engines operated under the authority of the French Direction Generale De L’Aviation Civile (DGAC.) TIME OF COMPLIANCE At owner’s discretion. The French DGAC has reported a significant number of O-235 cylinder barrel failures in France. These failures have initiated from corrosion pits at the base area of the cylinder.

DATE: January 11, 2001 MODELS AFFECTED All O-540-F1B5 model engines installed in Robinson R-44 helicopters. TIME OF COMPLIANCE At overhaul. Textron Lycoming has revised the counterweight tuning to lessen vibration characteristics for the O-540- F1B5 model engine installed in those Robinson R-44 helicopter which use the new Robinson fanshaft P/N C007-5.

DATE: December 20, 2000 MODELS AFFECTED Textron Lycoming VO-435-B1A model engines. TIME OF COMPLIANCE At overhaul or whenever the accessory drive gear and shaft assembly P/N 76327 is disassembled. Any time the accessory drive gear and shaft assembly, P/N 76327, is disassembled, replace the three standard dowels, P/N 76323, connecting the gear and shaft with oversize dowels P/N 76323-P15.

Supersedes Service Instruction No. 1502 December 19, 2000 MODELS AFFECTED All Textron Lycoming IO-360-L2A aircraft engines. TIME OF COMPLIANCE Whenever the engine has vapor related problems, or at owner’s discretion. To reduce the possibility of vapor related problems in aircraft employing IO-360-L2A model engines, the flow divider should be modified into an inverted flow divider.

Supersedes Service Instruction No. 1304H November 12, 1999 MODELS AFFECTED All Textron Lycoming aircraft engines. TIME OF COMPLIANCE Whenever a nameplate is lost or an engine modification affects model designation. A replacement nameplate, to replace one that has been lost, will be issued only upon written request when accompanied by a document from the FAA authorizing a replacement nameplate.