AD FAA-2008-0420

The FAA is superseding an existing airworthiness directive (AD) for Lycoming Engines IO, (L)IO, TIO, (L)TIO, AEIO, AIO, IGO, IVO, and HIO series reciprocating engines, TCM TSIO-360-RB reciprocating engines, and Superior Air Parts, Inc. IO-360 series reciprocating engines with certain Precision Airmotive LLC RSA-5 and RSA-10 series fuel injection servos. That AD currently requires inspecting servo plugs for looseness and damage on fuel injection servos that have a servo plug gasket, part number (P/N) 365533, installed, and if loose, inspecting the servo regulator cover threads for damage, inspecting the gasket for damage, reinstalling acceptable parts, and torquing the servo plug to a new, higher torque to maintain the proper clamp-up force between the plug and cover. This AD requires the same inspections, except if the plug is found loose, servo plug gasket, P/N 365533, must be replaced with a new, improved gasket, P/N 2577258. This AD also requires replacement by December 31, 2009, of servo plug gaskets, P/N 365533, manufactured and made available on or after August 22, 2006, as mandatory terminating action to the repetitive inspections required by this AD. This AD also prohibits the installation of any servo plug gasket, P/N 365533. This AD also clarifies the TCM engine model applicability, and adds Bendix RSA-5 and RSA-10 series fuel injection servos to the applicability. This AD results from Precision Airmotive LLC introducing the installation of a new improved servo plug gasket, P/N 2577258, to the affected Precision Airmotive LLC RSA-5 and RSA-10 series, and Bendix RSA-5 and RSA-10 series, fuel injection servos. We are issuing this AD to prevent a lean running engine, which could result in a substantial loss of engine power and subsequent loss of control of the airplane.