The FAA has issued an emergency Airworthiness Directive (AD), effective immediately, for all Teledyne Continental Motors (TCM) 240, 360, 470, and 520 series reciprocating engines.
The emergency AD results from TCM reporting three occurrences of rapid wear on the face of hydraulic lifters, according to the AD, which notes that this condition, if not corrected, could result in loss of engine power and loss of control of the airplane.
TCM issued a Mandatory Service Bulletin Nov. 3, which describes the procedures for inspecting engines for hydraulic lifters and replacing those lifters if installed. FAA officials noted they have reviewed and approved the Mandatory Service Bulletin.
Owners must have their engines inspected before further flight, according to the AD.