AOPA has concerns about the recommendations of a mandatory service bulletin issued by Continental Motors for the replacement of certain camshaft gears on many Continental IO-520- and IO-550-series engines, and some Continental IO-470 engines.
AOPA will work with aircraft owners groups and the FAA to explore the areas of concern that the mandatory service bulletin raises, and develop common-sense mitigations that address safety, said David Oord, AOPA senior director of regulatory affairs.
Most members face no required action unless the FAA makes the mandatory service bulletin, which was issued March 29, compulsory by issuing an airworthiness directive to enforce it, Oord said.
Camshaft replacement requires splitting the engine’s crankcase, raising concerns about the adverse effects of disassembling an engine when not required for an overhaul or a major repair, Oord said.
He noted that for some aircraft with Pernold-case engines, installing the thicker camshaft also would require modifying the engine case.
AOPA will remain engaged with the FAA to ensure that owners’ concerns are addressed, and will keep members updated about the issue, Oord said.