Cylinder Crack Alert

The FAA has issued a Special Airworthiness Information Bulletin recommending that owners of certain larger Continental engines with ECi cylinder assemblies inspect the cylinders for cracks every 50 hours after theyve accumulated more than 500 hours in service. The bulletin affects 520- and 550-series engines with certain ECi components. The cracks started showing up in 2003 and start as fatigue cracks that eventually go through the cylinder wall near the exhaust valve seat. This causes decreased compression but is unlikely to cause separation of the cylinder from the engine, according to the FAA. The bulletin recommends a standard compression test and soapy water test on the cylinders at each oil change and that cracked cylinders be replaced with improved models. The cracks have appeared as early as 253 hours and as late as 1,489 hours, though the average is 891. The recommendations in the bulletin are not mandatory.