The FAA has expanded its AD for certain Continental engines regarding potential manufacturing errors with the engines’ crankshaft counterweights. The original AD has been superseded and several new models added. “Since the FAA issued AD 2023-04-08, the FAA determined that IO-470-A, -C, -F, and -LO; and TSIO-360-F and -FB model engines are also affected by the unsafe condition and should be added to the applicability,” a notice says. “Additionally, the FAA determined that the limitations in the special flight permit paragraph, specifying ‘no metal contamination in the oil filter,’ did not account for trace metal particles that may be found in newer engines due to break-in of the engine.”
Operators of the affected engines have to inspect the cranks to ensure the counterweight retaining rings were installed correctly. There had been several instances where the rings were put in incorrectly and the weights came off during flight. Continental spotted the fault and notified the FAA and its customers in February. The expanded AD took effect Wednesday (March 15).
