The FAA has issued an airworthiness directive calling for crankshaft replacement in certain 360 and 540 engines built or with crankshafts replaced after March 1, 1999. As AOPA first told you in July, this AD affects some 1,100 aircraft, in models ranging from Aero Commanders and Aerostars to Socata Trinidads. Many of the affected aircraft are Robinson helicopters and late-model Cessna 182s.
You'll need to know your engine model, engine serial number, date of manufacture, and horsepower rating to determine if your engine is affected (see Lycoming's service bulletin).
"Lycoming tells AOPA that some 238 engines have already been sent to the factory in response to the earlier service bulletin, and the company has completed repairs on about half of them already," said Luis Gutierrez, AOPA director of regulatory and certification policy. "The company has been in direct contact with the owners of more than 660 of the affected aircraft."
This is a continuation of the problem that affected high-powered, large-bore turbocharged Lycomings three years ago. Those crankshafts weren't strong enough (why is still a matter under litigation between Lycoming and the crankshaft supplier), and now Lycoming has determined that crankshafts made with the same process used in lower-powered engines could also have problems.
Lycoming will pay for replacing the crankshaft and shipping the engine to and from Lycoming's Williamsport, Pennsylvania, factory to accomplish the work. The company will also pay a reasonable amount for the labor involved to remove and reinstall the engine.
"Lycoming officials told us that they have enough new crankshafts on hand to repair all affected engines," said Gutierrez. "They expect to complete up to 15 engines a day with a 10-day turnaround from the time the engine arrives on their dock."
The AD becomes effective October 21 and calls for compliance within the next 50 hours or 6 months, whichever comes first. See the Lycoming service bulletin, which lists the affected engines and crankshafts.
September 19, 2005