Textron Lycoming issued a mandatory service bulletin earlier this week calling for crankshaft replacement in certain 360 and 540 engines built or with crankshafts replaced after March 1, 1999. Some 1,100 aircraft are affected, the majority being Robinson helicopters, followed by late-model Cessna 182s, some Piper models, and a scattering of other aircraft, including Commander 112s. (However, the AOPA Sweepstakes Countdown Commander is not affected.) 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).
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.
While a service bulletin isn't mandatory for Part 91 operators, it's likely that the FAA will issue an airworthiness directive that will be similar to the service bulletin.
AOPA has been in contact with Lycoming to see if the company can adequately meet the demand for replacement crankshafts.
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 Luis Gutierrez, AOPA director of regulatory and certification policy. "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 service bulletin calls for compliance within the next 50 hours or six months, whichever comes first. See the service bulletin and the list of affected engines and crankshafts.
[See also AOPA's issue brief.]
July 14, 2005