Re: High pitch flutter sound
Group....I need your help. I've got a 261 Four Winns Liberator with twin 460 Cobra engines. When I'm running the boat at moderate and high speed I hear a high pitch fluttering sound. A friend of mine who has a Baja told me it was the exhausts. It's a constant and not particularly loud noise. I don't hear it at low rpms.
Howdy,
You flying that Lib or are you flying something else!!
It's VERY difficult to know what you mean by "high-pitch Fluttering" without hearing it and I don't think a cell phone or camera video will reproduce the sound good enough for any of us to even make a guess!
It's very possible that the exhaust shutters (Exhaust seal) could be making noise. But you would have to have thru-prop exhaust. I am pretty sure that most of the 261's were thru-hull.
Unless you can find a problem with your flame arresters, You're going to have to have someone drive it while you look and eliminate possible sources.
Does it change with RPM and have you varied engine RPM separately?
Post pictures. I love to see 261's
Regards,
Rick
