35TE vibration

[skye peak]

I've been chasing a resonant vibration in my 35TE sedan,1999, Cumminns single 450hp.

So far I've changed props, checked shaft runout (.002), cutlass is
tight, aligned engine and tightened motor mount to stringer brackets.

Now the yard is suggesting that I fair the trailing edge of the prop skeg to
eliminate hull cavitation.

Has anyone else experienced an ellusive vibration in a 35 hull, or tried
fairing the trailing edge of the skeg?

Thanks

[Tuxedo]

I've been chasing a resonant vibration in my 35TE sedan,1999, Cumminns single 450hp.

So far I've changed props, checked shaft runout (.002), cutlass is
tight, aligned engine and tightened motor mount to stringer brackets.

Now the yard is suggesting that I fair the trailing edge of the prop skeg to
eliminate hull cavitation.

Has anyone else experienced an ellusive vibration in a 35 hull, or tried
fairing the trailing edge of the skeg?

Thanks

I did on my 31, Tuxedo. The theory was that as the blades of the prop went behind the skeg, pressure on the blades dropped, then when they cleared, the pressure increased, causing a resonant vibration. At the same time, I added these Soundown damping tiles to the area above the prop inside the hull. Between these 2 fixes, all vibration was eliminated.

http://www.soundown.com/images/2.3/damp ... 01%20A.pdf

I'm not sure which of these fixes was most effective, but I'd try the Soundown solution first since it would be lots cheaper.

I have picture on an old computer I could dig up if you need them.