Below is an excerpt from a previous post I made a while back. Do you have a 1" shaft? It may have been changed, thus the line around the strut mounting plate.
I met the original owner this summer and he indicated the boat (Hull #348 originally named Tontine in 1981) was built with a 3/4" shaft, but he had heard of other owners complaining of "shaft whip" vibration, so he convinced Everett Pearson to change the shaft. He said that the day before he took delivery that TPI cut out the old strut, and glassed in a new one. This explains why I have a 9" square seam line above the strut inside.
I ground down the crack at the seem and found they were cosmetic. I layed up some resin and glass cloth to cover the crack just in case.
[This message has been edited by Rhapsody #348 (edited 09-29-2008).]