J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Replacing Propeller Shaft 7/8 vs 1 Inch

David - Rhapsody has a 1" shaft. 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.

So, it is major work to upgrade to a 1" shaft. I'd try 3/4" for now and see if you have a vibration problem. If not, you're set. If so, consider this the 1st item on the list next time you haul the boat. Just remember you'll need a new shaft seal and coupling flange too. It's only money....

Bill