Bristol 30 - Shaft spins, but no propulsion!?
My prop shaft is turning, but I barely have any propulsion ... here's what happened:
A couple weeks ago I bought a 1976 Bristol 30. Although I have a decent amount of coastal cruising experience, this is the first cruiser I have owned. The boat has been in the water at a slip in Quincy, MA all summer, and not sailed once by the owner except to get her in the water from winter storage in Gloucester. She is mostly in good shape, with some cosmetic work to keep me busy this winter. A new 18hp Yanmar was installed in 2001.
I went to the dock with a couple friends today to do a test cruise before sailing home for winter storage. As we pulled away from the dock, I suddenly realized I barely had any propulsion considering the speed the engine was running at. Without much propulsion, I hardly had any control at the helm. We managed to get about 10 feet away from the dock, and my stern turned into the light breeze in the harbor. Acting quickly to separate us from the other boats at the dock, I put the throttle down hard in reverse. It seemed that this was only enough to counter the breeze, at we didn't move for what seemed like an eternity. Everything raced through my mind:
- Am I stuck in mud already? There are bigger S/Vs in this marina with deeper draft, AND it is high tide (over 8 ft higher than the low at this point)
- Is the prop not turning? Engine and prop shaft were running fast an smooth, AND I am seeing lots of churning in the water (I should also mention some bottom vegetation and a little oil was in the water)
Finally by shifting forward and reverse and turning the helm to the stops, I was able to 'drift' back toward the dock, and tie up. We investigated everything we could from inside the engine compartment and above the water, and I am at a loss. All I can imagine is that the prop completely corroded away and fell off, or the key way is somehow slipping and the shaft is just spinning within the prop. Any other hypothesis would be welcome.
Finally, I have a good friend with scuba gear willing to take a closer look this weekend, but we don't know how feasible it would be to replace the prop while in the water. A detailed assembly of how the prop fits to the shaft on this type of sloop, or a list of spare parts or tools would be very valuable. Any advice or links in this direction would be most appreciated.
1976 Bristol 30, Mariah