27 27.94 N 080 19.69 W
We got a lot of work done the first day. We got the boat up on the hard. I got the propeller and hub off the shaft. I removed the shaft log. I unbolted the shaft and removed it from the boat. That's the good news.
The bad news is that I see no evidence to support the theory that a vibrating shaft log was the cause of the problem. With the log removed, the shaft appears to stick right through the middle of the hole. That indicates that engine alignment was nearly perfect. However, I have to recheck it with the flexible coupler removed because the flexibilty allows the shaft to droop a bit. The shaft log hole, and the bolt holes all appear normal, not elongated.
That puts us in caution mode. The worst thing we could do would be to put everything back together without solving the root cause. Therefore, I'm sending the propeller and the shaft away to a prop house to check for straightness and balance.
We also discovered a new problem. I have a copper plate on the hull that forms our lightning ground. It is separate from the Dynaplate that is the electrical ground for the boat. The bolts and screws holding the copper plate in place appear to be eroding away due to galvanic action. I'll replace them with stainless which is more noble (less noble?) than copper.
I'm getting great advice from blog readers. Two readers suggest I replace the bronze log with a fiberglass shaft tube. However, two people in the yard advise the opposite. Situation normal, conflicting advice. I'm not decided yet which to do.
Libby is cleaning and waxing the hull.
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Stainless really doesn't like environments without oxygen. I suggest silicon bronze which is less likely to set up a corrosion issue for you, but you ought to check with a metalurgist, not me.
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