«I forgot to mention that about 5 years ago I checked the grounding strap that is connected to all of the bonding in the engine room. It is in the wet bilge and is made of flimsy copper. Mine was almost eaten through. I replaced with a 1/8 inch thick copper flat stock.
If your zincs are getting eaten up this might be the problem. To change the grounding bar you need to get the bilge dry and have about 3 12 inch extensions for a socket wrench to remove the keel bolt that it is connected to bar.»
Our zincs are not getting eaten up, but our diver reported this week that our keel shows "veins" of "orange" material "erupting out" that looked, in his opinion, "like electrolysis" (words in quotes his).
I dismissed this all week long thinking that the keel bolts were connected to nothing, but now am curious. And keen.
