I have two questions as I am trying to understand bonding - first, with the boat out of the water, what is the best way to troubleshoot a possible bonding or grounding issue? Second, what do I really need to have bonded? Our friend's Jeanneau has no bonding at all.
This is driven by the fact I believe I have an issue with some stray current on our 1983 O'Day 34. The last couple of seasons I have noticed an area at the keel to stub where there is discoloration on my VC-17 copper bottom paint on both sides of the keel at the same location fore and aft. I also realized that I have the same issue to a lesser degree at each of the metal thru-hulls and at the metal strainer for the engine water intake. The common denominator is that these items are all connected with a #10 bare copper bonding wire. The affected area along the keel is at the bolt the bonding wire is attached to. Also on the bonding circuit are the mast, engine, forestay and backstay straps. I use a magnesium anode on the stainless prop shaft as we are in fresh water, and it is usually about 1/3 gone in a season. The bronze prop and strut may be seeing some galvanic corrosion, almost like they were sanded with course sandpaper, not really pitted so maybe it is electrolysis? We are on a mooring so stray dock current or another boat don't seem likely to be part of the issue.
This is driven by the fact I believe I have an issue with some stray current on our 1983 O'Day 34. The last couple of seasons I have noticed an area at the keel to stub where there is discoloration on my VC-17 copper bottom paint on both sides of the keel at the same location fore and aft. I also realized that I have the same issue to a lesser degree at each of the metal thru-hulls and at the metal strainer for the engine water intake. The common denominator is that these items are all connected with a #10 bare copper bonding wire. The affected area along the keel is at the bolt the bonding wire is attached to. Also on the bonding circuit are the mast, engine, forestay and backstay straps. I use a magnesium anode on the stainless prop shaft as we are in fresh water, and it is usually about 1/3 gone in a season. The bronze prop and strut may be seeing some galvanic corrosion, almost like they were sanded with course sandpaper, not really pitted so maybe it is electrolysis? We are on a mooring so stray dock current or another boat don't seem likely to be part of the issue.
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