shore power, zincs

[Norton]

I have a 74 O 23 and the battery charger (a Readi-Amp) recently fried my battery. I have only been using shore power for about 4 months. The charger may be as old as the boat and I am assuming it just went bad. While researching the cost of a new charger I started wondering about zincs or the lack of them on my boat. On a 74 the cast iron keel is bolted on and not encapsulated. I don't know if the keel has any contact with dissimilar metals. Did O'day put zincs on these boats? Do I need zincs to protect my keel or are they unnecessary?

 

[DaveM10278]

If you are in salt water, it can do no harm!

Rob, I am assuming that your boat's mast, stays, etc is grounded via the keel like mine ( an 1987 O'Day 322) to protect you in a lightning strike. Look for a green wire on one of your keel bolts. You can get external zinc at a marine store for your boat and connect it to a stay and that should help protect anything metal connected via the boat's grounding. You may also want to look into a multi-stage charger for your battery. Best of luck.Dave

 

[Norton]

I think my mast is ungrounded

I do not think my mast is grounded to the keel, although I might be wrong. The only wires coming off the mast are the vhf antennae and the anchor light. Maybe in a roundabout way the mast is grounded through my electrical system, but the shielding on the cables would probably prevent a good ground, and I don't know if the electrical system is grounded to the keel. I guess they could have run a ground from one of the chainplates, but I have not seen it. I'll have to look again more closely. I thought that zincs were placed underwater to be in contact with metal and seawater, if I can ground the mast and protect the boat with a zinc on the stay it would make inspecting and replacing the zinc very easy. Obviously I am not an electrical expert so any input is appreciated, thanks.

 

[DaveM10278]

RE: If you are in salt water, it can do no harm

Rob, You are right about the theory that the zinc should touch metal and saltwater. I assumed that your stay would be metal that connects to the metal mast and metal chainplate. Somewhere I also assume that they are connected to the boats electrical ground. On my boat there is an electrical ground wire in the bilge going to the keel. All of the thru hulls that are metal are also grounded. Check your bilge next time you are on the boat. Best of luck.Dave

 

[Norton]

Going to the boat this weekend

Dave,Thanks for the input. I am going to give the boat a good going over this weekend. If the boat is not grounded through the keel, I think stray electricity should be at a minimum from my boat and the major issues would be with my dockmates and the common ground through the shorepower?