I have a Hunter 1983 great sailing vessel but I am getting reports of very bad electroylisis on the keel. Opened the panel to look at the wiring at the plate and bolt for the keel where the bildge pump is. There are 3 black wires. 2 are connected under the plate for the keel where the bolt is and one is dangling free. Looked in my manual, but no outline of where the 3 wires go. I afraid that the one that is frailed and not connected is a ground and may be the source of the electrolysis. Sorry if I am not being very clear. I had the person who takes care of my Hunter look at the wires, but he was not sure if the 3rd black wiire that is dangling is a groung wire for the keel. Many thanks, Craig
Hunter bad electrolysis 1983 34
- Thread starter cjgrabell
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If your boat is indeed a H34 ( not a 34.5 as it says under your name) I am surprised that your Cast iron keel is showing electrolysis. Are you sure it isn't just that old, never sleeping enemy- rust? There are grounding wires that go to the keel bolts (for lightning), I cant remember how many and the boat is still up under cover :cry:
Craig...
given Richard's comment about the keel, first be sure the "electrolysis" issue isn't just rust.
There should be a zinc egg on the prop shaft between the strut and hull bottom. If there isn't one or the one there looks like it's all chewed up, then you do in all probability have an electrolysis problem.
Most times that is a shore-power related issue. Keep the shore power cord unplugged when away from the boat. If you must keep it connected, install an isolation transformer to keep your boat isolated from being in a ground loop for stray current that could actually be coming from one of your neighbors in the slip on either side of you.
The "black wires" in your bilge are not related to this issue normally. They are probably a part of your rigging grounding system for lightning strike protection. A "dangling" wire sounds unusual. Get yourself an inexpensive digital voltmeter ($20-$30 at HD) and use it to trace what that wire is connected to.
From here it gets a lot more technical and the hiring of a marine-certified electrician wouldn't be a bad idea if you're not up to snuff on the details of boat 12 volt and 120 volt power systems.
given Richard's comment about the keel, first be sure the "electrolysis" issue isn't just rust.
There should be a zinc egg on the prop shaft between the strut and hull bottom. If there isn't one or the one there looks like it's all chewed up, then you do in all probability have an electrolysis problem.
Most times that is a shore-power related issue. Keep the shore power cord unplugged when away from the boat. If you must keep it connected, install an isolation transformer to keep your boat isolated from being in a ground loop for stray current that could actually be coming from one of your neighbors in the slip on either side of you.
The "black wires" in your bilge are not related to this issue normally. They are probably a part of your rigging grounding system for lightning strike protection. A "dangling" wire sounds unusual. Get yourself an inexpensive digital voltmeter ($20-$30 at HD) and use it to trace what that wire is connected to.
From here it gets a lot more technical and the hiring of a marine-certified electrician wouldn't be a bad idea if you're not up to snuff on the details of boat 12 volt and 120 volt power systems.
Many thanks for the good advice. I noticed that there is also a power cord I can purchase to identify current. The person who takes care of my Humter purchased a sacraficial zinc line along with the zinc, just replaced on the shaft. The sacraficial zinc line has a clip to attach to the boat for the reduction of electroylisis to the keel. Would any of the back stay lines be appropriatte to clip this to for redirection of current. Very grateful for the responses.
Craig
Craig
Craig...
the most common form those clip-on sacrificial zincs take looks like a big fish on the end of a stranded cable. Yes, their intent is to protect your boat the same as the shaft zinc. Whatever you clip it to, be sure that that piece of metal is a part of the ground system. The backstay could serve as a connection point. Just don't forget to unhook it before getting under way!
The consequence of electrolysis isn't a problem with the keel. The much more common and serious attack point are your bronze thru-hulls. If electrolysis weakens them, you could loose the boat if one breaks off under way. Until you ultimately solve this probelm, get yourself some of those wooden tapered pegs and tape one of the correct size for the thru-hull's inside diameter to each through hull hose. Get a good rubber or plastic head mallet and keep it in a handy spot (under the galley sink for instance) where you can get at it in case the worst happens.
Solving the electrolysis problem doesn't negate the need for the wooden plugs, just makes them slightly less critical to have! Get some!
the most common form those clip-on sacrificial zincs take looks like a big fish on the end of a stranded cable. Yes, their intent is to protect your boat the same as the shaft zinc. Whatever you clip it to, be sure that that piece of metal is a part of the ground system. The backstay could serve as a connection point. Just don't forget to unhook it before getting under way!
The consequence of electrolysis isn't a problem with the keel. The much more common and serious attack point are your bronze thru-hulls. If electrolysis weakens them, you could loose the boat if one breaks off under way. Until you ultimately solve this probelm, get yourself some of those wooden tapered pegs and tape one of the correct size for the thru-hull's inside diameter to each through hull hose. Get a good rubber or plastic head mallet and keep it in a handy spot (under the galley sink for instance) where you can get at it in case the worst happens.
Solving the electrolysis problem doesn't negate the need for the wooden plugs, just makes them slightly less critical to have! Get some!
My 34 has 4 things in the cubby above the engine locker in the companionway:
Lighter (for the stern rail grill)
Winch handles
Flare kit
Kit with various wooden pegs and mallet
Lighter (for the stern rail grill)
Winch handles
Flare kit
Kit with various wooden pegs and mallet
ZDS: All my "critical use" stuff...
(pegs, mallet, spare flares, etc.) are in the knee level cabinet at the nav station. The flare gun canister hangs under the nav table. Winch handles ride on the aft cabin shelf and the lighter in a galley drawer.
The cubby under the companionway holds my "hardware store": a number of plastic divider boxes with stainless hardware, electrical connectors, fuses, bulbs, cotter pins/rings, all other sorts of small stuff.
(pegs, mallet, spare flares, etc.) are in the knee level cabinet at the nav station. The flare gun canister hangs under the nav table. Winch handles ride on the aft cabin shelf and the lighter in a galley drawer.
The cubby under the companionway holds my "hardware store": a number of plastic divider boxes with stainless hardware, electrical connectors, fuses, bulbs, cotter pins/rings, all other sorts of small stuff.
Re: ZDS: All my "critical use" stuff...
Dear Dan:
Can I loosen that center bolt that is atteched to the keel enough so that I can move the plate and get to the ground wires. Am I at risk of loosening the keel. My Hunter is a 34.5. the plate currently covers the gound wires. don,t want to watch the lead keel drop to the bottom of the ocean. What are the wooden pegs used for. I noticed that I do have some on my Hunter.
Many thanks, Craig
Dear Dan:
Can I loosen that center bolt that is atteched to the keel enough so that I can move the plate and get to the ground wires. Am I at risk of loosening the keel. My Hunter is a 34.5. the plate currently covers the gound wires. don,t want to watch the lead keel drop to the bottom of the ocean. What are the wooden pegs used for. I noticed that I do have some on my Hunter.
Many thanks, Craig
Craig...
the wire wasn't trapped under the keel plate by accident. The wire was probably stripped so that it makes a good grounding contact with the plate when it's compressed onto it by the keel bolt. Why do you want to remove it?
As the bolts in the bilge are the center plate, the keel probably won't fall off if it's loosened as there are others fore and aft holding it on. At issue will be whether you can loosen it at all without breaking the bolt off in the keel, given the boat's age. If you don't absolutely need to do it, don't.
The wooden pegs are tapered to fit in the thru-hull pipe if the valve breaks off or a hose comes off and you can't close the valve. There're handy for keeping your feet, knees, butt, etc. from getting wet.
the wire wasn't trapped under the keel plate by accident. The wire was probably stripped so that it makes a good grounding contact with the plate when it's compressed onto it by the keel bolt. Why do you want to remove it?
As the bolts in the bilge are the center plate, the keel probably won't fall off if it's loosened as there are others fore and aft holding it on. At issue will be whether you can loosen it at all without breaking the bolt off in the keel, given the boat's age. If you don't absolutely need to do it, don't.
The wooden pegs are tapered to fit in the thru-hull pipe if the valve breaks off or a hose comes off and you can't close the valve. There're handy for keeping your feet, knees, butt, etc. from getting wet.
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