Need a better way to seal up additional anodes

alldodge

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Had trouble years ago with corrosion on my drive so I installed two additional anodes. The anodes came in a Merc kit and since then corrosion shows very little signs. When I installed, drilled 3/8 hole, passed the wires through, filled with silicone and secured with screws. I am seeing silicone is not the way to go. Even if it keeps the water out, water sitting in the bilge will slowly penetrate and soak into the transom wood core. What would you suggest as a better fix, 5200 or something else?

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Scott Danforth

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5200 is the sealant for below the water line. 4200 is the sealant for above the water line.
 

Rickmerrill

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Just so others reading this are clear on 4200, from the mfg...
Can be used above or below the waterline; approximately half the strength of 3M's 5200, which allows for eventual dissasembly of parts.
The "eventual disassembly of parts" is the reason I favor it.
 

Arawak

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When I put holes in the transom I over drill them, fill with epoxy-based PB, and drill a smaller hole after it's cured. Then I'd seal the wires with 5200 of silicone or whatever you prefer. You may get a little water in your bilge if the wires work loose, but you will not create a rotten spot.
 

alldodge

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When I put holes in the transom I over drill them, fill with epoxy-based PB, and drill a smaller hole after it's cured. Then I'd seal the wires with 5200 of silicone or whatever you prefer. You may get a little water in your bilge if the wires work loose, but you will not create a rotten spot.

Very good point, was thinking my self of using resin and redrilling the hole. Will give it some thought
 

kcassells

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Yup...thats the way to do it. Just make sure the 5200 is cured before you cover the holes with plates/hardware.
 

alldodge

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Yup...thats the way to do it. Just make sure the 5200 is cured before you cover the holes with plates/hardware.

I'd have to ask how to do that. The anode has a 1/4 long piece of plastic which extends into the hole, the wire comes out of it. H\Don't see how the hole can be prepared, add 5200 and let cure and still get the anode back on the boat? 1st Pic

My thought is to get the hole prepared, then put some 5200 on the inside of the anode and in the hole. Secure the anode, then go in the inside and put some more 5200 on the inside and let cure
 

alldodge

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Well with all the ideas I dug into reading further into the issue. Found some very good articles at BoatUS on sealants. With this being in the bilge there is a good possibility that what ever I use will come in contact with solvents, gas, antifreeze and other chemicals. The sealant used should be resistive to the stuff which could come be their. The wire that comes from the anodes I believe is Teflon, which means next to nothing will stick to it, but the anode housing is plastic. Current plan will be to drill out the holes to 1/2 inch and fill with Marine Tex. Then drill 3/8 hole thru the epoxy, clean with Acetone and use 3M 4000. Will sand and clean outer hull larger then the out surface of the anodes. Screw the anodes in place, wipe down with Acetone then use 5200 around the outer edge of the anode and cover screws. Sure appreciate the help, did I miss anything?

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alldodge

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Started cleaning the silicone off the anode, and I forgot all about it had an O-ring on the back. The silicone and O-ring was doing their job keeping water out, all moisture getting in was from inside the bilge

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alldodge

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Drilled the hole out to 1/2 inch and while the wood is solid it is a bit damp. Started taking a heat gun to it to dry it out. Since this is a vertical area I thing stuff like git rot would work down but not up. Still looks though drying it out should work from what I'm seeing
 

fhhuber

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Unfortunately with fiberglass encased wood, once water gets in the rot is going to start and you can't prevent it, you can only slow it down. Its a practical impossiblility to dry it out. And even if you get the wood dry the rot process will have started.

Might take just a few years... Might take a very long time.
 

alldodge

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Unfortunately with fiberglass encased wood, once water gets in the rot is going to start and you can't prevent it, you can only slow it down. Its a practical impossiblility to dry it out. And even if you get the wood dry the rot process will have started.

Might take just a few years... Might take a very long time.

Well then I guess we all should just stop trying to fix our hulls :rolleyes:
 

Arawak

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Well then I guess we all should just stop trying to fix our hulls

I think what he's saying is that your transom is compromised, and drying it out will not put it back to new. You might buy yourself a few more years, but your transom is dying.

So your choice is to put in a new transom now, or patch it up and put in a new transom in X years. X might be 2 or 10, but my guess would be somewhere in between.

Remember, we're just trying to help you make the decision that suits you. It's your choice how you proceed.
 

Woodonglass

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Uhmmm, Wet wood, and rotting wood are, in fact Two very distinct and different things. If in fact the OP's transom wood is just wet and NOT started in on the decaying process then it CAN be dried out and it will NOT rot in the future. I would suggest he spray it with some antifreeze and that will greatly aid in killing any spores etc that might cause decay and will also enhance the drying of the wood. All of the other methods described for sealing the wood prior to installing the anodes are good, IMHO!!!
 

alldodge

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Uhmmm, Wet wood, and rotting wood are, in fact Two very distinct and different things. If in fact the OP's transom wood is just wet and NOT started in on the decaying process then it CAN be dried out and it will NOT rot in the future. I would suggest he spray it with some antifreeze and that will greatly aid in killing any spores etc that might cause decay and will also enhance the drying of the wood. All of the other methods described for sealing the wood prior to installing the anodes are good, IMHO!!!

Thanks, yes it is barely damp. Prior to drilling the hole bigger I tried to dig some wood out with a small screw drive, next to no luck. After drilling from 3/8 to 1/2 I can see the wood fibers drilled out are a bit damp but not much. What is the anti freeze your talking about, ethylene glycol or the pink stuff? Thought of using git rot but being vertical it would be hard on the top.
 
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