Best product to seal a coil?

[Frankn]

Here's the best thing if you want to seal the seams. Get some locktite thread sealer, the red type that dries, after it runs in. It dries to a hard rubber Constancy. It will not leak or crack. You can get it at a good auto parts store.

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[Iron Patch]

Can you show a pick of the coil and seam? Any decent modern coils are bullet proof, built with composite shells and superb rock- hard potting. No need for any sealing or covers in my opinion. Unless you are worried about scratches, then I say what 'digger says, a quality epoxy dip. Then you could polish your coil to a shiny sheen at the end of the season or whenever. Pretty expensive tho'.

I'll try to post a pic at some point. The early Minelab coils like I use had hundreds of pinhole type holes where they used epoxy on the seam. I figured that is what was causing the moisture issues as both my friend's coil and mine did not last at all. (Maybe 6 months) I have no idea why the holes were there, and seems like it was part of the process, but I feel better to seal the things.

 

[sniffer]

maybe they built them like that to ensure return customers?

 

[Iron Patch]

maybe they built them like that to ensure return customers?

It definitely seems odd. Both my current coils probably date back to that era so I'll check and see if they have the holes to show you what I'm talking about... and maybe someone will know why they are there. (what in the process did it - air etc)

 

[sniffer]

maybe they put it on and then filled the cavity with a sealer and that's where the excess was supposed to squeeze out

 

[mick56]

I have painted mine with pvc cement. Comes in a little metal can with an applicator attached to the lid.

 

[Frankn]

They might have been caused by expansion of air in the coil. Like sitting in a hot car. locktite has very good capillary action. Warm up the coil and place a drop on each hole. As the coil cools it will draw in the locktite.Heating it first will also drive out any moisture inside.

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[gleaner1]

Can you show a pick of the coil and seam? Any decent modern coils are bullet proof, built with composite shells and superb rock- hard potting. No need for any sealing or covers in my opinion. Unless you are worried about scratches, then I say what 'digger says, a quality epoxy dip. Then you could polish your coil to a shiny sheen at the end of the season or whenever. Pretty expensive tho'.

I'll try to post a pic at some point. The early Minelab coils like I use had hundreds of pinhole type holes where they used epoxy on the seam. I figured that is what was causing the moisture issues as both my friend's coil and mine did not last at all. (Maybe 6 months) I have no idea why the holes were there, and seems like it was part of the process, but I feel better to seal the things.

I was thinking Loctite Black Max. This is a top notch polymer-reinforced (strong micro fibers) gel-like super glue that will seal cracks very nicely. No pics IP? Are you talking those older white explorer coils? Are those hollow? Dipping in quality epoxy will work nicely as long as the cracks are not so big as to let epoxy start leaking inside.

 

[Ism]

One other suggestion ....spray on stone guard at auto store. Should be pretty tough, flexible and water resistant.

 

[Iron Patch]

First time I've looked in years, and guess they are air bubbles. There still seems to be a clear coating over these, but I'm not sure that was the case for my other old coil. My other one also had some small cracks too. Anyway, I'm going to slap something on as it can't hurt.

 

[gleaner1]

That coil is sealed for life with closed cell epoxy foam. Very good stuff going on. Foam epoxy is tough, light and waterproof. Even if the housings are cracked a bit, the coil is still good to go. It can't hurt so seal up the little cracks, I recommend hardware store five minute epoxy, it gets good and hard and it's cheap. I do not recommend an epoxy dip for that coil it's too nice and well built and there would be no benefit at all by dipping or spraying any type of crap on it at all. I can't resist to show some pics of my coil, a couple cracks between the shell and potting but it works good and I'm not worried too much about it. This coil has 14 plus years on it. Water can get into the cracks, but it can only go skin deep. It cant soak thru epoxy and modern composite materials, foam or otherwise. The manufacturers learned long ago that coils must be built tough.
This is a fisher coil that I use in the water a lot.