What is Causing This Blue Corrosion on the Seacocks?

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MHBsailor
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What is Causing This Blue Corrosion on the Seacocks?

Post by MHBsailor »

The previous owner had his yard replace the two Spartan cockpit drain seacocks several years ago with what I was told were ball valve seacocks. Already they've accumulated an unsightly patina from what I'm presuming is saltwater-induced corrosion. The blue makes me suspect that one of the metals is copper. Is this a safety issue or just cosmetic? The seacocks function fine. Is it possible to treat it with something to remove the patina? Or should I plan on going back to Spartan seacocks when they are no longer functional? Thanks! JD
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John Stone
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by John Stone »

NarragansettSailor wrote:The previous owner had his yard replace the two Spartan cockpit drain seacocks several years ago with what I was told were ball valve seacocks. Already they've accumulated an unsightly patina from what I'm presuming is saltwater-induced corrosion. The blue makes me suspect that one of the metals is copper. Is this a safety issue or just cosmetic? The seacocks function fine. Is it possible to treat it with something to remove the patina? Or should I plan on going back to Spartan seacocks when they are no longer functional? Thanks! JD
Copper is the primary element in bronze. So that’s good. I love the blue patina on exposed bronze on deck. What it means there though is saltwater is weeping down on the seacock. Tighten the hose clamps. You can knock the patina off with a wire brush.

It’s probably OK but I am not thrilled with the installation of the seacocks in the photo. There should be two hose clamps on those seacocks. There should be security bolts from the hull through the seacock base. And the plywood pad should be sealed with epoxy. But I have seen plenty of seacocks without the bolts and backing plates made of untreated plywood last for decades. It’s just not done correctly.

It’s typical boatyard work. It’s why I think informed boat owners who want to do a good job almost always do a better job than the so called experts at boatyards who demand outrageous fees for mediocre work. It’s just a personal gripe of mine. In other words, if you have some time to devote, fear not, you will do a better job on your own boat than the “pros from Dover.” Just saying....
MHBsailor
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by MHBsailor »

Thanks for the most helpful observations John! I think that you should set up a site so that I can pay for your advice. Quite frankly, I'm surprised at the questionable workmanship that you identified, given the reputation of the yard that did the work. Forgot to mention that yes, I am planning to double-up on the stainless steel clamps after replacing both hoses before launch next Spring. What kind of metal should the security bolts and wire be made of to be compatible with the bronze seacocks to prevent galvanic corrosion issues? And where should the plywood backing pad be sealed with epoxy? How about using G10 or some other synthetic material instead of wood? JD
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John Stone
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by John Stone »

NarragansettSailor wrote:Thanks for the most helpful observations John! I think that you should set up a site so that I can pay for your advice. Quite frankly, I'm surprised at the questionable workmanship that you identified, given the reputation of the yard that did the work. Forgot to mention that yes, I am planning to double-up on the stainless steel clamps after replacing both hoses before launch next Spring. What kind of metal should the security bolts and wire be made of to be compatible with the bronze seacocks to prevent galvanic corrosion issues? And where should the plywood backing pad be sealed with epoxy? How about using G10 or some other synthetic material instead of wood? JD

Nah. Paying it forward. Bronze flathead. They are “probably” 1/4-20. You will want bronze washers and split washers and nuts. G10 is the best solution.

My intent was to point it out without causing you worry. You can almost certainly sail it as is but it’s not right. It’s actually not a hard project. Kind of fun. And the skills build one on top of the other.

Mainsail has a great how to site a lot of folks use. I have used it too. Very professional, well researched and documented.

https://marinehowto.com/

Here is how I did it. Scroll down about 2/3 of the way. http://www.farreachvoyages.com/projects ... rline.html

Good luck.
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by Jim Walsh »

Those are Buck Algonquin bronze ball valves which are good quality, but they should have been fastened to the hull and the hoses double clamped as John stated. It’s hard to believe a professional would take credit for that installation. Not imminently dangerous but apparently he had no professional pride in his work. Won’t take too much effort to do it right. Good luck.
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arch007
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Re: What is Causing this white corrosion on the Seacocks?

Post by arch007 »

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Not to hijack this thread but what is causing this white stuff on my sea cocks ?
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Steve Laume
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by Steve Laume »

John had great advise as usual but I don't think the weeping is occurring from the hose clamps. If you look carefully, there is no staining, originating at the hoses. It looks like a bit of weeping at the packing gland at the handle. Yes, do add another clamp but don't expect to end the staining that way. Clean it off if it bothers you and don't worry about it. The Spartan valves are going to stain at some point as well and it will cost you a bunch of money to find out.

I agree with everything said about yard work. The point is, most of those guys are good about getting things done. To really do the job right would have meant a whole lot more work. Replacing the backing plates would have added a great deal of cost. An extra clamp would not have been too much to ask. Professional work is always about balancing costs and results. If cost is no object, you can expect some fine results.
Most people are not willing to pay for the time it would take to do every job in the best way possible, Steve.
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by JD-MDR »

Maybe I'm lucky but I've had good luck with the boatyards I've used Alimitos Bay, Long Beach CA, San Francisco Boatworks, and Ventura boatyard and also Windward Boatyard at Marina Del Rey and Ala Wai boatyard in Honolulu. Yes they are expensive but plumbers and other technicians are charging the same. They don't have nearly the investment and overhead that boatyards have. I just have to work about two hours for every hour I pay them. I guess I should rephrase having "good luck" at boatyards with" I haven't had any bad experiences"
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by appletim1 »

I'd start fresh with properly installed, used Spartan seacocks, with G10 backing plates, new hose and 4 marine grade non perforated hose clamps. That way, with routine maintenance, the issue won't happen again for the next 40 years. It will take time and will cost money, but peace of mind is priceless.
MHBsailor
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by MHBsailor »

Thanks everyone for your advice!

Tim - Where did you get the hoses for Serenity from? Congrats on moving up to your 27 :D

JD
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by appletim1 »

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MHBsailor
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Re: What is Causing This Blue Corrosion on the Seacocks?

Post by MHBsailor »

Thanks Tim - so true! What brand of drain hose did you purchase for your former CD22? I recall that it used to be mentioned on one of your older WordPress pages that's no longer there? I looked up the manufacturer and was impressed, but I lost the link to their website. Thanks again. JD
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