Bronze or bass seacock?
Posted by Ok-Western-18@reddit | sailing | View on Reddit | 40 comments
How can I tell if this is a bronze or brass thru hull seacock? If it's brass I want to replace it... If it's bronze I may keep it for another season.
fck_ptnskyi@reddit
With it having a teeny bit of green on it, I would say it's metal. And as it's kind of black, I would think Bronze. As said, scratch it - brass will be bright Is this a European boat? They use brass. If a US boat, much more likely to be bronze. If bronze and you've kept up with sacrificial anodes, you likely will never NEED to replace it...
FalseRegister@reddit
Wouldn't there have to be a wire from the bronze to the sacrificial for it to, well, sacrifice?
bill9896@reddit
You win the prize. An unbonded fitting is never protected by adding a zinc somewhere else. Anyone who thinks so just doesn’t understand electrochemistry. There must be an electrical connection between the protected part and the zinc. If not it is unprotected no matter how much zinc is on the boat.
keel_up2@reddit
You mean to say that the 475 lbs of zinc I keep under tarp in my truck isn't protecting the fittings on my boat?!!
bill9896@reddit
only through magic!
FalseRegister@reddit
:') As a recent boat owner still learning a thousand things, this is making my day
windoneforme@reddit
I'm not sure I'd say never. I've seen too many bronze parts on well maintained boats end up having some dezincing after 40 years. For anything below the water line I consider if I don't know the age then it needs to be replaced.
klaagmeaan@reddit
Bronze is an alloy of copper and tin, whereas brass is copper with zinc. So, dezincing on a bronze part is not possible since there is no zinc in it.
windoneforme@reddit
I'm not sure I'd say never. I've seen too many bronze parts on well maintained boats end up having some dezincing after 40 years. For anything below the water line I consider if I don't know the age then it needs to be replaced.
This, with no valve and no backing plate, I'd absolutely replace.
keel_up2@reddit
This isn't a seacock, but you might want to install one, depending on the kind of sailing you're doing. It looks like bronze to me, but you'd need to scrape it down a bit to be sure. If so, it can last ages if you keep up anodes on it.
Either way, you might consider putting in a seacock for peace of mind. 4200 is entirely suitable, unless you are doing extreme expeditions or heavy-weather sailing, which I'm guessing by this photo and question isn't the case.
Ok-Western-18@reddit (OP)
You're right it was bronze. I smacked them with hammers and sanded them down and they all dent and don't have any pink that I can see. I just want to do ICW.
J4pes@reddit
Unless it needs fixing you are wasting time and energy in an avenue that doesn’t need it imo. Boats have enough jobs without inventing new ones for fun
Ok-Western-18@reddit (OP)
I thought it would be considered a safety risk because it's below the water line and 40 year old plastic.
J4pes@reddit
Your money
Ok-Western-18@reddit (OP)
So you think there's no risk to sinking with this set up?
J4pes@reddit
For summer sailing, no
Ok-Western-18@reddit (OP)
I see. How about winter sailing?
keel_up2@reddit
Just ignore this one. If they aren't actually giving any reasons, their anonymous internet opinion is worthless.
J4pes@reddit
Whatever single sailing season a year your precious heart so desires
whyrumalwaysgone@reddit
It's bronze. Brass rusts, and there's no rust here. As others have said though, you need a valve if it's below the waterline. It's not in bad shape though, unless there's pink/pitting on the outside I wouldn't replace it.
daysailor70@reddit
Having been in the Marine business for decades, I will say that I have never seen a brass seacock. Not to say there are aren't low quality fitting out there, but brass is way too soft to be used for thru hulls. It is 100% bronze. Rub off the surface rust, if it isn't pink, it's OK.
bill9896@reddit
You haven’t worked on very many European boats. And brass is absolutely NOT too soft for seacocks. Where do you get that one? You do know that valves are made of brass all the time, right?
The EU has a rule that seacocks (and thruhull fittings) had to be “corrosion resistant”. Sounds really good, right? Except the definition of “corrosion resistant” was “suitable for purpose for five years”!!! Cheap brass seacocks met this standard, so many boatbuilders, lead by Group Beneteau, installed them. The European builders eventually got a bit smarter and switched to DZR Brass. A brass alloy resistant to dezinification. Better, but still BRASS not Bronze.
Ok-Western-18@reddit (OP)
My waste and sink outlet valves were brass ball valves.
TexasPirate_76@reddit
I can't stop giggling ... bass seacock
Capri2256@reddit
Definitely bass and most likely a largemouth bass.
pheitkemper@reddit
Whatever it is, the upper hose clamp looks to be installed above the tube. Making it be useless.
Ok-Western-18@reddit (OP)
Great eye
MWorld993@reddit
It must be thru-hull & seacock day on r/sailing.
As others have mentioned the lack of a valve and the deformed fiberglass are a concern. The website MarineHowTo.com has a good article on replacing thru-hulls and seacocks and a second on fabricating backing plates using G10. The author definitely has opinions but the articles are informative, the instructions easy to follow, and I’ve never had a bad result. They are also entertaining to read.
Unusual-External4230@reddit
His articles are generally good, but I do disagree wholly with his promotion of butyl tape over more traditional sealants like 4200. I've never seen someone apply it properly and not leak, the yard I used to be in saw a ton of boats in that had wet decks due to it and that echoes my own experience. Meanwhile we're removing 30 year old fittings still sealed well with 4200.
His info on seacocks/valves is very good, though.
Foolserrand376@reddit
its not a seacock....no valve, its just a thruhull.
don't see any corrosion on the mushroom threads could be a plastic mushroom with a metalic nut...
nothing wrong with plastic below the waterline, so long as its the right plastic.
Ok-Western-18@reddit (OP)
It would be from 1981 I think.
Foolserrand376@reddit
yeah its a bit old if plastic.
i've been slowly replacing all of my thru hulls and seacocks with the forespar marelon pro series. mostly for the reason that all the plywood backing plates are going to shit, and a few vavles have stopped working well.
Advnturman@reddit
It looks plastic. Scratch it a little
Ok-Western-18@reddit (OP)
Oh my, I think you might be right... Plastic, below the water line, no valve....
Advnturman@reddit
Yeah that looks like it might have been an instrument converted to something else. Should be replaced with a valve IMHO
The-Sixth-Dimension@reddit
Sea Bass
EuphoricAd5826@reddit
Regardless of what it is, it’s installed incorrectly and could be close to catastrophic failure. The leaking and warped fiberglass surrounding it are giveaways.
Free_Range_Lobster@reddit
plastic
ageofwant@reddit
Well if its a bass seacock check for rot from the head. But seriously just swap it with a composite, one thing less to worry about on a boat... Its unlikely to be brass, looks bronzy from the image. Give it a good brush down with a wire brush, if you see any pink you have seacock job in the morning.
ecjecj@reddit
if you polish/sand/file a part of it you could maybe tell by the color? bronze reddish brown, brass yellowish golden..