Pink seacock

[Mafi]

Dear members,
Getting a bit frustrated here. Bought my lovely Bav 33 cruiser 3 years ago, a 2006 model, had survey done which pointed out pink colour on the hull fitting seacocks and recommended replacing. Duly done. Year 2 had the carrenage/ antifouling done professionally and they reported that the outer seacock fittings were pink and did I want to replace. I of course did. This year I am doing the carenage/ antifouling myself and lo and behold, pink fittings.
Am I being over cautious in replacing again? This never happened on my previous boats. Any advice would be extremely welcome.

[Yngmar]

Just install TruDesign ones and no more pink problems

[jeffatoms2]

A quick Google search confirmed my thoughts...

"If it is bright yellow when scraped, all is well, but if it is pinkish, it means that the zinc in the metal has started to leak away by electrolytic corrosion. The seacock should be changed without delay if found to be corroded, as the metal will be brittle and might break off if the handle."

This can be cause by stray current in the marina, actually in the water, where your boat is docked.  I'd play it safe and check for this problem and consider installing an isolator.

[symphony2]

Sounds like the yard who replaced them used plain brass instead of DZR. Pink on the surface of the through hull is quite common but does not necessarily mean that the fitting is in any danger of failing. scrape it away and expect you will get to shiny brass very quickly. Just about all the mass producers including Bavaria use plain brass fittings but there is no sign of an epidemic of failures. Long term - we are talking many years there is a possibility of dezincification caused by galvanic action - not electrolytic), usually in the threads making the fitting brittle. However rarely results in failure in normal use but may break if subject to a heavy load or blow by a hammer!

If you are worried about them replace with either DZR or composite (Tru Design). If you do replace suggest you cut through the fitting and I will be amazed if it is anything other than bright shiny yellow metal!

[Lazy Pelican]

As Yngmar says- fit TruDesign.

[Mafi]

Many thanks for the swift suggestions. Just had a little scrape and there is shiny yellow beneath the pink. So I will leave them for the minute, keep an eye, and replace with Trudesign in due course, albeit in the face of complete opposition from the guy who normally helps me! Oddly enough it is only on the starboard side. The port fitting is fine.

Thank you all again.

[Yngmar]

So the guy who makes money from replacing your seacocks every two years is against replacing them with ones that never need replacing again?

Very strange and completely inexplicable! 

[symphony2]

Don't be too hard on them. Plain brass fittings have been used for decades by European builders (including Bavaria) and there has yet to be an epidemic of boats sinking. This is not to deny that they can dezincify over time - many years but it rarely results in failure as they are under very little stress in their normal function and even dezincified through hulls are plenty strong enough until you apply force against them such as hitting with a hammer.

In another life I used to introduce students to the notion of moral panic, and this would make an excellent example along with the witches in the Orkneys and the child sex abuse in Rochdale.

Of course now that superior metal fittings (DZR) and composite are available at more sensible prices compared with bronze it makes sense to fit them at replacement time.

As an aside I had to bite my tongue when the surveyor for the buyer of my 2015 B33 reported the same pinkness and I took the line of least resistance and adjusted the price, knowing full well there was nothing wrong with them and it was unlikely that the buyer would replace them anyway. Add moral blackmail to moral panic - but there was £90k at stake and he was an almost perfect buyer.