Thru hull valves

[Macmunch]

Hi guys, long time voyeur on the website, first time post,
I'm stuck in Antigua working on my boat, been on the hard for 18 months getting ready to splash, I have a 43' Benetaeu Oceanis, she's and old girl but has great bones?

My question busy doing the valves on the thru hull fittings, have purchased Groco full port bronze valves? However American valves not compable with European threads? I can source locally Budget Marine here in Antigua a valve manufacturer called Siral? It's made in Italy so threads comparable however looking at the specs for there marine application they are made of Brass the code on the valve is CW617N but cannot find a designation that tells me if it's suitable? Have been told stay well away from Brass in the marine environment?
My other option would be to retain the Croco valves and change out the thru hull fittings to suit the US threads?
Thanks guys all information in this regard will be much appreciated, cheers all and stay safe, have to say Antigua not a bad place to be hiding from Covid?
Cheers
Regards.

John

[Dockhead]

Unless you are sure that the skin fittings (through hull mushroom fittings) are bronze and in perfect condition, you should change them with the valves. Beneteau were using brass underwater fittings for some time -- be sure you don't have those. If in doubt, just change them. It's a lot of work, but what price knowing that your boat won't suddenly sink?

Don't even consider using brass. Good way to sink your boat. DZR brass is somewhat OK but I wouldn't use those, either -- insist on real 85-5-5-5 bronze, which is the right material for underwater fittings.

I would not use American skin fittings if I were you. Big difference between American ones and European ones is that the American ones aren't compatible with each other. Yes, incredible, but true -- you need an adapter to use American skin fittings with American size ball valves -- I'm not kidding. Read Marinehowto website for more information.

Whereas the Rest-of-The-World sizes, which are BPT and BPS, DO work with one another. So I would stick with those if I were you. If Groco make them in BPT/BPS, those are great, otherwise try to find Maestrini Italian ones. You can buy all the Maestrini fittings from ASAP Supplies in the UK or SVB24 in Germany. They'll ship to you. They are expensive but worth it; bulletproof and last almost forever.

[GordMay]

Greetings and welcome aboard the CF, John.

What Dockhead said.

CW617N / CZ122 is classed as stamping brass and is mainly supplied as rod for forging stock although it is also free machining. The material consists mainly of 59% copper 39% zinc with a 2% lead addition that is finely dispersed throughout the microstructure. NOT SUITABLE!