Seacock/Through-Hull Replacement

[Dockhead]

Originally Posted by poiu

Correction to my earlier post, sloppy writing: Isn't used in valves 100% and is rarely used in through-hulls.

Even Blakes are DZR and I can't find any 100% bronze valves - body and ball anywhere in the UK. I'll probably have to go the the US and there many makers use brass balls in their valves.

Here are the Aqua Fax through-hulls (skin fittings):

Section 2I Page 5.pdf


They are made of LG2 Gunmetal -- great stuff! This is what I have on my boat.

[Dockhead]

And here's a good discussion of materials from the great Vyv Cox:

Brass and Bronze

[Rustic Charm]

Hi everyone, is anyone aware of a discussion about plastic seacocks at all. My boat is steel and I'd really like to eliminate as much as possible the clash of metals problem.

[nigel1]

I'm sure there has been a number of discussions on these.
Use the search function at top of page, select Google Custom Search.
Search for
Marelon
Forespar
Tru Design

Hopefully some thing will come up

[Dockhead]

Originally Posted by tedsherrin

Hi everyone, is anyone aware of a discussion about plastic seacocks at all. My boat is steel and I'd really like to eliminate as much as possible the clash of metals problem.

Lots of discussion in the archives.

Marelon sea cocks (made by Forespar) are impervious to corrosion, but being nylon, they absorb water and swell, and become hard to operate if not exercised often. So there are some downsides. You can read all about it in the archives.

[Maine Sail]

Originally Posted by Dockhead

Here are the Aqua Fax through-hulls (skin fittings):

Attachment 76039


They are made of LG2 Gunmetal -- great stuff! This is what I have on my boat.

Those are 85-5-5-5 bronze which is 85% Cu, 5% Sn, 5% Zn, 5% Pb... This is what any "good" seacock or skin fitting SHOULD be made of.

They can call it what ever they want, Gun metal, bubble gum bronze, tootsie pop bronze, but the composition is all that really matters. Bronze seacocks should ideally be an 85-5-5-5 bronze.

[Rustic Charm]

Originally Posted by Dockhead

Lots of discussion in the archives.

Marelon sea cocks (made by Forespar) are impervious to corrosion, but being nylon, they absorb water and swell, and become hard to operate if not exercised often. So there are some downsides. You can read all about it in the archives.

What do you mean with 'archives'? If you mean with just doing the search no dedicated conversations come up.

[Rustic Charm]

Belay that I've just worked out hiw to refine the search

[GordMay]

Originally Posted by Maine Sail

Those are 85-5-5-5 bronze which is 85% Cu, 5% Sn, 5% Zn, 5% Pb... This is what any "good" seacock or skin fitting SHOULD be made of.

They can call it what ever they want, Gun metal, bubble gum bronze, tootsie pop bronze, but the composition is all that really matters. Bronze seacocks should ideally be an 85-5-5-5 bronze.

85-5-5-5 is the common trade name (also known as Composition Bronze, Ounce Metal, or Hydraulic Bronze); but it may be identified as “Copper Alloy UNS No. C83600" (ASTM B62).

[Maine Sail]

Originally Posted by GordMay

85-5-5-5 is the common trade name (also known as Composition Bronze, Ounce Metal, or Hydraulic Bronze); but it may be identified as “Copper Alloy UNS No. C83600" (ASTM B62).

It has many names and in the marine industry it is often simply referred to as eighty-five three-five.. My only point was it does not matter what it is called, just that the composition good quality long lasting seacocks is 85-5-5-5....

I have a box of 85-5-5-5 seacocks that came out of a 1930's wood boat that was completely refit in 2004/2005. While very green with verdegris they clean up and work as new and have zero signs of corrosion in nearly 70 years of use... I have piles of old Wilcox and Spartan Seacocks I service at 40 +/- years of service. These too were made with 85-5-5-5 bronze..

[Cheechako]

It's often easier to search Google than to try to find old discussions here. Try putting Seacock and Cruiser's Forum together. Does your steel boat have standpipes at the sea valve locations? That would be a nice way to go... then you just need a valve rather than a seacock at the top above the waterline....

[exMaggieDrum]

I'm not an expert on seacocks but I do know that the hose clamps and hoses are a definite possible point of failure. May be not when you are off the boat and close all the seacocks (wow!) but underway in a seaway - when everything that can break will.

There are two types of "stainless" hose clamps. The cheap ones (which are the ones you usually see) are stainless bands of OK quality, but the screws are not good and will corrode. Unfortunately they will corrode underneath where the screw covers them and then fail without you seeing it.

The good all stainless ones are not cheap, but certainly cheaper than titanium. You can tell if a clamp is only part stainless with a magnet. Stainless is not affected by a magnet.

May be I just haven't asked enough or seen enough, but I have never seen or heard of putting titanium seacocks or hose clamps on a boat. Bloody expensive if you can find it. Good bronze can last a longggggg time if maintained well. P.S. the rule is all bonded or none bonded. So if you find that the previous owner (or you) did some but not all, then either do them all (difficult to do well and last) or removed the bonding from all underwater metals. Use zincs for the prop and prop shaft. BTW - props can turn pink too.

[Rustic Charm]

Originally Posted by Cheechako

It's often easier to search Google than to try to find old discussions here. Try putting Seacock and Cruiser's Forum together. Does your steel boat have standpipes at the sea valve locations? That would be a nice way to go... then you just need a valve rather than a seacock at the top above the waterline....

Yes, mine have welded in standpipes. I thoughts 'seacock' referred to the valve on a boat. Does it refer to the through fitting as well?

[Dockhead]

Originally Posted by Cheechako

It's often easier to search Google than to try to find old discussions here. Try putting Seacock and Cruiser's Forum together.

The Search facility on CF works very well -- try an Advanced Search while you're at it. You can also specify that search results will come up either by thread or by post -- very useful.

Google also works -- if you do an advanced search in Google, you can restrict the search to domain www.cruisersforum.com.

Good luck.

[Cheechako]

Originally Posted by tedsherrin

Yes, mine have welded in standpipes. I thoughts 'seacock' referred to the valve on a boat. Does it refer to the through fitting as well?

I'm no expert, but to me a seacock is flanged and fits directly to the hull (or a backing plate), anything screwed onto a threaded pipe or thru hull fitting is a valve to me.
If you have standpipes that terminate above the waterline, then maybe a plastic valve is worth a shot, or I wonder if you could get a plastic reducer or coupling and use a bronze or SS ball valve? the plastic fitting would isolate the valve from the steel.