Eek! Quality Seacock fittings on a Jeanneau...

vyv_cox.... Thanks, I learned something today!! Unfortunately I have seen people recommend the Naval Brass.... I used all bronze fittings when I replaced the 17 thruhulls and seacocks on our trawler.... Great fun it was, as I did all the work!!

I don't know if any of you have ever seen this site...but this fellow is a professional mechanic/technician in the marine world and he has put together this site.... I followed his ideas and used many of the same items....and it worked out fantastically! It does go along with some of the suggestions the gentlemen here have made:
http://www.pbase.com/mainecruising/replacing_thruhulls
 
[QUOTE=ctva;4053626................ If I do need to replace the through hull strainer, which I assume is bedded in with Sikaflex, has anyone done this or got any advice on how best to do it?

I had to remove a thru hull last week (didn't mean to, but I broke the bedding seal when removing the 90deg elbow).

Looks like it will come out without any cutting to me.
back off the nut. reattach the ball valve and lock the nut against it at the top of the skin fitting.
With the wrench on the valve flats, turn the skin fitting clockwise (looking from inside) & it should back out for you (screwing it out will clean the threads at the same time!).
 
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Yes, I've seen that site before. Very thorough treatment of the subject and well photographed. You seem to have much greater choice of quality fittings over there. Is DZR (CZ132) used in USA? It was introduced here to combat dezincification in household plumbing in soft water areas, such as where I live where our drinking water is sourced in hills with peaty soil.

Again though, there are differences on this side of the Atlantic, where tapered threads are rarely used on seacock assemblies.
 
vyv_cox said:
...ctva's photo shows the material of the ball valve, MS58, which is a leaded brass...
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Is this good or bad when used with other types of bronze metals in the other fittings?

Is there a manufacturer / supplier that can guarantee the composition of the through hull fitting, ball valve and hose tail that I need for this set up?



john_morris_uk, you've read my mind as that was going to be done anyway but thanks for the details and the router bit too. I tend to be a 'Clyde Built' type of person!!
 
ctva said:
Is this good or bad when used with other types of bronze metals in the other fittings?

Is there a manufacturer / supplier that can guarantee the composition of the through hull fitting, ball valve and hose tail that I need for this set up?

john_morris_uk, you've read my mind as that was going to be done anyway but thanks for the details and the router bit too. I tend to be a 'Clyde Built' type of person!!
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You could try Mack Engineering http://www.mackengineering.co.uk/, near Glasgow airport if I remember correctly. I bought lots of bit from them and they ordered in anything not on the web-site. I did have trouble with 2 items but ASAP couldn't source them either and Mack were cheaper for same item, plus I was driving past them on way to the boat.

Good point about backing pad. Hull with liner is quite thick but Jeanneau cut back the area around the fitting and it is very thin at that point. I can't remember the measurement on my boat, suggest you measure it for interest when fitting removed (might get a shock).
 
ctva said:
Is this good or bad when used with other types of bronze metals in the other fittings?
Is there a manufacturer / supplier that can guarantee the composition of the through hull fitting, ball valve and hose tail that I need for this set up?
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Every decent producer everywhere but UK, sorry but UK with that "DZR brass" is Unique as usual. :p
I have bronze/copper plumbing at my house, from local shops here... hard to find now as costly, but available.
Just google "Bronze plumbing".
for instance: http://www.vetusmarine.com/Shared/PDFs/Page 205.pdf the alloy is actually listed, naturally this is a cheat :D ("bronze: CUPB5SN5ZN5...") - and this actually is not bronze! this is gunmetal... but at least it's said.
Bronze is CuSn 1-14, and not much more in.
UK producer http://catalog.buckalgonquin.com/vi...s/bronze-ball-type-seacocks?&bc=100|1426|1598
 
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vyv_cox said:
Yes, I've seen that site before. Very thorough treatment of the subject and well photographed. You seem to have much greater choice of quality fittings over there. Is DZR (CZ132) used in USA? It was introduced here to combat dezincification in household plumbing in soft water areas, such as where I live where our drinking water is sourced in hills with peaty soil.

Again though, there are differences on this side of the Atlantic, where tapered threads are rarely used on seacock assemblies.
Click to expand...

I think you can buy fittings for use with whats known as PEX tubing for plumbing....made of that material...but that is all I know of.

Ahhh, thats right...you use a "BST"...or British Straight Thread....which is unlike our NPT ..national pipe thread that is tapered.... So, I guess if you were to use the bronze fittings we have...you would have to buy the whole kit...from thruhull to hose barb from the same manufacturer/style.... I do know that they are not interchangeable...
 
ctva said:
Is there a manufacturer / supplier that can guarantee the composition of the through hull fitting, ball valve and hose tail that I need for this set up?
Click to expand...

I don't know about guarantee, but ASAP Supplies list the material for all their fittings, and are trusted by most people to get it right.

Pete
 
JAT said:
Ahhh, thats right...you use a "BST"...or British Straight Thread....which is unlike our NPT ..national pipe thread that is tapered....
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Almost :)

It's BSP, British Standard Pipe. This is parallel by default, but you can add a T (BSPT) to indicate that it's tapered. Both versions are used, but on boats our ball valves and skin fittings are invariably parallel. Hose barbs may be tapered.

We do see NPT over here, but usually only in small sizes on fuel fittings, probably to American designs.

Pete
 
prv said:
I don't know about guarantee, but ASAP Supplies list the material for all their fittings, and are trusted by most people to get it right.
Pete
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Yessss... they do. According to ASAP their "bronze valves" have brass balls inside - honestly stated, granted, can be trusted ;)

BTW: "inch" threads are in use all over the world, here also in plumbing, though everything else is metric. Not sure it's perfectly same threads, but my plumber thinks so, so I bought some bronze bits here and will try on boat :)
 
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Rossynant said:
Every decent producer everywhere but UK, sorry but UK with that "DZR brass" is Unique as usual.
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DZR did start as a British Standard to combat dezincification in soft waters in the UK but it is now an International standard material CZ132. It is pretty much as resistant as bronze but only slightly more expensive than brass. Blakes seacocks, often held to be one of the better ones, have been made from DZR for about 25 years. Mine are that old with no dezincification at all.
 
Troubadour said:
Can I give this a bump please, in case anyone has any idea about the black surface, may not have been seen as it was an edit.

I've added some more pics to https://picasaweb.google.com/113567095843010399028/Seacocks?authkey=Gv1sRgCMWboZff7-O6eA
Something that puzzles me is why some of my brass skin fittings and elbows are black. It's all the ones in the heads, not the engine intake or the galley drain.
Any ideas anyone please?
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I would give odds it is the metallic fittings reacting with H2S - itself generated by bacteria acting on the waste - or dead water in the plumbing system.
Sea water left for a while with closed seacocks can result in a whiff of H2S when you first pump out the heads after a while not in use, ditto if you have a seawater rinsing tap at the galley sink.

Graeme
 
pagoda said:
I would give odds it is the metallic fittings reacting with H2S - itself generated by bacteria acting on the waste - or dead water in the plumbing system.
Sea water left for a while with closed seacocks can result in a whiff of H2S when you first pump out the heads after a while not in use, ditto if you have a seawater rinsing tap at the galley sink.

Graeme
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Did you look at it before making this diagnosis? Perhaps you can explain why the elbow, skin fitting and its nut are completely coated, plus a few blobs on the hull, whereas the valves have smears over the parts that the paint brush touched.
 
vyv_cox said:
It's paint, or some bituminous coating, surely? The first photo, of the skin fitting and nut, has a blob of it on the GRP.
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I think the first photo has a black plastic nut with a broad flange (hull side) -and there is a fair bit of either sika or white mastic/ RTV smeared partly over it. Hence the "black marks?)
On the valve body, the corrosion appears to spread from the operating shaft (photo 5), and I think the acidic solution -pushed out he leaky seal (drips only over months?) has eaten the plating on the valve body slowly. You have a few PSI on the outside, so any H2S in seaward water side has time to go off , forming an acidic solution which very slowly eats the body. Copper elbows go black quite readily in the presence of a low concentration of H2S.
You can get this sort of minimal leak if you have growth on the seaward side of the ball valve, - operating the valve abbrades the seating material causing wear..

I would suggest power washing the seaward side (valve closed!!!) if you can while ashore? Helps remove organic material which can decay.

Graeme
 
I'd be very surprised if it was a plastic nut holding in a skin-fitting below the waterline. Fortunately, you can see the same black plastic in all the threads going into the valve. I'm betting that it is a brass nut and washer coated with something. Perhaps the OP can clarify.
 
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I've added some more photos - inc one of the engine seacock which is not black - from which you can see that all the nuts have flanges and they are not plastic.
https://picasaweb.google.com/113567095843010399028/Seacocks?authkey=Gv1sRgCMWboZff7-O6eA
The flanges are black where they are not covered with Sikaflex, it's not paint on the Sikaflex.
Most of the odd black stripes on the plated valves appear to be black marker pen where they are not just dirty gunge.
It is more like a chemical effect than a paint.
I think the H2S idea may be the answer, I had wondered about something like that before.
When I got the boat it had clearly been laid up afloat an awful lot evidenced by green decks and sails and the prop shaft crevice corrosion. So if it is H2S it's bacterial not human production!
It had been at Tollesbury mostly, don't know what the water is like there, and prior to that Levington up the Orwell so not very salt there I guess.
Thanks for the ideas!
 
Mistroma said:
... I just loosened the nut inside the hull and twisted the strainer with a Stillson wrench. Bloody big Stillson (~900mm) but smaller would be fine as long as jaws fitted over the lip at side of the strainer...
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Bit the bullet and removed it today. It was one of thoes jobs that you worry about prior and then when you do it, easy peasy! I only used a 600mm Stillson which worked a treat. Took all of 5mins! I've still to clean it up and check how far into the metal that the 'pink' goes.


Mistroma said:
...Good point about backing pad. Hull with liner is quite thick but Jeanneau cut back the area around the fitting and it is very thin at that point. I can't remember the measurement on my boat, suggest you measure it for interest when fitting removed (might get a shock).
Click to expand...
It was actually not bad. The pic in the 1st post looks like a big cut-away but in reality it is a 2mm dept at the outside only to provide a level base for the washer and nut. I'll still be putting in a backing pad as should have been put in in the first place.
 
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