dezincing of skin fitting

[johnnys]

Hi all, boat lifted on Friday and the dreaded pink skin fitting was obvious on one of five that are fitted below the water line in close proximity to each other. I am assured by the manufacturer that all fittings and valves are DZR but there is no hull anode, we have a sail drive with its own. Obviously I will change the affected ones but my question is: do you think an anode fitted nearby will help and if so is there a correct way of wiring it to five skin fittings i.e. in parallel.
Thanks in anticipation John

 

[VicS]

Change the affected one, if the pink colour is more than just the surface, for one you are certain is DZR

No wiring attached to it, or any others I hope.

If that one continues to show dezincification perhaps you should look for a reason. Goodness knows what it might be! What's it on.

If all else fails you could ceratinly fit an anode nearby and wire affected, or even all, hull fittings to it. Don't connect anything else though.

Marelon fittings would eliminate the problem.

 

[johnnys]

Thanks Vic, the boat is a Dufour 365 (2008) and the fitting is the heads outlet, there is certainly nothing connected to it.

 

[vyv_cox]

Thanks Vic, the boat is a Dufour 365 (2008) and the fitting is the heads outlet, there is certainly nothing connected to it.

I have recently been corresponding with another Dufour owner. Despite Dufour's assertion that all skin fittings are DZR I know for a fact that they are not. The boat I have been concerned with had chromium plated valves. I believe that these are never DZR and a check shows that they do not have the CR mark cast into them. Beware.

 

[VicS]

Thanks Vic, the boat is a Dufour 365 (2008) and the fitting is the heads outlet, there is certainly nothing connected to it.

If its a proper seacock replacing it with a Blakes one will ensure that it's DZR.

If we are talking just about a skin fitting with a ball valve or something screwed on it then you can replace it with a gunmetal one from ASAP.

Not been overdoing the acid cleaning of the toilet outlet pipes I suppose ?

But check how deep the dezincification is.

 

[Bandit]

Look on the valve if they are marked.

If you see fittings marked

CW 617 N they are Brass and not suitable for underwater use

CW 602 N is DZR and suitable for underwater use

 

[vyv_cox]

Look on the valve if they are marked.

If you see fittings marked

CW 617 N they are Brass and not suitable for underwater use

CW 602 N is DZR and suitable for underwater use

I have yet to see a materials standard marked on any skin fitting, valve or hose tail. This is one of the chief arguments of the YM seacock campaign - there is no way to tell what fittings are made from and there is widespread misunderstanding amongst chandlers, manufacturers and boatyards. The only exception is the CR mark on DZR valves but there is no equivalent for any other components.

 

[johnnys]

Thanks for the replies, not what I wanted to hear, sounds like I might end up replacing all. One other problem is that I can't find any 45 degree fittings other than 316ss, can I mix that with bronze or dzr brass?

 

[Bandit]

Vic S

I cant post photos, file probably too large?

I have emailed you one of a failed Valve from a 3 yr old Yacht.

 

[vyv_cox]

Thanks for the replies, not what I wanted to hear, sounds like I might end up replacing all. One other problem is that I can't find any 45 degree fittings other than 316ss, can I mix that with bronze or dzr brass?

No, stainless steel is unadvisable underwater and definitely not mixed with other alloys. Have you tried ASAP for 45 degree hosetails?

 

[Bandit]

Sorry Vic's and Vyv's mixed up too many VVVVs

I acatually sent this

Vic S

I cant post photos, file probably too large?

I have emailed you one of a failed Valve from a 3 yr old Yacht.

Vyv by email perhaps Vyv can post the photo ?

 

[Mrnotming]

Bronze who knows,

Because the ball valve on the loo outlet was jammed with lime deposits,it had to he removed.On the Dufour 36 with twin aft cabins, space to remove the valve was very poor, and my efforts caused the skin fitting to move in the hull.So I used the drastic measure and cut away the flange on the outside of the hull with an angle grinder.The fitting was substantial, only light surface pinking, and a pity to have to destroy it.Dismantled the lot and beat the plastic 1.1/2 half inch pipe with a mallet to loosen up lime and flushed repeatedly with Muriatic acid 20%.Many barked knuckles later and the assembly is back in place.Parts seemed of Italian manufacture and very robust.So well done Dufour in my case anyhow.Does not mean later production did not have parts fitted by another maker, so make sure that you do as earlier posters say,dismantle,inspect, replace and use the best bronze materials you can get for the job.Our boat is dry sailed a lot over a good many years now, so a boat left immersed every year will definitely need a good going over.I used to think Blake's pattern tapered bronze seacocks were a lot of bother and that these newfangled ball valves were the bees knees, but I have changed my mind and would fit the Blakes pattern in future.

 

[VicS]

Sorry Vic's and Vyv's mixed up too many VVVVs

That's what I guessed.

I recommend using Photobucket for posting pictures. That will reduce the size to one you select as you up load.
Tinypic.com, which is a Photobucket company, is a no frills version.

I guess you were trying to upload as an attachment.
If so you do have to reduce the size first.

A photoediting program will do it.

Microsoft Office Picture Manager will do it but it tends to replace the original if you are not careful... prob best to make a second copy and reduce that.

Simplest probably is Windows "Paint" ! Do a "Save as" or you'll loose the original.

 

[vyv_cox]

Vyv by email perhaps Vyv can post the photo ?

Here is the photo provided by Bandit. At his request I am not naming the boat manufacturer but I will say that they might be considered 'upmarket'. As he says, the specification is clearly marked. CW 617N is a leaded 60/40 brass, very similar to Tonval.

I have heard from a number of owners whose skin fittings, as this one, are made from a leaded brass unsuitable for underwater use. The statement made by the builder often goes 'We have been fitting these for XX years and have never had a complaint'. It seems this is not a strong argument. If you replaced your skin fittings after suspecting deterioration on a 5, 7 or 10 year old boat, would you consult the builder? I doubt very much whether I would.

 

[Talbot]

Change them all for Marelon, and stop worrying about them.

 

[KellysEye]

>Change them all for Marelon, and stop worrying about them.

Entirely agree, all ours are.