Metallurgist advice on raw water inlet please

[mattonthesea]

Further to recent post, I have removed the raw water strainer as seen in the pictures. I was surprised by the amount of Verdigris. And then I noticed that the outlet tail was a domestic, brass tap connector with a 22mm copper pipe! Could this be the reason? Does it look like the metal on the thread has de-something or othered?

I then investigated removing the gate valve but found that the connection to the thru' hull fitting is completely glassed in with the fitting. My immediate thought was that this was very secure and that I could connect my new ball valve above the gate valve. However, I am concerned that the fitting may have lost some integrity in the probable 45 years that it has been there. On the outside it is a grating type and thickly covered in antifoul. I think that if I investigate this outside I am likely to break the grating.

I would be happy to drill a new hole and fit a new thru' hull fitting but I am not sure about filling the hole that is there. I have glassed before but only topsides; and with the hill of glass that is there around the inlet I am not sure how I would ensure that it is completely sealed. Furthermore, I would be working upside down from outside - something I have not done with glass before.

Does my anxiety show? I have looked at Youtube videos but are there any that are not by verbose Americans? Or is my first idea ok?

Recommendations please

Thanks in advance

 

[doug748]

Don't look great. I would investigate replacing it with a plastic Vetus type, perhaps in the engine department. Take care to mount it at the right height though and you would need to consider what you would do with a blockage in any flexible supply pipe.

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[DeepKeel]

Blue is bad. It indicates electrolysis has taken place. I would replace it. Glassing over an existing hole is easy if you have access to the inside, harder and messier if you don't.

 

[Bodach na mara]

Gate valves are horrible things and have no place in a boat, especially not in inlet pipes. The 22mm fitting looks like it has de-zincified. It was probably fitted only because it was the only one easily obtainable.

 

[Tranona]

Pointless putting a ball valve above a gate valve unless the gate valve is seized so it is just essentially a metal tube and not used as a valve. Best remove it anyway including the glassing in and replace it with a bronze or DZR through hull of the same diameter which I expect is 3/4" or 1". You should not need a new hole, just clean up the faces to get a good landing for the lock nut and flange. Then hose to the Vetus type filter.

The verdigris is nothing to worry about but the threads definitely show signs of dezincifiction. Brass tails are not uncommon and may or may not dezincify, so best avoided now that DZR ones are available (as are bronze).

 

[Graham376]

I would dig the lot out and fit a proper through hull, ball valve and Vetus strainer. On my screen that one looks to have a pink tinge to the threads, so did one of mine below which didn't take much effort to fracture -

 

[superheat6k]

Fir Forespar Marelon and then find something else to worry about.

 

[vyv_cox]

I think those strainer housings are usually bronze. File a clear area on the side and compare the colour with known brass, e.g. plumbing compression fitting. Advice on this on my website.

However the advantages of a Vetus strainer above the waterline are considerable, so well worth doing if possible.

 

[jaminb]

Fir Forespar Marelon and then find something else to worry about.

I have Forespar Marelon valves on my new (to me) boat, some are stiffer than others. Any maintenance / lubrication tips or suggestions ? Boat will be hauled out for a few weeks. Thanks

 

[penfold]

I have Forespar Marelon valves on my new (to me) boat, some are stiffer than others. Any maintenance / lubrication tips or suggestions ? Boat will be hauled out for a few weeks. Thanks

From forespar themselves, although I'm baffled by the warning against petroleum grease followed by recommending lithium, which is invariably a petroleum based grease.

 

[jaminb]

From forespar themselves, although I'm baffled by the warning against petroleum grease followed by recommending lithium, which is invariably a petroleum based grease.
View attachment 124505

thanks

 

[Graham376]

Surprised the Forespar need lubricating, our TruDesign have been fitted for 6 or 7 years now and still operate smoothly with one finger even after not being turned for several months when we're on board.

 

[mattonthesea]

UPDATE

thanks for all he input. I took out the old fittings completely. First time using an angle grinder and pleased that I only took one 2mm indent next to the hole! The glassing around the thru' hull fitting and over the gate valve connection actually came out very easily. A few taps with a hammer on a socket the size of the fitting and it came away. I suppose it's because it was a mechanical rather than chemical attachment. Anyway, cleaned up nicely and new Tru-design fitting and ball valve sikaflexed in place a la Tru-design video. Now I just wait for spring to put her back in the water Meanwhile I may put a holding tank in!

Thanks again