Marelon Plastic Seacocks

CJU said:
The 1” Trudesign seacock kit is £48.01 from LeaSan here https://www.leesan.com/shop/seacock-kits/seacock-kits/tru-design-straight-seacock-kits.aspx A little bit more but worth it for a non corroding fitting.
My friends metal seacock snapped off after 8 years and some else’s after 9 years but I’m not sure what metal they were made of.
Apparently even DZR seacocks only have to be good for 5 years, according to the ISO std
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I have no experience of plastic seacocks as I use DZR ones from ASAP. After 10 years I replaced one just so I could test it. I hit it with a big hammer and cut it in half to check for any deterioration. No problem, so I did not replace all the others. After 15 years one of the originals started to suffer from wear/backlash inside between the shaft and the ball resulting in it not quite fully closing so replaced all the 15 year old ones while I was at it for peace of mind. What this may show is that by using good corrosion resistant materials may just mean the moving parts wear out before they corrode.

Www.solocoastalsailing.co.uk
 
KompetentKrew said:
Hello again,

Also, if anyone knows the cheapest place in Gosport to lift a 40' boat, that would be much appreciated, too.
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Not a lift but, provided your boat will sit on her keel happily, you can dry out at Hardway Sailing Club, leaning against the piles, for about a tenner. If you draw a lot, check the depth and make sure you can get off on the next tide - I know of someone who didn't and was stuck for a couple of weeks!
 
For me it is reassuring to know that my seacocks will work after months of inactivity. Knowing that they are not corroding is great. We have the majority of ours in Marelon. Three others are bronze through hulls and 316 s/s valves. I fell less confident with these.
 
The obvious place for a lift in Gosport is Gosport Boatyard. Depending on how long you want to be ashore, they do a weekend package.
 
Pasarell said:
If the surveyor said "plastic" I hope he was talking about above water! Truedesign and Marelon are, I believe, the only non metal ones approved for use below water by the likes of Lloyds and ABYC. There are many plastic skin fittings available that are only suitable for use above water. I don't think either of those have flush fitting variants but happy to be proved wrong. Truedesign and Marelon are both composite materials and would never be described as plastic
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I describe my increasing set of Forespar Marelon as 'Plastic', as do Aquafax and Force 4 !
 
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ctva said:
Ok, but not “very expensive” and four joints as opposed to two and multiple time the life span of dzr and no electrolysis and far better mechanically. Considering the importance of below water skin fittings and the cost of the boat, it’s a no brainer. At least to my simple brain anyway.
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I didn't say they weren't a better option, just much more expensive (i.e. twice the price). It wasn't me that decided to rubbish someones statement without even bothering to check the price first. I'm not sure where this extra joint has come from either. Its either 2vs3 or 3vs4 depending on if you count the hose onto the barb or not. There's no reason why either of them should fail.

I just recently replaced all my original seacocks on my 1985 built boat, visually they were all in perfect condition and still worked perfectly well, I doubt whoever bought the boat back 35 years ago is kicking himself for not specifying plastic, I doubt if they even needed replacing.

If I was fitting an entirely new through hull I would probably use plastic. But its certainly not unsafe or bad practice to use a material like DZR Bronze.
 
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superheat6k said:
I describe my increasing set of Forespar Marelon as 'Plastic', as do Aquafax and Force 4 !
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Whilst this thread is still going, is there much to choose between brands of Marelon seacocks?

Why did you choose Forespar over Tru Design, please? Just happenstance or for some specific preference?
 
Tru design are the best composite seacocks available. Standard fitment on some manufactured boats now.
 
Further to my post 6, I now remember that Forespar are the ones to think carefully about, a poster said:

"Failed Marelon seacock

I changed my broken Marelon seacock for a new one. Replaced my raw water intake seacock with your bog standard bronze one, and also replaced an old one that served no function in preparation for a sea tap.

I’ve now done a U-turn on my opinion on plastic seacocks. Given the choice I would not go for plastic seacocks again. I’ll explain why. Marelon seacocks are more expensive because they don’t corrode, however my seacock lasted less than two years and broke without any warning. Replacing a Marelon seacock with a like for like replacement is not so easy."

See:

http://todayiboughtaboat.com/2016/04/30/a-month-of-boat-jobs-in-ipswich/
 
VicS said:
In what ways are they better that Forespar Marelon ones. ? Better design or better material than Marelon ?
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Both, the actual ball valve they use has been in use on industrial marine aquarium installations for years with no issues. The thru hull design is better too, especially if you use the stress collar too. If you search failed marelon you'll find quite a few results. They had issues with handles snapping off. They look a bit flimsy too be honest. The trudesign valve is a substantial piece. Bulkier than the metal alternatives.
 
Pasarell said:
If the surveyor said "plastic" I hope he was talking about above water! Truedesign and Marelon are, I believe, the only non metal ones approved for use below water by the likes of Lloyds and ABYC. There are many plastic skin fittings available that are only suitable for use above water. I don't think either of those have flush fitting variants but happy to be proved wrong. Truedesign and Marelon are both composite materials and would never be described as plastic
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Tru design do recessed fiittings but your hull thickness would have to be good to accommodate them.

https://www.trudesign.nz/marine/products/37-skin-fittings-recessed
 
If you Google search under Marelon seacock failure (or similar terms) you will get plenty of hits. Do the same substituting Tru Design for Marelon and it is a different story. I've fitted two now and will always use Tru Design if I have the space.
 
Stemar said:
Not a lift but, provided your boat will sit on her keel happily, you can dry out at Hardway Sailing Club, leaning against the piles, for about a tenner. If you draw a lot, check the depth and make sure you can get off on the next tide - I know of someone who didn't and was stuck for a couple of weeks!
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Dumb question, but how would I be sure my boat will sit on her keel happily?

Reading in here and seeing people talking about drying out against a wall, I assumed it was just something all keelboats could do.

From the way she is stood on a stand in this photo suggests she is basically stable on her keel, right? I would assume that the weight is on the keel and not on the stand, which is only for balance.

JtxWk0b.jpg
 
Yes she would dry out on a wall no problem.

A mast rope and (tight) lines fore and aft would be prudent to make sure she didn't tip one way or the other.
 
KompetentKrew said:
Whilst this thread is still going, is there much to choose between brands of Marelon seacocks?

Why did you choose Forespar over Tru Design, please? Just happenstance or for some specific preference?
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Because I assumed "Forespar Marelon" was one term. Never heard of Tru Design ! Aquafax offer Forespar, which must mean something.

Better marketing on behalf of Forespar I guess. Anyway quite happy thus far, especially as I picked up a 1 1/2" new one from Netley boat jumble for just £50 !
 
CJU said:
LeeSan do a Trudesign kit, which includes skin fitting, seacock and tail, for various sizes at a price about the same as DZR.
Their website has all the spec sheets with dimensions if you are concerned about the size.

I have just changed mine and am very pleased with LeeSan and the fittings. A much better option than most modern metal ones in my opinion. Apparently even Blake’s seacocks are made with DZR have a limited life.
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This was what I used. I posted eArlier in the year about it
 
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