Replacing throug hulls / seacocks

Minerva

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My insurer has been insistent that I replace seacocks & skin fittings this winter. Just had a look on marine superstore and I can get the following

1) Truedesign - ~£550
2) groco bronze ~£820
3) Blake’s £1,700.

Just as well I was sitting down. All costs above are excluding pipe / jubilee clips etc.

Instinctively I tend towards the bronze as plastic under the water line feels, a bit risky somehow. But is there any reason not to go truedesign? Seems to be considerably cheaper claim a 30year working life - although I presume the insurer will want them changed out before that.
 
Plenty plenty of boats have reinforced plastic through hulls with no significant problems. Keep in mind TruDesign/Randex are quite bulkier than metal ones, in my boat for example I could use them only in 2-3 through-hulls/valves out of the seven I have, in general I do not have sufficient space to fit them, can't freely turn the handle, etc :( FWIW I have DZR through hulls, every other year I brush them with a metal brush and they are still golden colour, in 15 years I replaced one because the handle broke and it got stuck, maybe another option to consider.
 
I replaced my aft head 2" fitting when it was about 12 years old. It was on perfect condition and pipes had zero build up inside. Slightly surprised as Jeanneau probably use cheapest valves they can find.

Tru-Design has been perfect. Very easy to turn and no worries about the skin fitting. No need for a support collar as the valve is in a small enclosed space. However, it is very bulky. I had to assemble the elbow and valve first. Then turn the skin-fitting from outside to screw fully bonded interior section into place.

I'd prefer it to more expensive option if I had to replace the forward head. Not a problem for now as I already replaced that with DZR after only 4-5 years use.
 
If you go for Trudesign, will you have a lot of bolt holes to fill in - will the insurers want that done professionally

Having said that, I had new-fit Trudesign fitted professionally as all dependant on the sealant - didn't cost a lot in the grand plan and I can sleep soundly. Fitted the pipes and the toilet myself.

From the other thread, is your hull solid GRP - or sandwich, in which case professional fit might be prudent.
 
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Last year I fitted a Trudesign for the toilet outlet, very easy to operate but there was plenty of room. If you have limited room then perhaps a DZR might be better. Check the dimensions, view one in a chandlery and then make your decision. Personally I liked the Trudesign as no corrosion at all.
 
We replaced our through hulls and seacocks with Trudesign gear a few years ago and are happy with them. They need no maintenance and have been no problem, I’d use them again without hesitation if needed. Fitting was an easy DIY job, getting the old stainless through-hull fittings out was a bit harder but they succumbed to an angle grinder with a wet towel in the fitting to cool it.
 
My insurer has been insistent that I replace seacocks & skin fittings this winter. Just had a look on marine superstore and I can get the following

1) Truedesign - ~£550
2) groco bronze ~£820
3) Blake’s £1,700.

Just as well I was sitting down. All costs above are excluding pipe / jubilee clips etc.

Instinctively I tend towards the bronze as plastic under the water line feels, a bit risky somehow. But is there any reason not to go truedesign? Seems to be considerably cheaper claim a 30year working life - although I presume the insurer will want them changed out before that.
You don't need Groco bronze. The sensible choice for ball valves is is between DZR or composite. DZR tends to be a bit cheaper and will be a direct replacement for your original ball valves and through hulls. TruDesign uses the same threads and sizes as DZR but are physically larger bodied which can cause problems with space. If you have Blakes valves, probably only the heads there is no need to replace them as they last indefinitely. If you do replace them they are very different fittings from ball valves so not interchangeable. If this is your Moody you wil probably find the original ball valves are bronze and unlikely to have siffered from corrosion, but may be stiff to operate and can't be "serviced" unlike Blakes cone type so you might have trouble convincing your insurer they are OK, but Blakes can be serviced as good as new and I would resist being forced to change them. The 4 Blakes on my boat are originaal from 1979 and sound as the day they were insstalled.
 
Thanks all - that seems awfy like a consensus.

I don’t have Blake’s just now, but with their captive bolts I thought likely to be easier to fit solo than the straight through style though hull. But an extra grand in my pocket will encourage me to put up with some nuisance.

On the DZR topic, I see to remember stuff being labeled as such, but pinking frighteningly early with associated brittle risk? Am I mis remembering?

I presume plastic truedesign is not appropriate for engine intake in the engine bay?
 
Blakes are not an appropriate replacement for ball valves as they require a completely different hole and the spigot is at an angle that makes them awkward for hose attachment unless in a space that wa designed for them.

You won't have a problem getting DZR. You will find suppliers label them properly (and they are 2-3 times the price of plain brass!). Actually while plain brass can dezincify it is far more rare than you might think, but obviously not an excuse to fit them.
 
Thanks all - that seems awfy like a consensus.

I don’t have Blake’s just now, but with their captive bolts I thought likely to be easier to fit solo than the straight through style though hull. But an extra grand in my pocket will encourage me to put up with some nuisance.

On the DZR topic, I see to remember stuff being labeled as such, but pinking frighteningly early with associated brittle risk? Am I mis remembering?

I presume plastic truedesign is not appropriate for engine intake in the engine bay?
I buy all my dzr fittings from ASAP Supplies. My oldest dzr ball valve is 20 years old and still good. I have never had a problem with dzr fittings that are clearly marked as such.
 
On the DZR topic, I see to remember stuff being labeled as such, but pinking frighteningly early with associated brittle risk? Am I mis remembering?
People send me photographs of a wide range of metallurgical problems, probably top of the list being dezincification of seacocks. I also keep an eye out for case histories on other forums. I have yet to see dezincification of genuine DZR. Beware any photos you see in the magazines of chromium or nickel plated valves said to have suffered dezincification. DZR fittings are not plated.

My Blakes seacocks, dating from 1984, are DZR. They remain in excellent condition.
 
Can I ask the OP - What reason have the insurance company given for requiring the seacocks to be replaced? Is it based on some sort of inspection / survey or is it just a routine requirement based on age rather than condition?
 
Can I ask the OP - What reason have the insurance company given for requiring the seacocks to be replaced? Is it based on some sort of inspection / survey or is it just a routine requirement based on age rather than condition?
Pants asked how old they were, I said “not sure but all operational”. In response they declined to cover me in the case of failure last season and were insistent on having them replaced when next out of the water.
 
Why your insurer wants them changed
Seacock small.jpg
When I come out of the water, I give each of mine a good welt with a rubber mallet. I didn't bother with this one, the state of the ball valve was enough to know it needed changing ASAP. It broke when I tried to undo the nut
 
Pants asked how old they were, I said “not sure but all operational”. In response they declined to cover me in the case of failure last season and were insistent on having them replaced when next out of the water.
If that happened to me I would switch insurer
 
If that happened to me I would switch insurer
I’m not too het up over it. After all a single point of failure would quickly lead to catastrophic loss. If I replace them this winter and they want them replaced in 5 years again, it may be different.
 
I have 6 sea cocks below the waterline and replaced 5 of them with Trudesign kit last spring. The 6th was in an awkward spot and is also bronze, so I am ok with it. My boat is 54 years old and the original through-hulls were ok, but the ones that had been replaced over the years were a bit suspect. So far nothing but praise for the Trudesign kit. It’s easy to spec and buy, and easy to fit with the right sealant. Good guides online too. But as everyone has said, I needed to be a bit inventive with the orientation as they are very bulky.

(edited as I got the numbers wrong!)

Here's some of the wreckage I removed. I'd been feeling guilty about it for a couple of seasons.

IMG_7879.jpeg
 
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as plastic under the water line feels, a bit risky somehow. But is there any reason not to go truedesign? Seems to be considerably cheaper claim a 30year working life - although I presume the insurer will want them changed out before that.
Your boat is probably made of "plastic"...

Trudesign have certifications from enough bodies and the nod from enough people who know stuff to allow me not to worry about it.

FWIW, I laminated a 10mm thick board and cut the backing pads from that, bedded on thickened epoxy because even the best plywood can rot out and where do you get a small piece from...?

Also, be prepared to spend out a bit on the "jubilee" clips - they're not all made equal (eg width and quality of the band and whether the 'teeth' are pressed or cut through the band, these latter being commonly called "High Torque" and are better for reinforced hoses AIUI ). Whether it's overkill I can't say, but I only go for W5 grade, A4 stainless - Jubilee, Mikalor & JCS inter alia do them but you have to hunt around a bit to get them.
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