New Seacocks or Just Re-Bed?

[montenido]

Hi all,

I need to change out the plywood backing plates on several of my original bronze thru-hull/seacocks. They are the cone/drum type and operate okay, but show the 30+ years of use. As long as I am having the backing plates replaced, should I just go ahead and replace the seacocks also?
Chances are that the originals will last another bunch of years. I just don't want to throw away money that can be used elsewhere. What would you do?

Thanks, Bill

[JonathanSail]

If it were me I'd give them a thorough and close inspection before and after cleaning. Look for damaged threads, pitting in the valve/seats, cracks, reddening of Bronze due to zinc leaching, dents from impacts etc. If the seacocks look great after a thorough going over and servicing I'd probably reuse them. I'd probably be less likely to reuse the through-hulls especially since you'll be changing the backing plates and the exact thickness of the hull/backing plate may change etc. You may also choose to cut the old through-hulls out to ease removal of the seacocks.

You may want to improve the mounting setup over the stock arrangement. For instance I used fiberglass backing plates that were epoxied to the hull instead of plywood stuck to the hull with sealant. There are plenty of online resources that detail different installation arrangements including adding bolts that go through the seacock flanges, what type of backing plates and sealants to use and that discuss the topic of bonding (connecting electrically) the seacocks.

Some of the more obvious things that I would also do would be to replace all connected hoses and inspect/replace all hose clamps/pipe, etc.

Good luck with the upgrade,

Jonathan

[bobconnie]

Have them cked out and repaired if needed. Or repair, recondition them yourself if you feel able !they are simple and easily reconditioned. Or replace if not fixable. I would fix them myself but Im that way ! just my 2 cents

[malbert73]

Originally Posted by montenido

Hi all,

I need to change out the plywood backing plates on several of my original bronze thru-hull/seacocks. They are the cone/drum type and operate okay, but show the 30+ years of use. As long as I am having the backing plates replaced, should I just go ahead and replace the seacocks also?
Chances are that the originals will last another bunch of years. I just don't want to throw away money that can be used elsewhere. What would you do?

Thanks, Bill

i have some 45 year old cone type seacocks which work great, and require mild yearly maintenance. Just not sure I'd switch them, as new seacocks mostly have stainless balls for valves, which I am certain won't give you the same lifetime. The only issue is most of these likely have cones that will only fit and turn a certain way due to wear....

I also wonder if you can get the same quality bronze alloy these days.

[Stumble]

Malbert,

It is pretty easy to get the same bronze, it is just very expensive. In large part because the price of copper has gone up so much over the last few years. If you want to go the bronze route, look for siliconized bronze with no zinc in it.

Alternatively I am working on bringing titanium sea cocks to market (to match our titanium through hulls). Sadly I can't give you even a rough date, since the need was only recently identified. But the predicted cost should be close to siliconized bronze, weigh a fraction what it does, be more corrosion resistant, and be much stronger.

[Cheechako]

Clean and relube those great seacocks. Probably better than you can buy. Replace the through hull fittings.

[captain58sailin]

I once performed a refit on a 20 year old boat and all of the thru hulls were fractured at the base where the bell turned into the straight part with the threads. I would take a real close look at those for hair line fractures. You may want to dye test them. If they are not warped or red or cracked, put them back in with some 5200 and carry on the good fight.

[jla123sail]

I gave up on trying to keep the old bronze valves in working condition. Even after cleaning, graphite, lube and making sure the same valves were matched - they still would seize up- not even come out with the nuts removed. I didn't want a hose to go and leave me in a bad situation. Replaced all 7 with new bronze thru hulls and new ball valves. Just ground off the outside mushroom and pulled out. Peace of mind is worth the cost.

[Cheechako]

If you're willing to live a seacock that takes a little more effort to turn, Lanolin is the answer. It is unaffected by water, and you dont have to tighten the nut as hard as with grease to prevent drippage. The cone doesnt even have to be that perfect a surface.
"..were fractured at the base where the bell turned into the straight part with the threads.."
If you mean the thru hull fittings, (as opposed to seacocks) by all means replace them with new....

[captain58sailin]

Yes sir, I specified thru hulls at the beginning of my post.