Repairing bronze, tapered cone seacocks

[skipmac]

My boat has all the original WC tapered cone bronze seacocks which are mostly in excellent condition with one exception.

The cones on some of them, mainly the two that receive the head discharge are pitted in spots. On the section of the cone that was exposed to the discharge when it was turned off was apparently left closed for long periods and the discharge caused some significant pitting of the bronze just in that spot. Otherwise the seacocks are solid but the ones with the pitting do tend to leak a few drops of liquid. Not a problem with sink drains and such but even a couple of drops of toilet discharge into the bilge is should I say, undesirable.

Would it be feasible to braze the pitted areas and fill with bronze, then smooth, polish and lap in the body of the seacock like normal maintenance? Would there be any issues with the bronze alloy used, potential for a galvanic reaction? Anyone know what alloy WC used to make their seacocks?

Thanks
Skip

[model 10]

That would be a tricky repair unless you were at a good machine shop. Welding up scattered pitting is best done with a metal spray and then re machine the taper. How about just remachine the taper? I bet you could chuck the cone up in a lathe and sand/file out some of the roughness and then lap the cone to the body.

[skipmac]

Originally Posted by Guy

That would be a tricky repair unless you were at a good machine shop. Welding up scattered pitting is best done with a metal spray and then re machine the taper. How about just remachine the taper? I bet you could chuck the cone up in a lathe and sand out some of the roughness and then lap the cone to the body.

Unfortunately some of the pits are too deep to lap out. Not at the boat but from memory some small spots down 1/4" more or less. In a very small area and not worried about sinking the boat.

[model 10]

If it is just a small area they could TIG weld some bronze scrap into the low spot and then you could file it smooth again.

[Cheechako]

I have found they are often pitted some. Some have casting voids etc in the surface also. None of these was a problem. I use lanolin in lieu of grease though. If it's not leaking don't worry about it. Clean it, coat with lanolin and install it.

[rpjn59]

How about removing them and shipping to manufacturor. I have a '66 Bristol and the supplier was still in business 4 yrs. Ago, dagnabit,I can not remember there name, I actually order parts from them and lapping compound. I'm guaranteed to remember at 2 am, Ill let you know. Lapping the seacocks while still in the boat was basically useless do to lack of space and ergonomics, it takes alot of rotations to lap out defects.

[Sailmonkey]

Originally Posted by rpjn59

How about removing them and shipping to manufacturor. I have a '66 Bristol and the supplier was still in business 4 yrs. Ago, dagnabit,I can not remember there name, I actually order parts from them and lapping compound. I'm guaranteed to remember at 2 am, Ill let you know. Lapping the seacocks while still in the boat was basically useless do to lack of space and ergonomics, it takes alot of rotations to lap out defects.

Must be spartan. WC is long gone.


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[skipmac]

Originally Posted by Sailmonkey

Must be spartan. WC is long gone.


Sent from my iPhone using Cruisers Sailing Forum

As far as I know, Spartan is the only company still making bronze, tapered plug seacocks, and seem to be quite proud of them based on what they cost.

[skipmac]

Originally Posted by Cheechako

I have found they are often pitted some. Some have casting voids etc in the surface also. None of these was a problem. I use lanolin in lieu of grease though. If it's not leaking don't worry about it. Clean it, coat with lanolin and install it.

Interesting, I use lanolin as well in mine. Problem is the seacock is leaking. It's only a very small leak but it's in the head discharge line and I'm not too happy about even a few drops of that in the bilge.

[Maine Sail]

Originally Posted by skipmac

Interesting, I use lanolin as well in mine. Problem is the seacock is leaking. It's only a very small leak but it's in the head discharge line and I'm not too happy about even a few drops of that in the bilge.

Clean cones really well then Cabosil/epoxy fill the voids and then re-lap.. The valves only go quarter turn and ride on grease this fix works and will lasts for quite some time. The Spartan grease works considerably better than any other product I have used including lanolin. It may even solve the drips without epoxy. Lap as best you can then try the Spartan Grease.

[skipmac]

Originally Posted by Maine Sail

Clean cones really well then Cabosil/epoxy fill the voids and then re-lap.. The valves only go quarter turn and ride on grease this fix works and will lasts for quite some time. The Spartan grease works considerably better than any other product I have used including lanolin. It may even solve the drips without epoxy. Lap as best you can then try the Spartan Grease.

Now why didn't I think of epoxy? Thanks.

What about MarineTex instead of Cabosil in West Epoxy (these are the two options I have on hand)?

And I'll get some of the Spartan grease as well.

[keepondancin]

I had the same problem. I used the lapping compound and grease from Spartan and solved the leaking I had. It didn't take an extreme amount of turns to lap them. If turned them enough time that the complete surface was impacted by the lapping compound. Much easier than I anticipated.

[Maine Sail]

Originally Posted by skipmac

Now why didn't I think of epoxy? Thanks.

What about MarineTex instead of Cabosil in West Epoxy (these are the two options I have on hand)?

And I'll get some of the Spartan grease as well.

Most epoxy products will work and MarineTex is just another epoxy.

[skipmac]

Originally Posted by Maine Sail

Most epoxy products will work and MarineTex is just another epoxy.

True but from experience not all epoxies are created equal and some work better in some applications that others.

[Cheechako]

Originally Posted by skipmac

Interesting, I use lanolin as well in mine. Problem is the seacock is leaking. It's only a very small leak but it's in the head discharge line and I'm not too happy about even a few drops of that in the bilge.

Yeah, you don't want that leak! All of mine have been W/C or Asian made. Real long tapers, probably 3-4" long, so a pit or two etc isn't a problem. How long is the mating surface on a Spartan?
Well I just Googled to see. Boy there are several threads about "dripping Spartan seacock" In the pics the plug looks very hollow... I wonder if they go out of round a lot? That could cause a problem. Are you able to measure the roundness with a caliper or micrometer?