Another Sparton seacock question

[Vincent]

I recently took my seacocks apart to regrease them. This is the galleyseacock. It was fun two years ago.The boat has been on the hard for almost 2 years now. It looks to me like a casting defect. The photo is more dramatic than handling together part. I am wondering if I should ignore it or replace the valve.

[JD-MDR]

I was advised to replace mine. I finally did replace them last month.

[Bill Goldsmith]

It depends. Are you daysailing the boat near your marina or mooring, or are you planning an offshore passage? If the former, and the seacock is not leaking, it might not be an emergency, but probably should be replaced before long, definitely not to be ignored. But if you are looking to add points to your "black box" (http://www.johnvigor.com/Black_Box_Theory.html) then I would replace now--but this means the entire seacock cone and barrel, not just the cone.

This looks more like either stray current corrosion or galvanic corrosion than a casting defect. The pinkish color on the cone might indicate "dezincification" of the bronze which weakens the metal because the zinc in the alloy is depleting. Are the other zincs (prop shaft/engine) installed and in good shape? Did the boat spend a lot of time in a marina with questionable electrical infrastructure? The marina (if applicable) can test for stray current.

[gonesail]

I recently took my seacocks apart to regrease them. This is the galleyseacock. It was fun two years ago.The boat has been on the hard for almost 2 years now. It looks to me like a casting defect. The photo is more dramatic than handling together part. I am wondering if I should ignore it or replace the valve.

there is a process where you lap the cone with lapping compound to smooth it out.
look here https://pbase.com/mainecruising/tapered_cone_seacocks.

[jbenagh]

Vincent, some of those pits look pretty deep and I agree about possible de zincification. You should probably start to plan on replacement. It looks
That said, these do look better than JD's which were wasp- waisted. That's not fixable but yours should end up with a decent sealing surface after lapping. As long as there's a decent amount of sealing surface, with grease, it should work ok. Read up on lapping, about what the abraded surface should look like. If you end up with that and no pinholes you are probably good for another season. You're right to be concerned but this might be salvageable.

[Vincent]

It was surprising to see this. The boat has been on the hard for almost two years now, but I don’t remember any deterioration the last time I greased them. And none of the other valves had this problem. I just took them apart, cleaned and re greased them all. I have the lapping compound, I will give that a try. If I launch this fall, it will only be for two months. I will replace this valve in December.

[JD-MDR]

Member “Cheliniger may still have some new ones for sale under cape dory hardware and rigging for sale. I bought mine from her