frozen ball seacock

[Captain Abo]

My a/c water intake seacock just froze. The handle moves but the ball inside apparently wont. It was working fine last weekend as we close this seacock to sail. We closed it last Sunday, and when reopened on Tuesday the a/c kept on giving error messages and no water flow. When I checked no water flow at all. Even removed the hose and nothing. Went on the water and tried a screwdriver from below while someone was moving the handle from inside and nothing. It is a Groco type ball seacock. Any Ideas?
Thanks
Abo

[tkeithlu]

I gather that the handle turns but the ball does not, right? One possibility is that while the ball is stiff, the handle has eaten it's way through the squared section of the bronze shaft to the ball. That's a steel/bronze connection with a rather sharp piece of steel, the handle. Try removing the handle and grabbing the shaft with a locking pliers, and then gently trying to turn it. Please don't shear it, because you still have the option of penetrating oil from above. Remove the hose, fill the neck with penetrant, wait, and try again. Whether you could resort to heat would depend on the setup - It would take a bunch of heat, not just a propane torch, given the way bronze conducts heat. It's not worth risking setting fire to your boat. Good luck with it.

On second thought, heat is not a good idea. I think the ball valve has plastic seals that would be destroyed.