Thruhull seacock driving me mad, need advice

[hd002e]

I uave a drain for the head sink above the waterline, the low quality pin valve gave up in the open position a while back and now that I have the boat out of the water its a good time to take it off and replace with a decent ball valve. The only issue is that I cannot for the life of me get the seacock off the thruhull. Both bronze, the fittings seem to have fused together. I can get a good grip on the retaining ring for the thruhull but then the seacock and thruhull rotate, dragging whats left of the sealant with it. If I grip onto the thruhull from the outside, the seacock does not budge no matter how much I hammer onto the pipe wrench grabbing the seacock from the inside. Short of grinding the thruhull flange from the outside, what options do I have? I am out of ideas at this point.

[more]

angel grinder and cut. 2-3 minute job or make THRU HULL PULLER

[hd002e]

Originally Posted by more

angel grinder and cut. 2-3 minute job or make THRU HULL PULLER

Yeah, maybe I need to do that. I would just hate wasting a solid bronze thruhull if I could get that d@mn seacock off it. I have plans to apply some heat tomorrow with a torch as a last resort.

[Bowdrie]

Originally Posted by hd002e

I have plans to apply some heat tomorrow with a torch as a last resort.

I'm not so sure I'd be taking a torch to a seacock/thru hull on a fiberglass boat.
You could very easily have a disaster on your hands.
Resin does not like torches.
As others have said, get out your oscillating tool and cut the thru hull off.

[Nekton73]

If you haven't already, take a look into the through hull from the outside and see if there are two little nubs inside, 180° from each other. If so, they are meant to give you purchase to counterhold the through hull as you turn the nut inside. A piece of flat bar and an adjustable wrench will serve. Of course, you need a second person on the outside to do the holding.