Through hull.

[mestrezat]

One of my through hulls has decided to no longer shut off. It’s one of the old style that has tapered sides as the boat is 35 years old. I’ve undone the large bolt that keeps it tight against the big washer and pounded it with a hammer. No good. I sprayed PB Blaster around the edges and then used one of the chain clamps normally used for oil filters. Again, no luck. Even hit the wrench with a sledge to no effect. I’m wondering if I heat it with a propane torch if that’s would do any good? Any suggestions?

[Suijin]

Pictures would help.

If you can get it to turn that’s the first step. Inserting a wrench handle from the outside and turning it with another wrench sometimes works. Another tactic is cutting the flange like a pie with an angle grinder, breaking the flange off, then pounding it out (or in). A little heat can help if it’s bedded with 5200 but be careful.

[Pete7]

If this is a gate valve then just remove it and bin it, they have no place on a boat IMHO.

https://marinehowto.com/seacock-thru-hull-primer/

Its replacement, well been discussed alot on here so worth a read.

Pete

[mestrezat]

It’s not a gate valve but a valve thats made of bronze that fits in inside a sleeve that is tapered. Wider at the handle end and slightly narrower where it bolts into the thru hull. I’m trying to get it loose so I can turn it before cutting the thru hull out. Suggestions on getting it loose enough to turn?