Thru-Hull Cap

[SV Miss Fe]

I discovered on my steel hull boat that a previous owner used a metal transducer which corroded. Luckily corrosion didn't affect the hull just the tube welded to the hull. I'd like to cut this tube off and put a marelon thruhull in place until next year when I have the time to add a new sonar unit. I know thru hulls use NPSM not NPT threads.

Does anybody know where I can buy a cap for the thruhull with the proper threads? Or am I stuck with a seacock?

[Cheechako]

Hmmm, not sure, but You could put a cheap ball valve or etc on for now.