Through Hull Question

I'm replacing a porta potty with a real toilet. I've drilled a hole in my hull and installed a through hull bedded with 5200. I've received mixed signals on installing the seacock. Some say coat the through hull threads with 5200 and screw on the seacock, others say use Teflon tape. Looking for 3rd opinion.

 

Coat the threads with pipe joint compound. It comes in a tube or a tin.
Use the 5200 to bed the thru hull to the hull, or you can also use a polysulphide.

 

If your hull is anything other then wood, use polyurethane (3M 5200 or similar) to bed the thru hull flange to the hull. If the hull is wood, use polysulfide. Use pipe dope on the fitting threads. Teflon works, but dope is the tried and true method. Teflon is a lot neater, especially if you have to remove it.

 

Here's a third third opinion. http://www.highsidechem.com/leaklck.html The blue one.

 

If you put 5200 it will ooze into the threads. That is good because it will keep the backing nut from unscrewing. As PAR says, use polysulfide on a wooden hull.