SailNet Community banner
1 - 1 of 1 Posts

· Telstar 28
43,281 Posts
Reaction score
First of all, you shouldn't be using PLASTIC through-hulls below the water line. The only "plastic" through hulls that are safe to use below the water line are the Marelon ones, which are glass reinforced nylon.

You can use Marelon through-hulls with bronze seacocks... but most sea cocks are NPT threaded while the through-hulls are NPS threaded. If you're going to do this, use a bronze flanged adapter instead... this will have female NPS threads on the bottom for the through-hull and male NPT threads on the top for the seacock.

Personally, I think that you'd be better off using Marelon valves with Marelon through-hulls....but if you don't maintain the Marelon valves properly, you will break the handles off of them when they seize up. The Marelon valves need to be exercised regularly—at least once a month—and greased once a year.
1 - 1 of 1 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.