Gary wrote:
Alec wrote:

If the copper pipe is fed directly to the brass valve they are
connected together. Use bronze or possibly plastic if you can find a
suitable sea water rated GRP fitting.

Alec

The valve is inside the boat and just controls whether the suction from
the bilge is on or not. It is only exposed to salt water on the inside
at one end (as the raw water crosses the tee) normally. I think I'd
like to try a marelon valve in it's place.

Comments?

I'd favor high quality bronze ball valve over marelon. The latter
requires periodic lubrication a couple of times a year. Forget to lube
and it can freeze causing the handle to snap off.

Good bronze valves seem to last forever. YMMV.

Good luck.

Chuck