Thanks Rick. The cheap little valve in my home toilet will work for 30
years but on a boat "Y-valves don't work under pressure"....you really
can't make this stuff up!.

I'll look for a good valve. If that fails I guess I can just put in two
regular valves on a "T" - this would have the advantage of turning off
all water to the head (assuming I can remember which way to set them).

Carl

IMHO, the only marine Y valve worth buying is the Whale, but it still
might not work for what you want to do. For industrial valves, check
out http://www.mcmaster.com/