I'd second Evan's condern. I was on a boat once which had a head
feeding off the same intake as the genset. In a short time, the
genset dried out the head valves and pump and made them useless.
Replacement of the valves and pump leather and a check valve helped,
but you still couldn't flush the head with the genset running.

Michael Porter



"Evan Gatehouse" wrote:

snip

I don't think ABYC cares too much of what is downstream of the seacock.
Figure it out this way, if one of your PVC valves fail, it won't sink the
boat because you can close the seacock easily. You could also use Marelon
if you're worried about the strength of the PVC valves.

The only thing that worries me about all this manifold is the engine pump
starving the R.O. or AC pump because it sucks harder. On commercial ships,
the seachest is big enough to deal with this issue, but if I'm reading you
correctly, a single 2" intake is supplying everything?

Michael Porter Naval Architect / Boatbuilder
mporter at mp-marine dot com
www.mp-marine.com