"Glenn Ashmore" wrote in message
news:6tRpb.999$62.845@lakeread04...
I am building a manifold to feed the washdown pump, air conditioning
cooling pump and watermaker bost pump. The supply is a 1 1/2" hose
coming from a 1 1/2" bronze seacock and Groco 970-1515 strainer. Engine
cooling water is supplied through a 1" hose that comes off a 2"x1.5"x1"
Groco manifold at the strainer

I would use bronze reducing tees except that nobody makes bronze pipe
nipple. Only steel, brass or stainless. All three of which are not
acceptable. So I have decided to fabricate it from a length of 1" wall
PVC tube with 1/2" threaded schedule 80 stubs for the valves.

Now comes the question of the valves themselves. I have some Conbraco
bronze ball valves that would work but my experience with them in the
past has not been all good. While the valve body is bronze the handle
is mild steel. On several deliveries of older boats the handles have
rusted to the point of being unusable and I have had to resort to Vice
Grips to operate the valve.

OTOH, I also have some Schedule 80 all PVC ball valves with stainless
handle retaining screws. I know that ABYC frowns on using PVC on
throughhulls but if the throughhull has a bronze seacock what are the
rules for down stream valves?

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?

--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
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