Thanks to all posters. As with all the simple questions, there is a range
of answers available. These newsgroups are great. Thanks again

"Keith" wrote in message
...
I personally don't think they are as good. I replaced three on my boat
with
Groco seacocks. You are correct about the plug valves working like the
valves on titration tubes. You would turn the rubber plug to the position
then tighten a screw on the other side which would smush the rubber plug
inside the housing, locking it in place. They had to be taken apart
annually
or so and cleaned and lubed. When you tighten them up, the rubber squeezes
up into the openings, especially in the closed position. You don't have
any
of these problems with ball valve seacocks, which are usually ss on Teflon
seats.

"Skip Gundlach" wrote in
message ink.net...
I'm a bit confused, apparently, by semantics or my limited exposure...

I hadn't heard of plug valves, so I went looking. What I saw looked
about
like every ball valve on the insides - except none had easily
position-noted
lever handles on the outsides.

A tapered plug valve led to visions of the kind of valves I used in
titration in school - a tapered seat with a matching taper on the
handle/valve, and, perhaps, a spring to hold it firmly down? - but that
was
not the deal. I presume from reading the various chatter on the topic
that
perhaps it (taper) refers to the threads at the bottom of the
valve/thru-hull?

In any event, I'm not the least bit sure how they're better than ball
valves, as that's what they look like. Those of you familiar with the
benefits of the type over a ball, what is their superiority?

Thanks.

L8R

Skip

--
"And then again, when you sit at the helm of your little ship on a clear
night, and gaze at the countless stars overhead, and realize that you
are
quite alone on a great, wide sea, it is apt to occur to you that in the
general scheme of things you are merely an insignificant speck on the
surface of the ocean; and are not nearly so important or as
self-sufficient
as you thought you were. Which is an exceedingly wholesome thought, and
one
that may effect a permanent change in your deportment that will be
greatly
appreciated by your friends."- James S. Pitkin