"Steve" wrote in message
...

I just wish I had a good online reference to what a proper tapered plug
valve looks like..


OK, here is the best I could do with a quick Google. It is a commercial
TAPERED PLUG VALVE.
http://www.conind.com/pdf/plug%20valve.pdf

It's not a sea cock but it is a tapered plug valve and has straight threads
on the inlet side and standard pipe threads on the outlet side. In this
valve the plug could be removed and the plug lapped/overhauled without
removing the valve from the system.. With a plug in the through hull, it
could be serviced in the water. (I've done this many times) You could never
do this with a ball valve since the ball can not be easily removed and if it
is, there is no way to resurface the ball surface if scored.

Steve
s/v Good Intentions