On Tue, 16 Apr 2013 12:28:39 +0100, David Billington
wrote:

On 16/04/13 01:58, Ed Huntress wrote:
On Mon, 15 Apr 2013 17:36:34 -0700 (PDT), BottleBob
wrote:

All:

Thought I'd mention these for those automotive techies that may not have heard of them.

Adios pushrods, camshafts, valve springs, rocker arms, poppet valves, etc. etc. Run more compression for more efficiency, higher RPM, cooler running engine, less maintenance. Too good to be true you say?? Check this vid out.

http://www.youtube.com/watch?v=pDsRa4eT7co

http://www.coatesengine.com/csrv-advantages.html

http://www.coatesengine.com/csrv-system.html

Ed's going to miss hot lashing the valves on a Saturday afternoon. JK LOL
Very nice! Axial-shaft rotary valves. They've been around for at least
60 or 70 years. g I think they were tried in aircraft engines even
earlier than that.

They always fail, mostly due to sealing problems. When I have more
time I'll see what I can find on the old attempts.

New materials may make them practical, but I wouldn't put my money on
it. If Mazda couldn't make their rotary-valve, pre-Wankel Cosmo last
in service, back in the '60s, I'm skeptical about this one.

But there's always hope....

Some rotary valve engines are over 100 years old now see
http://www.douglas-self.com/MUSEUM/P...aryValveIC.htm

Oh, that's interesting. That looks like the complete history of the
type.

It's funny that I haven't seen a reference to the Mazda engine for
over 40 years. It was a disk-type -- actually, the valves were
hemispheric -- and the valves were made of ceramic. It was quite
advanced, I thought, but it must have died without leaving any
progeny.

--
Ed Huntress