Paul Yaw wrote:

Paul wrote:

Bob Darrah wrote:

Help!!!

OK, young fellers, this old dog is trying to learn new tricks.  First
off, I've got this 20B spread all over my garage, I took it apart
because the rear rotor was completely full of carbon, the center rotor
was only half full, and the front was clean.  What I need is a proof of
concept engine that I might get 300 hours out of.

My chances of overheating this engine are very high.  For that reason, I
don't want to put any more money than necessary for new parts.  If it
works out, then I will see about a Pro built engine built with new
parts.

The end housings have very little wear and the rotor housings (all
three)  have a slight groove on one edge about .080" wide maybe .003"
deep, with some voids in the chrome in that area. I know that Paul Y
would probably not put this thing back together and he is right if I
were going for 2000 hours..

I neglected to mention that my own engines are built from the scrap
pile!  I am normally trying some kind of goofball port arrangement that
doesn't work, so the engines never get used for very long.

The seals are what I assume you call a three piece seal--a small
triangle, and an inner and an outer piece that go across the apex of the
rotor.  Just what are these one piece and two piece seals that you have
been talking about lately?

-Your rotor apex seals slots are probably 2 mm
-wide. This limits you to the two peice or three
-peice seals like you have I think.
-It is rather expensive to machine the rotors
-for 3 mm seals.

-The 3 mm one peice seals were used in very early engines
-and are used in racing engines. I don't think you
-can buy one peice 2 mm seals but I could be wrong.
-Did you mark what apex seal came out of where?
-If so you could probably re-use them.

Just for the sake of rotary trivia, the early carbon seals were 6 mm.
They look like two by fours in comparison.

-You could also probably  mix and match if you did not
-mind a little hard starting, a worse BSFC and
-a little less low end power. PL

Just make sure that all three pieces stay together.  If you mix apex
pieces it might not even start.

You can assemble a pile of garbage and in most cases it will run OK
under power.  The biggest problem is getting a good seal where the worn
and corroded side and rotor housings meet.  If you are just
experimenting, use lots of Hylomar and you will probably be OK for a
while.

PY

 
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