OK Paul, another stupid question:

I  purchased one of Tracy's engine rebuild kits for my 20B.  It  came
with
"competition" Rotor Oil Control Ring Springs and  they are color  coded
as
follows:

Qty.  3 - Outer "Competition"- powder blue
Qty. 3 - Inner -  Blue

Qty. 3 - Outer "Competition"- Ivory (looks yellow to  me)
Qty. 3 - Inner - White


Is there any easy way  to tell where the various colored springs go?
I have tried to use  the info on both the Mazdatrix website
(_http://www.mazdatrix.com/b3.htm_ (http://www.mazdatrix.com/b3.htm)  )
and
Bruce's
video to sort it out, but I  still can't figure it  out. Tracy's not sure
either.

My understanding is that the 20B engine is basically a  13B with an
additional
rotor stacked on the front.   I  therefore assumed that if I initially
ignore the   "additional front rotor", that the remaining rear and middle
rotors  of the 20B would be exactly like the 13b rotor arrangement.  Is
this
a correct assumption?? I then tryed to use  the  instructions from the
mazdatrix website to arrange the oil   control
ring springs on those two rotors in the same manner  described  for the
13B.
When I did it in this  manner, I was left with one of each  color
springs
to  put on the 3rd rotor (the additional front rotor which is  unique  to
the
20B) and this seems odd to me.

The  mazdatrix website  states that the front 13B rotor (my center  rotor)
gets the White and  Ivory (competition)  springs.......thus two white
and  two ivory   springs.  That leaves one of each remaining since I got
3  of  each.

The mazdatrix website states that the rear 13B  rotor (also my rear
rotor)
gets the Blue and Powder  Blue (competition) springs.......thus  two
blue and  two  powder springs, and again one of each now  remains since I
got  3 of
each colored spring.

So now I have one  of  every colored spring left which would make the
spring

arrangement very different for the remaining rotor (ie. every groove  on
this
rotor would have a different color spring.).  It  doesn't seem right
that this would be the case and this is  why I'm  Asking for help.  Where
did I go   wrong?

Don


I have no idea. If it were me I  would leave them out of an aircraft
engine all together. Oil scraper  rings just  cause friction, heat
and wear. I am in the process  of building an engine without them
to test the idea.

Mazda had to do it as without them the engine acted like a radial
engine with oil accumulating in the lower chamber. On start up
huge  clouds of smoke would come out of the exhaust. No worse than
an AT6  engine however :)

I had a Cosmo I drove for years with melted  oil control O rings.
No big deal. When it was running there was no  hint of oil smoke
and it did not burn a lot of oil anyway. Of course  the scrapper
rings were still in there. I am having the engine  assembled
without the scraper rings just to see what will happen  on
the dyno. I feel they are not really needed.

Paul  Lamar



Paul,
an engine without oil  scraper rings will smoke like you won't believe.
makes
way more smoke than the navy smoke  layers.
It is easy to figure out the position of the oil ring  springs. Each is
installed so the drag on the seal causes the  spring to compress on it's
self. Installed backwards, they  stretch and lose tension, again causing
smoke and oil  consumption.
Larry

My Cosmo never smoked  when it was running but it still had the scraper
rings. Just  the O-rings were shot. You are the first person that told me
that and I trust your judgment because of your vast racing  experience.
Dave Lemon did not mention that but he was still  reluctant to try it
without scrapers as he is building the  engine. Did you try just one
scraper ring?

Have you ever heard of "competition" Rotor Oil Control Ring  Springs?
Are they lower pressure than  stock?

BTW We have built engines with TES oil O-rings and  that works fine.

Paul Lamar


Paul,
I have never tried racing springs, nor do I understand the  need for them.
maybe they have less tenstion to reduce  friction.
I have also never tried one seal, If you look at the way  the seals orient,
the outer seal is protecting the inner oil seal  from seeing any combusion
gasses that leak past the side and corner  seals, so running without it may
shorten the life of the inner seal.  To me it is not worth the risk as
these
have never caused  a failure causing the engine to shut down.
Larry

That  is true but they do suck some HP due to friction.
How much oil do  they burn in a race situation?
This engine I am building will never  be used other than
on the dyno. It is strictly for experimenting  with such things
as fuel injection and ignition systems. We will  probably tear
it down more than once.

Paul  Lamar



Paul,
for sure it would be an interesting  experiment...... I would contact
mazdatrix or racing beat to see what they  know about the racing springs.
Larry

-

Is there any other 20B Builder on this list who can chime in on the
position of the various color oil control ring springs?  I don't plan to
leave
the springs or the control rings out, so I just need to figure out  where to
put them.

Don

Keep reading Don. Mark S Texas 20B chimed in.
You need to take a weekend trip down to 20B headquarters
in Austin :)

Paul Lamar



I'm no rebuild expert but on my 20B I placed the white oil control ring
springs facing the front of the engine and the blue springs facing the rear
as per this video:
http://www.rebuildingrotaryengines.com/videos/oil_control_rings_installation

According to the attached 20B both front rotors are oriented the same.