X-Mozilla-Keys:                                                                                 

From: Paul <rotaryeng@earthlink.net>

We think burning cleanly for apex seal oil is crucial to the life of the
rotary.
I think Mazda engines would last a lot longer if Mazda addressed this
issue
in their car engines. Perhaps they were worried that people would
balk at keeping a separate tank of apex seal lube oil. Maybe
at the time they under estimated the importance of clean burning apex
seal
oil. The rotors on most engines taken out of cars are coated with
junk and the apex seals are stuck in the slots.

Paul Lamar

Brian D. Cain wrote:

I can prove that alone, not to mention the side seal grooves are
caked with the stuff.  The rotor faces have carbon baked on them,
presumably from 4-stroke motor oil not burning completely.  I have
been running a 96:1'ish ratio of oil to fuel premix for about the last
2500 miles or so on this automotive platform.  It's still running great
(infact I've been racing it quite a bit, outputting in the mid 300bhp
range) and it's doing quite alright.  Perhaps after the next several
thousand miles I will disassemble it to see how clean the engine is.

The last engine I did a rebuild on (mine), several months ago, had
rotors that were literally black with baked on carbon.  I spent almost
6 complete hours soaking, scrubbing, and brushing these things to
shiny silvery'ish.  I had to use pics and what-not to get the residual
carbon out of the side and apex seal grooves.  The seals also were
stuck in there quite well and I'm surprised the engine still worked.

I couldn't even imagine what making uneven spots and having a
generally-unsmooth combustion chamber 'bathtub' face and side
face on the rotor would do for possibility increasing detonation-prone
behaviour from all of this unburnt crap.

B

 
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