Mailing List flyrotary@lancaironline.net Message #26897
From: Chuck Dunlap <crayd@cableone.net>
Subject: RE: [FlyRotary] Carbon Build up.
Date: Mon, 10 Oct 2005 07:00:19 -0700
To: 'Rotary motors in aircraft' <flyrotary@lancaironline.net>
Message
Dave, that first picture looks suspiciously like my rotor that I pulled a couple of years ago, it was running without oil cooling due to a plugged eccentric shaft oil jet. Mine was also missing the corner seal plugs upon disassembly, I am sure they were installed. If your E-shaft jet is plugged, it may account for the low oil temperatures.
 
Chuck Dunlap
N616RV 13B - 505 hours
-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of David Leonard
Sent: Sunday, October 09, 2005 10:47 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Carbon Build up.

The first picture is the front rotor with the stuck and broken side seal with a piece missing. Wouldn't fit in the last message.
 
So the big question now is why.  Note the picture of the rotor face.  There is LOTS of carbon build-up.  So much for 2-stroke oil burning very cleanly.  I am mixing less than 1:100 (about 5 oz per 6 gal gas can).  I have thought of the following possible causes:
 
1 My oil may be running a little cool.  It maxes out at 160 and is usually closer to 140-150.  This could keep the rotors too cool and prevent burning of the oil.  Add in the modification to the oil bypass and this may be it, but it seems unlikely to me.
 
2 Running rich.  Because it is so hard to get the engine tuned, I am probably running very rich (the only way to keep it running), especially at low RPM.
 
Some of both?  Poor quality 2-stroke?  I have noticed that the 2-stroke oil does accumulate in the crank case.  That of course indicates that it does not all burn, and what doe burns does not necessarily burn cleanly.  Maybe using crank-case oil would burn less, and there would be less needed and less residue. 
 
Anyone else seen this?  Any ideas?

--
Dave Leonard
Turbo Rotary RV-6 N4VY
http://members.aol.com/_ht_a/rotaryroster/index.html
http://members.aol.com/_ht_a/vp4skydoc/index.html




--
Dave Leonard
Turbo Rotary RV-6 N4VY
http://members.aol.com/_ht_a/rotaryroster/index.html
http://members.aol.com/_ht_a/vp4skydoc/index.html
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