<HTML><FONT FACE=arial,helvetica><FONT SIZE=2 FAMILY="SANSSERIF" FACE="Arial" LANG="0">Chris,<BR>
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The Webra is very easy on the main bearing. It's considerably larger bearing than in other engines of similar displacement so that's one key reason why longevity is better. BUT if run lean or the fuel is left in the engine after many flying sessions rusting things, after run oil is never used, etc., the bearing will bite the dust. Your fuel is fine<BR>
<BR>
The early sign will be
<BR>
very slight gritty feel as you turn the spinner just prior to compression. If the feel is smooth, the bearing is probably okay. Another progressive sign is erratic engine runs but eliminate all other variables first (bad fuel, poor cooling in your set-up etc.) When you start to hear the bearing, it's way too far gone and it may be ready to chuck a ball retainer, which could destroy your piston and/or liner. The balls are sliding in the races and not rolling. The friction from this action is severe, overheating the bearing and the bearing seat.<BR>
<BR>
Cool Power is what I use and I haven't had any problems. But I run the engine dry almost always after a session and almost always follow that with some castor oil as after run. There are several good methods that guys are using and you only need to choose one and stay with it<BR>
<BR>
Check Ed Hartley's website under engines. He has collected a bunch of info from all of us on care and feeding of the various 2 stroke powerplants.<BR>
<BR>
Matt K<BR>
<BR>
<BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">Subj:<B>Another bearing question.... </B><BR>
Date:10/22/2003 3:33:15 PM Eastern Daylight Time<BR>
From:<A HREF="mailto:chris@ssd.fsi.com">chris@ssd.fsi.com</A><BR>
Reply-to:<A HREF="mailto:discussion@nsrca.org">discussion@nsrca.org</A><BR>
To:<A HREF="mailto:discussion@nsrca.org">discussion@nsrca.org</A><BR>
<I>Sent from the Internet </I><BR>
<BR>
<BR>
<BR>
Hi!<BR>
I hear of guys getting anywhere from 35 to 400 flights on bearings:<BR>
<BR>
What are the first signs of bearing problems. Since starting Intermediate<BR>
practice in July, I have just got into flying the same airplane/engine<BR>
regularly enough to wear on an engine and tell the difference in<BR>
performance. I have 97 flights on a Zen/Webra 145AAR combination. I use<BR>
Cool Power 15% and after run oil religiously. I have a tach which varies<BR>
so much with light emissions that I deem it as unreliable. So what do you<BR>
look for?<BR>
<BR>
<BR>
Thanks, Chris</BLOCKQUOTE><BR>
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