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<DIV><FONT face=Arial>Keith,</FONT></DIV>
<DIV><FONT face=Arial>I've had experience with two different sealed bearings for
the OS 1.4 by different manufacturers. I don't remember the manufacturer of the
first set (I actually went thru 2 of them in as many days). I do remember that
the seal was black. On one of those sets, I removed the seals and it made no
difference. </FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>The next set from the other manufacturer had red
seals similar to the primer-red color of high temp silicone. The manufacturer is
NTN and these are the bearings OS sells as replacements for the EFI version of
the 1.4. Left the seals in and never looked back. They're still in there with at
least 30 gallons of fuel thru the engine. Out of curiosity, I researched the
bearing and noted that it featured a high-temp lubricant manufactured by Shell
Oil. I don't know if this relates in any way to your situation but I'm throwing
it out here in case it does.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Verne</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV> </DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=tkeithb@comcast.net href="mailto:tkeithb@comcast.net">Keith Black</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, June 10, 2005 12:26
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Webra SS sealed bearing
update</DIV>
<DIV><BR></DIV>
<DIV>
<DIV><FONT face=Arial size=2>A while back I put the new SS sealed bearings
from Boca into my Webra 1.45. These bearings feel VERY smooth and it ran quite
well for about 16 hours of service. This is five to seven hours longer than
the standard bearings had been lasting me.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>At the Temple contest on the Friday practice day
the Webra started sagging at the top of uplines. I messed with the needles,
pump pressure, changed the glow plug and even added a head shim all to no
avail. Initially I didn't want to admit it, but my prior experience has shown
that reduced performance that can't be fixed with needle adjustments or
replacing the glow plug normally means the bearings are going bad. Therefore,
I reluctantly did a bearing change even though the bearings still felt REALLY
good. I assumed that at high speed they may be rough but I couldn't detect it
just from feeling them. In order to proceed with the contest I put my backup
Webra, also with the SS bearings, in the Aries and it flew like a
champ.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>After the bearing change I put the first Webra
into my new Impact and continued to have run problems. I rebuilt the pump and
that didn't help. In desperation I opened up more cooling on the Impact (cheek
cowls, etc.) in case it was an over-heating problem. I replaced the connecting
rod that seemed a bit loose (but I don't think that was the problem), and I
started using a foam clunk because I thought it might be getting gulps of
air due to the tank setup in the Impact. However, before test flying it I
spoke to Art Wagner who had just returned from Jetero. He had problems with
his OS 1.60 and had changed the bearings with new rubber sealed bearings but
it didn't help. He opened the 1.60 and found that the rubber seals were
dragging. His guess was the excess heat caused the rubber seals to swell (or
maybe just bad luck). He pulled the seals and, presto, the 1.60 started
running awesome again.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>After hearing this I pulled my Webra apart and
removed the rubber seals reusing the SS bearing with just a few flights on it.
I know the best way to trouble-shoot things are to do one thing at a time so
you know what fixes the problem, but considering that the last dead stick
ALMOST was curtains for my Impact I just wanted it FIXED!!!</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Today I went out and flew it and it ran like a
champ again. What fixed it? I don't know for sure, but I do think it's
*possible* that the rubber seals can in some cases drag and cause problems,
especially in the hotter weather like we're having now. I didn't see any run
problems until the hotter weather hit. This certainly could be a coincidence,
I don't know.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>A side note on the Webra I put into the Aries at
Temple. It did indeed run very well, however after each flight if I turned the
prop back and forth I would hear a squeaky rubbing sound. I had several others
listen to this too and we couldn't figure out what it was. At first we thought
it must be dragging on my nose ring or something, but I could never find
ANYTHING that it was rubbing outside the engine. This only occurred when the
engine was hot. So, was this also the sound of the rubber seals dragging due
to swelling from the heat? I don't know, but it sounds possible. If so it
didn't stop it from running well.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Obviously I'm concerned that removing the seals
will reduce the bearing life, but it also "possibly" fixed my sagging problem,
it definitely fixed Art's problem. </FONT><FONT face=Arial size=2>I'll have to
wait and see what type of life I get out of the ones without
seals.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I'm also tempted to remove the seals from the
engine in the Aries to see if the squeaking goes away, but I was told long
ago, "If it ain't broke, don't fix it".</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Keith Black</FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I don't think in all cases the rubber seals cause
a problem, but I think there's the possibility for them to cause a
problem.</FONT></DIV></DIV></BLOCKQUOTE></BODY></HTML>