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<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></BODY></HTML>