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<DIV><FONT face=Arial size=2>I use this method as well.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Don't forget Eric Henderson's tip to do the
disassembly/assembly inside a gallon zip-lock plastic bag unless you enjoy
hunting for valve keepers.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>The carbon build up is a normal condition and
should be expected of YS engines that experience long service
intervals.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I prefer to adjust YS valves by feel. With the
valves all the closed, there should be a perceptible "wink" in the rocker to
valve contact. After reassembly it may be necessary to adjust this several
times in the first ten flights or so.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Expect the clearance to get smaller as the valve
finds its seat.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Tight valves cost horsepower, loose valves break
valve train parts and cost horsepower.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV>John Ferrell <BR><A
href="http://DixieNC.US">http://DixieNC.US</A><BR></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=PatternFlyer@sbcglobal.net
href="mailto:PatternFlyer@sbcglobal.net">Ihncheol Park</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> Thursday, June 02, 2005 10:52
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> RE: YS-91 AC problem</DIV>
<DIV><BR></DIV>
<DIV dir=ltr align=left><SPAN class=828524702-03062005><FONT face=Arial
color=#0000ff size=2>I took the valve out of the head and chuck it up on
dremel (not so hard). Then, turn it on a dishwashing sponge that has
blue scrubbing thing (green ones, the heavy duty is not recommended). I
do it with a little soap on the wet sponge. After finishing, I
remove the valve from the dremel and hold it with rubber sponge. Then
use the scrubbing sponge on the side where it was chucked up on Dremel.
Do it slow and watch the valve carefully to prevent
damage.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=828524702-03062005><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=828524702-03062005><FONT face=Arial
color=#0000ff size=2>Ihncheol Park</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=828524702-03062005><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> discussion-request@nsrca.org
[mailto:discussion-request@nsrca.org] <B>On Behalf Of </B>Robert
Harden<BR><B>Sent:</B> Thursday, June 02, 2005 9:33 PM<BR><B>To:</B>
discussion@nsrca.org<BR><B>Subject:</B> Re: YS-91 AC
problem<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV><FONT face=Arial size=2>I don't remember Bill saying, but you have to
remove the valve stem from the guide first. Then I used a small
piece of fine sandpaper twisted and ran it through the guide up and down until
the carbon was removed. Maybe there is a better way to do this - any one
have suggestions? Now then, so that this doesn't happen again, use a
fuel that has all synthetic oil (no caster oil in it). Hope this
helps.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Bob</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=phoran@vvm.com href="mailto:phoran@vvm.com">Paul Horan</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> Thursday, June 02, 2005 8:29
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: YS-91 AC problem</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2>Ken,</FONT></DIV>
<DIV><FONT face=Arial size=2> What did he tell you to do
the cure the carbon problem.</FONT></DIV>
<DIV><FONT face=Arial size=2>Thanks,</FONT></DIV>
<DIV><FONT face=Arial size=2>Paul</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=mrandmrst@comcast.net href="mailto:mrandmrst@comcast.net">Ken
Thompson</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> Thursday, June 02, 2005 7:22
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> YS-91 AC problem</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2>Thank you to all who gave me places to look
for my problem.</FONT></DIV>
<DIV><FONT face=Arial size=2>Somebody gave me the thought that maybe it
was carbon deposits on a valve, I'm sorry I don't remember who. I
dismissed this theory because the valves seemed to be operating
properly.</FONT></DIV>
<DIV><FONT face=Arial size=2>Early this morning Mike Darr stopped by to
check out my damaged Excelleron and took a look at my motor for me.
He manually worked the valves and all of a sudden the compression came
back. It looks like there was carbon on the valves after all.
He told me what to do and I should have it fixed as soon as I get back
from Norfolk, a little trip this weekend to go out for the day on the USS
Theodore Roosevelt.</FONT></DIV>
<DIV><FONT face=Arial size=2>Thank you all again and thanks to Mike for
showing me what to do.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Ken
Thompson</FONT></DIV></BLOCKQUOTE></BLOCKQUOTE></BLOCKQUOTE></BODY></HTML>