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<DIV><FONT face=Arial>Ken,</FONT></DIV>
<DIV><FONT face=Arial>Yes, lashing the valves is setting the clearance between
the rocker arm and the valve stem. Not sure what it's supposed to be on a 91. On
the bigger YS engines, it was about .004" and it's set with a feeler gauge. You
need to purchase some new bearings and come over to my house. I can show you
most of this stuff faster and easier than I can explain it. </FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Verne</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial></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> Wednesday, June 08, 2005 6:50
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: YS-91 almost done</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2>Verne,</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I've already got it back together and in the
plane. I used a small brush to clean the inside of the head, as best as
I could, and washed everything out with some old fuel that I keep for this
purpose. The compression seems good, but the problem I have is I never
had a new YS-91 so I don't know what it should feel like. I wiped a
little Klotz synthetic oil in the cylinder, before re-assembly, just to be on
the safe side.</FONT></DIV>
<DIV><FONT face=Arial size=2>I did scrape the entire valve and wiped
everything real good. </FONT></DIV>
<DIV><FONT face=Arial size=2>By lashing the valves, I'm assuming you mean to
check the back-lash in the rocker arm. What should that be? Is
there a tolerance for clearance or should it be "just snug"? I just
assembled the rocker assembly the same way I took it off.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Ken</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=verne@twmi.rr.com href="mailto:verne@twmi.rr.com">Verne Koester</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> Wednesday, June 08, 2005 6:19
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: YS-91 almost done</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial>Ken,</FONT></DIV>
<DIV><FONT face=Arial>You should be able to scrape the whole valve including
the mushroom area where the seal is made. Just scrape down the stem and
continue thru the radius and out to the edge. With a #11, you don't have to
worry about scraping too hard. You'll see the shiny metal of the valve once
the carbon is off. I use one of those "Gunk" brand carburetor dip tanks to
clean the head which includes the valve seats. About twenty minutes in the
tank, and you'll be able to brush the carbon off the brass seat with an old
toothbrush. For some reason, the dip tank doesn't even faze the carbon on
the valves. You can get the Gunk brand dip tank at Murray's. Once you've
done that, just wash the parts in water as hot as you can stand and blow
dry. I've never had the need to lap the valves with toothpaste or anything
else. Just reassemble everything and you should be good to go with lots of
compression. Don't forget to lash the valves. </FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Verne</FONT></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=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> Wednesday, June 08, 2005 5:28
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> YS-91 almost done</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2>Well folks, </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>This is what I did, I pulled the head and
took it apart just like Mike Darr told me to do. I didn't even lose
the spring retainers. </FONT></DIV>
<DIV><FONT face=Arial size=2>I chucked the stem up in my Dremel and
cranked it up on high, having some plumbers sandpaper handy I ran a strip
of 100 grit on the stem until it shines like new! That ought to do
it!! </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Not really, I did just like Verne told me too
and used a # 11 and scraped it gently just until the rough stuff was
gone. I wiped the stems with a rag and am ready to re-install the
valves. I am going to use toothpaste to re-seat the valves and my
question is, when I'm done with that can I just wipe the excess off or do
I need to clean it with something special before re-assembly.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks in advance,</FONT></DIV>
<DIV><FONT face=Arial
size=2>Ken</FONT></DIV></BLOCKQUOTE></BLOCKQUOTE></BLOCKQUOTE></BODY></HTML>