The top ridge needs to be cut with a ridge cutter. Trying to hone it off
will just make a mess. This needs to be done so the new ring does not smack
against it as it will have a new sharp edge that may be just a little bit
wider than the worn one. Just as important as ring gap is the ring lands in
the pistons. At this mileage the lands are most likely worn and replacing
the rings doesn't help that much. As for honing, you need to real careful,
the cylinders are already worn and a few thousandths can disappear very
quickly. Than you get to listen to those strange piston slap noises that are
sometimes confused as knock. If you visibly break the glaze, you are
removing metal. If the cylinder is worn enough to warrant oversize rings,
you will also need oversized pistons. See why these are almost always sold
as sets? You have a used engine, and new rings does not change that.

For ring replacement, try to find a set that has a one piece oil ring. The
three piece rings use some oil.  I have also used the "gap less" rings by
total seal. Expensive but they do almost eliminate blow by.

Dennis

>From: "Giasson, Pascal (DNR/MRN)" <Pascal.Giasson@GNB.CA>
>Reply-To: "Giasson, Pascal (DNR/MRN)" <Pascal.Giasson@GNB.CA>
>To: vanagon@GERRY.VANAGON.COM
>Subject: Piston Ring Replacement
>Date: Sun, 13 May 2007 23:13:46 -0300
>
>I need a few opinions on this one.  I checked my piston rigns yesterday and
>the top rings were past their wear limits, even though the compression and
>leakdown test were pretty good.  The engine has 150 000 miles and seems to
>run strong.  The crankshaft endplay is just a little shy of .006" which is
>the wear limit.  I'm thinking of just putting in new rings.  I dont have
>the tools to check the cylinders and pistons but the cylinders have a very
>slight ridge at the top.  Am I asking for trouble by just replacing the
>rings?  Do I need to get the cylinder ridge honed out? Thanks.
>
>Pascal
>'84 Westy