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On 6 May 2006 at 2:48, Russ Wolfe wrote: > You are correct, they are to scrape oil into the exhaust valve guids. VW > started putting them on when they atarted having problems with exhaust > valve guide wear. I have no real proof of which way they are meant to work, but I can point out that in other engines quite elaborate valve stem seals are used to assure that oil is kept OUT of the valve guide. My impression was that oil in the guides, especially the exhaust guides, tended to get cooked and turned to coke in there. This made them get sticky or seize up. I thought the valve stem/valve guide problem that VW had was eventually solved thru metallurgy. I once had a shop advise me to replace my exhaust guides with cast iron guides and then leave the seals out to give them more lubrication. I let them do that, but it did not turn out to be good advise or a good solution. Since then, I've always stayed with the seals and the bronze guides and had no further problems. People with high lift cams and/or ratio rockers, will find that they don't have room for the seals. The extra valve lift needs all the room it can get. -- ******************************* Jim Adney, jadney@vwtype3.org Madison, Wisconsin, USA ******************************* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~