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On 13 Feb 2004 at 0:11, David V.N. wrote: > Are you sure?I'd hate to make a fatal,(to the engine anyhow). > mistake at this point.From what I've read,opinions on oil > weight are all over the place.The reason I went with the 20w50 > was because of the oil light being on STEADY after idling for > 20-25 minutes or so.Though this was occuring after playing with > timing,air bleed for idle and MPS tweaking and such.That also being > the cause for the SOS about oil cooling. One of the most common mistakes that we've ALL made is to use too thick an oil at some time. Thick oils will increase the pressure AT THE SENSOR, but they make little difference in the bearings, where it counts. Most of the pressure in the bearing is generated by the rotation of the journal, so the feed pressure is pretty irrelevant. OTOH, what the bearing really needs is plenty of oil, just to keep it filled. Heavier oil can help in an engine that leaks, because the thicker oil leaks out more slowly. Of course the engine also needs thicker oil in hot weather just to keep the final operating viscosity somewhat constant. One of the problems with thick oil in the winter can be that it can be hard to just get the engine to turn over when it is cold. You may have had a lot of break-in friction which made your engine run hot at first, so maybe this is over. OTOH, if your case was warped, it is fairly common to find the main bearing web warped outwards on abused old cases, so that the lion's share of the oil just leaks out there and spills back into the sump. One think you should always do when rebuilding a used case is to assemble the case empty and stick your hand in one of the cylinder holes with a thin feeler gauge. You should not be able to slip the gauge in the parting line next to the # 2 bearing. -- Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org