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On 16 Jan 2002, at 20:04, Hal Sullivan wrote: > That's the area I looked at, and again I didn't see a difference. The > flywheel is off (I swapped the engine into a MT car, then "borrowed" the > flywheel after swapping it out again), so there's nothing in the > way. Curiouser and curiouser. Maybe when I get it up on the stand in a > few months for a teardown/rebuild I'll find it. I should mention that there is 1 more difference between an AT engine and an MT engine. Anyone who has ever torn down one of these engines knows that there is a little steel "cap" which plugs the hole in the end of the cam bearing tunnel. On MT engines this cap is installed with the closed end facing out, but the AT engines were assembled with the closed end facing in. This is mentioned in the Bentley manual. So if Hal's engine was converted from MT to AT without rebuilding it, this plug would "prove" this. Of course if the engine had been rebuilt, then the plug could have been re-installed either way. There was a long discussion on this in RAMVA a year ago, trying to decide why this was done. No consensus was reached, but here is my personal opinion: VW traditionally installed this cap with the closed end out. This creates a small chamber inside which will retain a small extra amount of oil which may hang around until the next startup. Since this chamber is at the far end of the engine from the oil pump it may provide a tiny extra bit of lubrication to the #1 cam bearing for the first few seconds. I don't really think this would have made a significant difference, but it probably didn't hurt anything either. Just outside this end cap is the spinning flywheel. If something happened to it you could imagine that it might come loose and wobble and wear thru the end of this cap, which would lead to a massive oil leak requiring teardown of the engine, but the MT flywheel is massive and stiff and seldom comes loose on its own. The AT has only a rather flexible drive plate, which could flex and fail in a number of possible ways; remember Leon's story. Turning this plug around gives a much larger safety margin in that area, meaning that most failures of the drive plate, drive plate bolts, or torque converter would never lead to anything wearing thru that plug so that this problem is not likely to require an engine teardown. Keep in mind that replacing this steel plug requires splitting the case. New cases no longer have the retaining groove for the steel plug; they use a rubber plug in a smooth bore instead. I haven't seen one of these myself yet. It seems like just a cheaper way to do the same thing, but apparently it works just as well. Has anyone out there had any experience with these? - Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ------------------------------------------------------------------- List info at http://www.vwtype3.org/list or mailto:help@vwtype3.org