Thanks for all the replies.
Oil contamination is always a possibility, and yes, I do have what appears to be a very minor rear main leak, but I'm talking very minor. It also does not explain the high release point. I will check for any eccentric or other adjustment but cannot recall mention of one in the manual.
I hear what you are saying re an oil leak but as I only have the slight one mentioned above (which would be on opposite side of flywheel to clutch). No apparent transmission leak.
Interesting what you say about release point moving higher with wear. That suggests the self adjusting hydraulics don't quite. Also interesting that you mention the clutch can be worn out despite the gauge indicating otherwise. You may be right on the mark with your call.
It's a self made gauge (very easy to do). Most manuals give a diagram of the dimensions to cut it out from a piece of sheet metal.
I too agree that Haasman may be right.
I will check for any eccentric adjustment as you and Larry suggest. I had considered the hydraulics, but as Larry suggests (and from my previous experience with other cars with hydraulic clutches), hydraulic problems usually cause release problems, the opposite of my problem.
I guess while it is not a major problem, I will be gentle with it and hope that someone may come up with a definite answer. I will be mindful of any slip and not continue driving it if slip does become worse as I don't want to risk damage to the flywheel. I believe the dual mass flywheel as fitted to mine cannot be machined and must be replaced if damaged, something I would rather avoid. When it does become a problem that must be dealt with, unless I have advice otherwise, I will remove the transmission and replace the clutch. While in there I'll also do the rear main seal and front transmission seal. In the meantime keep any ideas coming.
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