Well, I pulled the clutch last night and found out why it was locked up to the flywheel. You may not believe this so I took pictures.
The pressure plate looked clean and undamaged. It came off easily and there is clearly good life left in the pad lining based on thickness, but the clutch pad itself was literally stuck hard to the flywheel. It did not fall out as the manual warned might happen. I couldn't even pry it out with a sturdy plastic trim removal tool. I had to get my biggest screw driver and pry it away from the flywheel face. It finally "peeled" off like it had been glued on.
. So, the clutch was bound to the flywheel no matter what the pressure plate was doing, and believe me, before tearing into this I was pretty forceful rocking the car back and forth while in gear, with the clutch pressed fully in, just in case I could break loose any corrosion as others had reported success with.
So,
Nothing is broken or worn out at all, but it is all contaminated with a thick grease layer! I mean a layer of that thick stiff black gooey pasty old grease like you would find around a 50yr old differential fill plug. Very sticky, definitely not oil, even old oil. I took a couple pictures of the saturated clutch disk where you can see moist beads of sticky black substance (just on the flywheel face) and on the flywheel can be seen a bead of black goo which I could smear with a lot of effort. On another area I cleaned it off with alcohol to show the contrast.
I have never heard of this and hope some of the experienced folks on the forum might have and idea how it would happen. I'm not aware of any path for contaminates like that to get into the flywheel housing area. It's the only place I found grease too. The rest of the housing and flywheel are pretty clean and there isn't any sign of build up or contaminates at the bottom.
All I can come up with is that this car has a history with grease. My dad truly believed in maintenance, probably too much. he would give each zert a pump of grease every time he changed the oil. there were some nooks and crannys in the suspension arms where I scraped easily 1/2 inch of old grease. The layer of grease on everything did a wonderful job preserving the car, no rust anywhere, but I'm wondering if somehow, some way, grease made it inside the clutch area. I just don't see how, but thats all I got.
So I'm cleaning everything up today and then replacing all the usual parts with new ones, but would really like to know if there is something someplace to check for root cause of this?
I already ordered a new pressure plate and clutch pad from Mercedes Classics, pretty good deal right now BTW, compared to some of the usual suppliers.
While I have it torn down I'd appreciate any advice or ideas of what to check or do while I'm in there.
last one is just another crappy picture of the eclipse that happened just as I was discovering this issue. Maybe related ;-)
thanks!
Mark