Originally Posted by S-Class Guru

The valve cover has standoffs or pedestals on the bottom where the bolts come thru. These make contact with the head to allow secure tightening without crushing the gasket. I thought I had always been good at not overtightening the cover bolts, but I discovered the rear pedestals had actually worn down over the years, and normal tightening began to result in crushing and tearing of the gasket.
I surmised that on the 103 engine, the valve cover was actually sliding back and forth on the head a tiny bit during heat/cool cycles, and over 20 years slowly wore the pedestals down. Simliar to the head gasket tearing between the block and head after thousands of heat cycles.
just a theory, but I don't have another explanation. Now I very gently snug the rear bolts, but still get a pretty mashed gasket after awhile.
DG