1975 and earlier MBs required vave adjust at every E service, so the VC gaskets were always changed. With the advent of hydraulic lifters in 1976, nobody ever pulls the valve covers anymore. I reccommend VC gasket replacement and inspection of the valve train every 30k. While the covers are off check condition of oiler tube holders and check cam timing. If timing is late by over 8 degrees, you are living on borrowed time with that engine. One day that engine will stop and you will be looking at a repair bill for more than the car is worth. Why did you run DELO in that car? DELO stands for Diesel Engine Lubricating Oil. I live about 80 miles North of you and I run plain old 20/50 dino year around. I don't even have a favorite brand as long as it is a name brand. Between my fleet and client's cars I have logged over a million trouble miles.

Peter

__________________
Auto Zentral Ltd.