Placo, it would be my. . .
pleasure. If you're in SD, left me know. We can get together.
Re a 'weak' lifter: the picture in my web page under menu #19 is one of those critters. It can be pushed by hand (finger) and it starts to collapse. As my tech tells me, it's not supposed to do that.
Trying to find a 'bad' one on a M119 engine is difficult at best. I've seen where a feeler gauge is used to push under the lifter/cam surface. If it goes 'easily', it's a candidate.
Re the chain tensioner: I can't see where that would cause a problem just at startup. If it's loose (stretched), it's loose all the time.
Regards . . . . JimF
'94 S500 Cpe
Visit my Mercedes Web Page