Sugi,
Thanks for the thorough description of stem seal and guide issues.
On my 4.5, obscene quantities of smoke pour out the tail pipe on most every start-up. The guides/seals must be so badly worn that oil just dumps into the cylinders. Also, there is usually very visible blue smoke wafting out the back on leaving a stoplight. My friend on following my car commented "There's so much blowby that George Bush could declare your exhaust system a natural resource for drilling exploration"
I guess its high time for a compression and leak test (probably like a seive).
Well at least I only paid 500 bucks for it and got my moneys worth out of it but I'd hate to put an old benz to death.
I don't think it smoked that badly when I got it a year ago. I'm beggining to wonder if the leaky radiatior which leads to occasional high temps has made matters worse. It never boiled over but got almost to the red a couple of times. I watch it like a hawk and drive it easy.

__________________
63 220S W111
76 300D W115
2013 VW JSW TDI M6

previously-
73 280 SEL 4.5
86 300E 5 speed
2010 VW Jetta TDI M6