Popcorn smell sounds like oil to me....... After valve seals go, valve guides and valve seats will soon follow - especially since the slow lane is out of the question. Figure the 240D engine might have lasted for another 100k miles if seals were immediately replaced when oil seapage/burning was first noticed and the car was not being abused. Sorry dnewbie, but am thinkin 1976 oil burning 240 engine driven at 90mph will not last long.

Leatherman, granted i meant crankshaft pulley instead of flywheel... What exactly is wrong with measuring chain stretch as illustrated above?