So I finally got around to diagnosing (hopefully fixed) the clack/rattle/knock that would occur immediately upon start-up and when you turned the engiine off.

What I think was happening, was that the oil pipe was disconnected (it was) and was rattling around banging against the air can or whatever else might be down there.

So a couple of questions/observations:

1) some one had already added the third rubber bumper to the air can; the bumper that rests against the valve cover. Looked like a factory job, until I read the forum archive. The mechanic did a pretty good job, though I left a few washer's off in order to make reinstallation easier - aligning everything, etc.

2) Only two factory rubber air filter mounts?

3) The oil pipe was the definite culprit. I was able to reconnect it at the air can, but have no idea about how it's connected below (to the oil pan?). My question is that the oil pipe was "loose". By loose, I mean you could move it up and down an inch or two. This made it easier to align and reinstall the air can properly, just wondering if there is something going on farther down below that needs to be addressed.

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1982 240 D, 308,000 - 321,127 miles (sold)
1982 300 TD,166,500 - 226,000 miles
1998 E 320, 120,000 - 144,000 miles
2005 C 230 K, 26,000 - 77,000 miles (sold)