I am in the process of doing an inspection and refresh on a motor from a 1982 300D. In pulling the oil pan, I found the part below. It looks like maybe a 1 inch rubber/plastic diaphragm that was stretched, torn and sucked into the engine, eventually ending up in the pan.

There are two numbers stamped on it: 3887 and 2072. Searching on 3887 brings up a hydraulic suspension pump, but this motor doesn't have one.

I have no history on the car the engine came out of other than it had about 200K miles, so I don't know if it was exhibiting an issue or if whatever this diaphragm came out of was already fixed. I suppose I could run it and see, but I'd rather be more proactive in tracking it down while the engine is out of the vehicle.

So: anyone have a clue what would have a 1 inch diaphragm as part of the oil circuit?

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