On my 82 240D, the power-steering filter is held down by a heavy spring, which in turn is held in place by some sort of "press" or "clip" fitting that is pushed down the threaded rod which holds the lid on.

How do you remove that "clip" fitting? That is, without destroying it?

Thanks,

It probably not the same but on a 87 SDL the clip and threaded shaft unscrew together as one unit from the bottom of the resevoir!Unscrewing it frees the spring holding the filter down.