Bobcat 642 newbie ?

[JAG642]

I have a 642 that I just bought and worked fine when I test drove it. Did some work (30 mins the other day and now its dripping a bunch of oil out of the crank breather-blow by (I believe). It comes up from motor via hose to a plastic shroud with foam filter in it. I changed the oil and re-filled with 4 quarts...still is dripping. I noticed in the very dirty oil some metal dust too. No ticks in motor and plenty of power. Anyone have any advice whats causing this. Thanks