Bare with me...I'm a new (and very happy) 1982 Vanagon L Westy owner...

My engine looks/runs/sounds great and recently had a COMPLETE overhaul
for which I have some questions about what exactly was done.  First,
however, I would like to know why my air filter is black and "appears"
as if was soaked in oil?  The engine idles high (1000rpm), but other
than that it seems to run in PERFECT condition.  The oil level is
halfway between min and max.  I'll put a list of what was done to the
engine and maybe someone could tell me what it all means and what may be
missing.

THANKS for any help.  Just curious about the air filter.