This is the filtering setup I have in the garage.  I dump the
oil into the barrel and let it settle.  The big green cannister
holds a 5 micron filter bag.  There's a pump behind it that pumps
oil up from the barrel into the top of the filter.  The 
filtered oil comes out the hose connected to the bottom of the
filter cannister.<br>
<br>
The oil splashes you see on the wall... well...   what can I say?
I blew the little plastic plug out the top of the filter 
cannister, and enjoyed a beautiful golden-colored geyser.  Upon
double-checking the manual for the filter cannister, I
discovered that it says (in big bold letters) to be sure and put
a pressure gauge into that hole, or plug it with a threaded
plug.  I understand why it says that now.  :)