I'm looking at making my own refinary in the back garden, has anyone made one yet. I have looked at most of the good sites on the web about this but it would be good to hear someones opinion who has already done this. I wanted to know things to look out for when building a refinary, things that people may have, in hindsight done slighly diffrently perhaps. Initialy I am thinking of starting with unused oil just until I get the hang of things. So far I have managed to source a used emersion heater, header tank, central heating pump and a 40 gallon drum (going to use this for storage). What I would realy like to know are what are the pitfalls to look out for, has anyone had any major disasters? I am going to be putting this into my 96 300TDi disco, has anyone been using bio in a 300TDi?