when you say clean i am assumeing you mean the outside.......................simple green works good dishwash soap works too also a power washer will do wonders.............
What about the inside? I took mine off a while back to tinker around and oh man was I sad. Cleaned everything up best I could and put it back together, trying to forget I know what it looks like in there. Wish I had an extrude honing machine lying around.