Originally Posted by Col.Klink

You should have a Plastic Screened pre filter and then the big round oil filter and in the bottom of canister should be a round washer on top of a small sring .The Plastic goes on the top with the large vented plastic piece towards the top or facing towards the engine. Those are a ***** even when brand new off the show room floor and takes a bit of finageling to get completely out . You may have to jack up the engine just a bit to clear the frame better and be Damn sure to use a rounded o ring not a flat one and be sure it(The Canister is seated into the housing well before tightening it as it is very easy to get it crooked .