After a time don't forget to take a look at the seals in the bottom of the oil canister. I finally got around to changing mine, they were almost as hard as the aluminum case! I got an old canister to try, and after filing a notch in a punch (to make better contact with the little metal ring holding it in place) I was able to punch out the metal ring, and replace the bottom gasket and the small o-ring that is inside the metal holding piece. I did it by inserting the punch from the bottom of the oil filter housing, so you can make contact with the metal ring. I worked my way around, just tapping, tapping, tapping, then perhaps a bit more forceful whack, and it popped right out. It is easy then to use the the punch to reform the metal, if you deformed it all, and then fit it back together.