Proper Oiled Air Filter cleaning
There's really nothing special in my cleaning process. I bought a second filter to allow me the time between changes for proper service. That's the key.
Here's what I do. For cleaning I put 1/2 gallon of simple green in a 5 gallon bucket and fill it the rest of the way with straight hot water from the tap. Put the filter in cone down and slap the lid on it for about an hour. The dirt will settle to the bottom and the oil will rise to the top. Pull the lid and drain off the oil on top. This way when you pull the filter up out of the water the dirty oil won't flow back into the filter. Stand the filter up on the cone end and let it drain and dry for a day or two. I don't blow them out or use heat to dry them.
Here's the trick. After the filter is dry I over oil the hell out of it. I even go back over it the next day to make sure I didn't miss any small areas on the ends.Then I put it in a plastic bag with the small cone end down and place it back in the box. Throw it on the shelf and forget about it until you need it. When you come back for it in a month or two you'll notice that the excess oil has drained out into the plastic bags. The filter saturation will be dead even all across the filter and it will look brand new. This will give you perfect coverage and the exact same oiling every time.
Nothing to it...