The roll looks loose in the canister when you want to remove it after some use.
Some people think that oil is able to pass down around the element and thus oil will go through unfiltered. The element goes into the cannister tightly but when it is ready to be replaced it appears to be quite loose. This is normal, and just as well, otherwise it would be difficult to remove. The downward pressure on the roll is quite considerable. If you calculate the area of the top of the 4 inch diameter roll at 12.56 square inches and multiply it by 65 PSI, which is a common oil pressure, you will arrive at a figure of 816 pounds downward pressure on the roll; over a third of a ton. This pressure is reduced by the amount of oil that is able to seep through the roll. That still leaves a very large force exerted down on the roll. This pressure is able to reduce the length of the roll whilst it is in operation, and at the same time it increases the area of the roll. If you watched the roll performing under pressure, as we did, in a transparent cannister, during the development of the filter, you would see how it operates. It was quite remarkable to watch the height of the roll diminish and the diameter expand tightly against the wall of the 3/4 inch thick, clear-perspex cannister we built for the test. Toward the bottom, the roll developed crinkles, which actually helped to impede the flow of oil through the element. This process was one of the claims in the original patent of the paper roll filter. The proof of this process is the deep indentation created on the base of the roll during use. If you ever pulled a roll out and it had no indentation, caused by the element rack, at the bottom, then you would know that oil was bypassing the element.
To install an element correctly, all you need do is push it down firmly onto the bottom, centre seal, using the palm of your hand. It is not important to worry about the outside edge of the roll. The oil pressure will certainly push that firmly down, once you start the engine.
We do not attempt to hold the user hostage to using our elements. We have therefore used a standard element size that is accepted within the industry and our elements are interchangeable with Frantz, Kleenoil and some other filters. You are assured that you will always be able to access elements to fit your Jackmaster Filter.