Egene, you must use some type of cleaner even detergent, so that it washes the dirt and grease off your filter. Then let it dry naturally. PFFFFFFFf thats gona take forever, so i preheated the oven to about 120 degrees, and let the filter "roast" for a while. Then i used the hair dryer from far away and it dried in a couple of hours. Then i reapplied oil. It was like new, except i oiled it too much so it sucked up a bit up and gave a hell of a stench in the garage that lasted a few days but it was fine.