K&N Maintenance

[rrausch]

I just cleaned and re-oiled my K&N (stock box) Air Filter after 40,000 miles. I think I've got it figured out how to properly clean, oil and re-install the thing. Here's what I did.

First I bought a K&N "recharger kit" for about $7 from Pep Boys.
I removed it from the box and brushed the filter first with a soft-bristled paint brush and it was amazing how much black crud came off it. After I brushed as much off as I could, I sprayed it with the K&N cleaner and let it sit for 10-15 min., then ran luke-warm (Not Hot) water through it from the clean side, reverse-flushing it. (Hot water will shrink the cotton.) Also, K&N says any good detergent will work, but of course they "recommend" theirs.

I made sure all the crud was out of the pleats and repeated the cleaning process just to be sure. I then let it sit to dry near a warm air register but again not so that it would get hot--didn't want to shrink the cotton.

When I re-oiled it I used about 1/2 the 6.5 Oz. spray can. Here K&N is very specific. USE ONLY K&N OIL. Don't use anything else to re-oil it--and NEVER run it dry. When I put it back in the filter box I bedded it into the stock filter box with a little Syl-Glide Silicone grease.

I got a little worried, the next day, that I had used too much red oil, so I e-mailed K&N and was promptly answered by an engineer from the tech dept. He said our Dodge/Cummins (stock box) rectangular filter is charged at the factory with 3.5 Oz. of oil. So I figure about 1/2 the 6.5 Oz. can is about perfect.

Drying it takes some time. Just let it sit and dry, don't try to speed things up with a hair dryer or anything.
Although each specific task didn't take much time, 4-5 hours probably elapsed while I did this job--most for drying. Next time I will pull it late in the evening and let it dry overnight.