I was wondering what you do to maintain your canister air cleaners. I was searching and found that people are saying they can get 1000 hours out of them before they change them out. But I have hard time believing that you have to do nothing to them for 1000 hours of use. By the way it is on a 23hp Kawi. (don't know if it makes a difference with the brand) The mower has just over 100 hours now and is just starting to get some color to the large outer filter. That is a big difference when compared to my last mower with the tradition style filter. These things are nice. As always, thanks for the input.