I cleaned mine this week also. I blew it out with compressed air and it looked good enough to re-install... but reading the manual saw it was washable so I stuck it in a 5-gal bucket with Dawn and it turned the 3 gallons of soapy-water absolutely BLACK! I did it again with fresh water and it got that pretty dirty also.You know they are washable? I soak mine in a bucket with Dawn dish wash detergent, rinse in clear water and let air dry. beats 35 bucks for a new one.
Anyway, I know they say not to, but I also blew out the secondary but nothing came out of it so I reinstalled it after wiping the entire filter-box/cylinder out with a damp rag.
It’s surprising how much dirt these things capture even when you think you’re using the tractor in a non-dusty environment. Lots more air goes thru a tractor than fuel so I think its a good idea to keep up with these.