is every engine gonna get a little dirt in it each time you run it?? i mean if if i play in alot of dirt and after an hour i take the filter off and around the inside bottom seal it has dirt their???? is it cause i'm putting the tie around it too tight( which i didn't think i did but who knows) or is this normal or am i still just a paranoid newbie LOL it has and indent all around the inside bottom part of the filter about 1/8" up from the very bottom, i didn't really see any dirt higher than that, but below it was alot of dirt, i'm guessing, hoping the indent is where it seals at and below doesn't matter???