knotch/busted pimple on radiator filler rim

[damn240]

yeah i need to know if there is supposed to be a tiny knotch on the rim of the radiator filler hole. i've gone through 3 leaky radiator caps because this knotch digs into the rubber on the cap and bends them. it so fine and perfect though it looks like its supposed to be there. it sort of looks like a busted pimple, like a very fine tiny crater. i dont know!

thanks

[180fan]

got a picture? If i remember my radiator filler, there aren't any bumps on them.

[damn240]

sorry, no pic. i just went ahead and filed it down. everything is smooth now on the rim. i think that little bump was some kind of defect from the factory where it was made. its not the original radiator anyway, so its cheap crap.

thanks