when i get a filter, and before i even put it on, i open it up and take the "filter" part out. also Odonnell filters come with NO FILTER in them. also Hotbodies D8s dont even come with an external filter. 99% of the tanks come with a filter in the tank. i wouldnt worry about it especially since you bought it used, he must have done it for a reason. also when i first started i had to filters clog up and cause my engine to run very lean.