So does that plug just pull out?
So This is way to weird that you are describing the the EXACT same issue that I was fighting for over a year in my machine …. And I DO Mean EXACTLY !!! ….. LOL
The plug in the bottom is threaded in …. Careful it's a Plastic Tank so try and be careful NOT to strip the threads !!! …… But that stinking hole is TOO Damn small to get anything like a potential Floater out thru there ….. YES it will allow water and dirt contaminants (finer stuff) but forget about anything like a leaf that got in there because the fuel cap got left off as I do regularly … LOL …..
I some how had my issue go away on it's own last year, but my clogging only happened once my fuel tank level got below half full …… When I drained my tank i had the front of the machine elevated ….. I used my gooseneck trailer beaver-tail & ramps, drove up far enough to get the front elevated and the butt end up so I could still crawl under the back, and remove the steel cover and then the plug (it's not that easy) and to have the machine high enough to get a 5 gal pail under to catch any fuel & debris that would hopefully wash out ….. Keep in mind that I also had my Tidy tank with the fuel pump to splash fuel in after it drained to wash out any loose stuff …..
After that whole process I still had a floater in the tank and had to deal with the plugging of the pick-up in the tank Exactly as you described ….. Cheers & Good-luck !!! …. GK