To my surprise I found "liquid" in the gas tank.  Smells like weak gas, yellowish in color.  I was told by previous owner that tank was fairly new and empty.  NOT SO.  My question is removing whatever the liquid is.......what is the best way to remove it w/o removing the tank.  I have a 12V syphon pump.  Once removed I can put vinegar and baking soda in it then insert  air compressor hose into the tank.....release lots of air bubbles to agitate the liquid,  then syphon it again. Thoughts and ideas.