Well, I pulled the carb this morning and took out the float and inlet needle to get to the brass jet insert. I noticed the needle no longer has a rubber tip. Are these needles all metal with a rubber coating over the tip? I thought they were different than the all steel needles, and that the rubber tip was separate from the body of the needle. Is it possible our gasoline has so much ethanol in it that it dissolves the rubber over the course of half a week (Tuesday, when I bought a new needle and replaced it). I used Briggs and Stratton part number 231855S which is the rubber-tipped needle. Anyone ever hear of this happening or had any experience with it happening?