I've used original JB Weld for years to fill holes in carbs, etc. Time constraints at Cubfests convinced me to switch to the 5 minute Kwik Weld. At the Louisiana Cubfest the question was raised about whether it was gas resistant or not. I emailed JB Weld and got the response back that the original is if the gas has less than 10% ethanol. He suggested using the JB Tank Weld. I've not heard from anyone that their repair with JB Weld has failed/leaks, but wanted to put this out there. I may make a small wafer of each and immerse in gas with ethanol to see what happens.