I have been using these fillers on petrol for a couple of months with no trouble. I only use mine as a filler with the brass pipe inside the fuel tank reaching to the bottom, so the filler can also be used to drain the fuel tank. Then I block off the filler's second nipple that would normally go to the carb with solder, as I prefer to feed the carb on a direct line from the fuel tank clunk to the carb, this way I need not worry about the filler failing, or pulling air into the carb. I then use a third line into the fuel tank with the brass tube inside directed to the top of the fuel tank which is then the 'full' over flow line and vent. So far this has worked well and keeps my fingers from getting covered in petrol.

zlinman