I had 7 litres of petrol leak from the fuel selector tap thread onto a hot engine on the go. I stopped or rather was stopped (as it went putt, putt, putt), turned the ignition off as fast as I could, jumped off and ran across the road fully expecting an explosion to get me airborne as I bolted for it. Not to be. An eerie silence ensued. So, what is the flash point of petrol? How hot is a hot engine? How safe/unsafe is it to investigate the cause of the leak with a mobile phone in one's pocket?