--------------------------------------------------------------------- While walking up to the entrance of a radiator repair shop, I noticed a Pick-Up running at fast idle with a hose connecting it's tail-pipe to the filler neck of a gas tank. It kinda shocked me at first glance. Ya know... I had to ask about the setup. “It's a common procedure to evacuate fumes before repair & we’ve been doing it for years”, he said, “I only had one blow up”. Curiously I asked, “How long do you let the exhaust idle through the tank?” “After the first one blew, we now run it for at least… 30 minutes.” He said, with a torch in his hand. I was an intrigued thirteen year old then and it was the early 70’s. I never saw this since or even thought of this procedure ever again until, I looked at your thread. Great ingenuity! The things you remember,