I had a science instructor back when I was a freshman in high school Matt and he told the class of an experiment he did by pulling a rope across an open gas can with a rag attached that was on fire. He said he wanted to see if the fumes were explosive. He said he took cover behind a trailer just in case it blew up. He told us that the fumes wouldn't ignite and that its not flammable.
I didn't believe him period! Sometimes its flammable and sometimes its not. But I treat it like it always is.
Like I said my only experience comes from what I've done and have much faith in that technique. As long as I'm the one "DEODORIZING" the bike tank I'll solder it.
A truck tank or diesel tank, no, I don't have any experience with those.
Years ago my girlfriends sisters husband, his brother took a job offer from him to work at a tanker shop in the mid west cleaning tankers. His job was to open the hatch of the tankers and go inside and swab them out. One night just the two brothers were working late at the shop and the younger who was inexperienced, was over by a tanker having problems opening the hatch when the other one just happen to turn around and saw him flick the flint to light the torch and yelled NO! One was blown through the wall and the one who flicked the flint to lite the torch was blown through the roof.
I remember it made the national news that night. In an attempt to save his brothers life the doctors as a last ditch effort, because he was so severly burned and the swelling so intense they slit the back of his legs from his heels to his buttox then the backs of his arms and his back.
It didn't help save his life, he died of Cardiac arrest from the swelling. He was only eighteen.
My advice to anyone who would attemp to weld, braze or solder, know what you are doing before you start or you could pay with your life. If you know nothing about it, don't attempt it. Gas and fumes are extremely flammable as we all know regardless of what the 'so called experts' tell you.
RPM