wd40 to fix a tire?

Not quite sure what is going on here:

This is a technique for setting the bead of a tire and can be done with many sorts of aerosol petroleum products. When ignited, the substance, WD-40 in this case, combusts and rapidly expands in volume, forcing the tire bead back into the rim or the wheel. This will not inflate the tire to correct pressure, but provide enough pressure to seat the bead so you can inflate the tire by other means.

Sometimes it will OVER inflate a tire if you use too much. It does take some care to avoid all the potential bad endings.

It is a really neat trail trick or back 40 farmer's trick (back before cell phones). Just like welding with jumper cables.

WD-40 belongs in every tool kit, along with a roll of duct tape.
(Of course, the tool box would be a 5 gallon plastic bucket.)

The "WD" stands for "Water Displacement".
I've known farmers to use WD-40 to 'cure' scaly leg in chickens, amongst other things.

I have had good luck using a tie-down ratcheting strap to clamp and slightly pinch inwards the center of circumference of the tire dead center of its tread, this will bow outward
the side walls of the tire, then bounce it off of the ground a couple of times and try to see if you can get it to take air ! This trick does not really cause a dangerous amount of
but should be done on the truck with the Truck up on jack stands, and never with the use of Ratcheting tie down straps ! Big Al !

I've seen starting fluid used. Sometimes on old rims and tires, they use a goo to help with the seal. I think the idea is to heat the bead and goo at the same time. Tire shops that have plenty of high pressure air, can usually get a good seal by jostling the tire about and then hitting it with a rubber hammer as it expands over the bead. These back yard tricks are used by those with lower volume air systems.

The tire isn't being "fixed", as in hole patching. It's just an expedient way to get it into a good seal position, so that air being pumped in doesn't escape through the crack. The hot gas will quickly cool, so the air would be immediately attached and the pressure adjusted before the tire has a chance to pull away from the bead.