If this is happening due to the change in temp, you’re going to have to vent to atmosphere (open the container) and then seal it when the temp is at its coldest. That way, your vapor pressure in the container is the lowest it can be. If you’re able to do this, the vapor pressure will be at its lowest and your container won’t be messed up when the temp rises, as the vapor pressure will cause expansion and not container retraction. My guess is there’s some stupid built in check valve that opens at a certain pressure in the safety/complicated/nanny pouring mechanism, negating all the advice I’ve outlined above and will still lead to container creasing.
I try to keep mine full, and store in a cool place, with the vent closed. No problems. The empty ones I leave the vents open. Never had a problem with the 5 gallon ones though, probably thicker plastic. The one gallon containers for my push mowers give me the most trouble when they are outdoors, and the heat gets to them.
I bought three 5 gallon plastic gas cans and they're much heavier duty than the cheaper cans. I do have older 2 gallon cans and they've never done this.
Yes, that would work, but keeping it full would require me loading up a half-full can and driving it to town to top it off every time I fill my mower. That sorta defeats the purpose of storing gas at home. And keeping it empty means I don't have any gas LOL.
Where do you actually find these? My aforementioned gas can, it has a vent like this but that part may not last forever. It's started to have bits of it chip off from thirty-something years of UV exposure.
