There was a thread somewhere on these forums on that exact question (shelf life of opened and sealed cans of Coleman fuel) and the general consensus was that the general life is LOOOONG.


As anecdotal evidence, I can say this: My mother recently asked me to come clean my old boyscout stuff out of her garage. Included in the old boxes was an ancient MSR backpacking stove and 2 MSR aluminum fuel bottles. One was full, the other about 1/3 full. They had been stored thus since my last backpacking outing as a scout, probably around 1991 or so. (So 17 years, as this story dates from 2008.)

The gaskets on the bottles were aged but still holding, as far as I could tell. I replaced the gaskets, then decanted the fuel into a single container. Then I added a little *new* fuel to the bottles and agitated them, to dissolve any varnish that might have formed from evaporation of the old white gas, (just in case) then topped the bottles back up with the *old* fuel, leaving a little headspace, and then burned up about half of each bottle on the old MSR stove. The fuel burned as clean as normal, with no unusual sooting or flame color.

Then I went through and did a full maintenance on my stove, and I found that aside from a few dried gaskets, it looked exactly as it had nearly two decades earlier. In particular, there was no unusual clogging or gunking around the fuel jet or anywhere else that I could see.

I've since used that stove on a snow camp (I usually backpack with an alcohol stove now, except in extreme cold) and finished burning up the rest of the old fuel, and I still haven't noticed that it burned any differently than new fuel.

Now granted, the MSR aluminum bottles are a superior storage vessel to the steel cans from the store, but I still think this speaks volumes to the stability of the fuel. Rust through of the steel can (outside to inside) is probably a bigger concern for long-term storage, but I wouldn't worry too much about fuel contamination, even with some airspace above the fuel, as long as you can keep the container sealed.