As I described in my article called A Little Advice About Storing Gasoline For Use In Backup Generators, when gas gets old, it loses its volatility and doesn’t work as well.
You may have some of this in your possession and be wondering how to dispose of old gasoline. Every year, tons of gasoline is simply tossed onto the ground by people who are either ignorant or uncaring when it comes to ecology. Gasoline is considered a hazardous material and it should never be disposed of by dumping it on the ground, in storm drains, in the trash or down toilets. Not only is this irresponsible, in most places its often illegal!
Depending on how old the gas is and how much it has deteriorated, you may be able to recycle it by diluting it with fresh gas and using it to power things like old lawnmowers, chainsaws, or even old work trucks. You will have to use your own best judgement as to whether or not you want to dispose of old gasoline this way but I can tell you that this is how we do it and we haven’t had any problems.
I should point out that we NEVER use old gasoline in engines that don’t have a fuel filter on them because we don’t want to gum up the carburetors. Old gasoline can have contaminants like rust, dirt, and even water in it. Inline plastic fuel filters are cheap and easy to replace but cleaning a carburetor will take a bit more work. We install these filters on all of our power equipment engines as a precautionary measure but like I mentioned, we’ve never had a problem recycling old gasoline in this manner.
Another option is to look in your phone book under the yellow pages section labeled “waste management” or “environmental and ecological services” for a company that is in the business of properly disposing of hazardous materials. You’ll likely have to pay a few dollars if you want to have them dispose of your old gasoline but the modest fee that you may have to pay is much less than the price that our ecosystem will pay if you do something like dumping it on the weeds in your yard.