Why You Can’t Use Winter Gas in Summer (or Vice Versa)
If you have a snow blower, lawn mower, or other gasoline-powered device, chances are you also have a canister of gasoline to power it. But if you bought this gas in the winter and plan to use it in the summer, or vice versa, you may find that your mower or blower is not working as it should. Why not? It’s all about the gas.
Winter gasoline has a higher RVD
You already know how water reacts to heat and cold, right? If you put a bowl of water in your driveway in the summer, it will evaporate pretty quickly. Do the same on a cold day and it will slowly evaporate, if at all.
Gasoline also depends on temperature. On a cold day, gasoline must be volatile enough to turn into steam when the engine is started. Winter gasoline has a higher Reid Vapor Pressure (RVP) so it can vaporize enough to do its job even when it freezes.
For these reasons, you’ll want to use winter gasoline in your snow blower or generator during the winter. If you save summer gasoline for winter use, you may have trouble starting your devices and your engine may misfire.
Summer gasoline is more economical
With summer gasoline, the opposite is true: it has a lower DPR, because in the heat it can evaporate too much. This can cause engine problems and can also lead to emissions.
The EPA sets an RVP limit for gasoline sold during the summer (June 1 to September 15) to avoid these emissions. In addition, individual states may have their own emission standards and RVPs .
Summer gasoline is not only better for lawn mowers in summer, but it’s also more economical , so you can mow more grass with the same amount of fuel.
Gasoline lasts only a few months if left untreated.
There is another problem with storing a can of gasoline from season to season: the material is about to expire!
Gasoline is usually enough for three to six months from the moment it is filled. Storage conditions will affect this: In the summer heat, it will not last as long. The type of gasoline also affects the service life. Summer gasoline is often a mixture of gas and ethanol and only lasts one to three months.
If you know your canister won’t run out of gas anytime soon, you can treat it with a fuel stabilizer like Sta-bil to keep it running for about two years. It won’t rejuvenate a gas that’s been idle for a while, but you can add it to a new can of gas to make sure it still works next season.
What about that old can of gasoline that you just realized is now useless? You can take it to a hazardous waste disposal center or look for hazardous waste disposal facilities in your area. We have more information on how to dispose of old gasoline .