I lived much of my life not realizing that gas has a relatively short shelf life. I figured it out by sending one of church’s mowers to the mechanic because it was running terribly. The result? He replaced the gas and it ran beautifully. The gas had gone bad sitting in the shed over the winter.
Common estimates say that after about 3 months, your ethanol blended gas (which is almost everything you buy these days) should be thrown away and replaced. If you put Sta-Bil or some other fuel stabilizer in it, you might get 6-12 months. The longer you store the gas, the more water that the ethanol attracts. Watered down gas is a mess for your engine to deal with. At best you’ll get decreased fuel mileage and power, but in extreme cases you can really mess up your vehicle.
It’s not a big deal in cars because we generally run through the tanks of gas pretty quickly. It’s a more common problem in lawn equipment. During the winter months, that gas is effectively rotting in your shed and gums up your carburetor.
To help avoid these problems, I do a few things:
- Whenever I fill up our gas can, I set a reminder to replace it in two months. The can is pretty small so I usually just pour it into my car’s gas tank when the car is already mostly full. I figure it can deal with a gallon or two of older gas mixed in with 10 gallons of good gas.
- The last time I fill up the lawnmower for the season, I use ethanol free gasoline. You can buy it from special gas stations, or you can pick up a can from the home center. It’s not cheap but spending a couple extra bucks to save yourself the headache of cleaning a carburetor is probably worth it.
- My weedwacker accepts multiple attachments so I can also use it as a leaf blower and an edger. It gets used pretty often during the spring, summer and fall, but even then, I hardly go through any gas. Rather than keep a small gas can with oil-mixed gas that will go bad before I use it all, I just buy the premixed ethanol free gas. It lasts “forever” and I don’t have to remember where I put the oil to mix in.
It costs a little extra but these simple steps can save you time, headaches and money.
P.S. It feels like I just wrote an eHow article. Ew.