One of the most crucial mistakes people make with lawnmowers and other outdoor power equipment, is to leave old gasoline in the fuel tank over the winter.  When I worked as a small engine mechanic, you could bet, every spring our shop would be filled to the front door with lawnmowers that wouldn't start or ran rough.  Preventing it is easy, and I'll tell you about 2 ways you can ensure your lawnmower (or other outdoor power equipment) will start right up in the spring.

Method 1 - Drain the Fuel

This is the cheapest method but it does involve getting some tools out and getting dirty (not very, just a little!).  For lawnmowers, first step is to empty the fuel tank.  Easiest way to do that is to resist filling up the fuel tank all the way near the end of the season.  When the time comes to winterize your lawnmower, start it up and let it run until it runs out of fuel.  If you happen you have a fluid extractor, you could use that instead. After the tank is empty, we need to make sure there is no fuel in the carburetor.  Most Honda (and their knockoffs) have a little bolt on the bottom of the carb bowl.  Grab a plastic container and place it under the carb, and using a 10mm wrench you should be able to remove the bolt holding the bowl on.  Use one hand to keep the bowl secured the carb, while you losen the bolt with the other.

You should get a few drops of fuel, plug the bolt back in when the fuel from the carb is drained.  Now that everything is back together, time to store your lawnmower in a cool dry place, like your garage for the winter.  Try to resist leaving it outside, in the rain and snow, that can cause problems with rust.  When springtime rolls around, fill up your lawnmower with fuel and it should start right up!

Method 2 - Using Aspen Fuel

I've tested a few fuel additives/substitutes and the best would have to be Aspen Fuel.  This is the easiest method to winterize your mower, but it requires a little bit of hunting down a supplier for Aspen Fuel.  It's not readily available in the big box stores, so check your local equipment rental store and see if they stock it.  When the end of the season is near, fill up your lawnmower with Aspen Fuel instead of gasoline.  You can use your lawnmower as normal with a full tank of Aspen Fuel for the last few cuts of year.  Then store your lawnmower, again, in a cool dry place.  In the summer you can use your lawnmower as normal and just fill it up with gasoline.  Aspen Fuel is free from many of the impurities in gasoline, so it can be left in your lawnmower over winter, and then mixed with gasoline in the spring with no side effects.  Simple!

What About Fuel Stabilizer?

Fuel Stabilizer can work, but I would not guarantee it as much as using Aspen Fuel.  Gasoline contains many impurities and additives, mixing that with more additives from the fuel stabilizer, is a big like putting make-up on a pig.  It's still a pig no matter how you dress it up!  One of the downsides to gasoline is the addition of ethanol. Ethanol absorbs moisture in the air, therefore water bubbles will start to appear in your gasoline, typically at the low points of the fuel system such as your carburetor intake port.  That can cause rust particles to form and clog up the jets inside the carburetor. 

That's why I recommend using Aspen Fuel, or if you know a similar product, let us know in the comments below.

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