Tools that run on gasoline like lawn mowers, string trimmers, hedge trimmers and leaf blowers all need to have the gas drained from them over the winter. If you leave the gas in over the winter, this will reduce the life of your carburetor and lead to your tools being ruined. To drain the gas, just tip the tool over an open gas can and drain the gas into the can. Then, and this is the key, start your tool to get all of the gas out of the gas lines. Run the tool until it dies. Then you know that all of the gas is out of the line and your tool is ready to be stored for the winter.