Even for the best of weed trimmers, the wear and tear can mount up and cause problems after awhile when it comes to smooth, reliable use. One of the bigger problems that occurs with many weed trimmers is a loosening or grinding of the normal movement range of the trimmer head. But rather than pitch the malfunctioning weed trimmer when this occurs, with a little work and effort you can replace the old trimmer head and have your weed trimmer working as good as new in no time.
Put on your protective gear. Gloves and protective eyewear are a must when tackling a do-it-yourself project of this nature.
Remove the spark plug wire from the spark plug on your weed trimmer if it is a gas trimmer. This will prevent any chance of getting a nasty shock or having the trimmer unintentionally starting while you are working on it. If it is an electric model, make sure the weed trimmer is unplugged before proceeding.
Remove the trimmer line spool from your weed trimmer. This is generally accomplished by simply pushing down on the spool and twisting it off of the weed trimmer. This will give you ready access to the trimmer head.
Remove the bolt holding the faulty trimmer head in place. This is easily accomplished with a good ratchet set. Determine the size of the ratchet head required via simple trial and error testing and then remove the bolt from the trimmer head and remove the assembly from the body of the weed trimmer.
Seat the new trimmer head into place. Place the new bolt into the empty slot and use the ratchet to firmly thread it all the way in until tight. Do not over-tighten or you may risk stripping out the threads and ruining your weed trimmer.
Replace the line spool. Press the spool onto the new trimmer head and twist until it snaps firmly into place. Spin the assembly around to make sure that there is no binding or catching.