In a homeowner's relentless pursuit to control weed growth around her property, a weed trimmer is a valuable asset. Over a trimmer's life of use, frequent maintenance is required, including changing trimmer line or replacing blades. Every now and then, a line trimmer's trimming head will need replacement due to wear and tear. A trimming head might stop spinning or might have trouble rotating smoothly when it needs to be replaced. You can normally notice this problem when a weed trimmer fails to cut weeds or when a loud grinding noise is produced when you try to use the trimmer. Though numerous models of weed trimmers exist, removing a trimming head is basically a universal process.
Unplug the weed trimmer or, if it is gas operated, turn it off completely. Place the trimmer on a workbench or other flat surface to change the head.
Clear grass clumps or other debris from around the trimming head. You can use a stick or a rag to clear the debris away.
Look for a locking mechanism on the side or near the trimming head. Most weed eaters do not have a locking mechanism, but a few will. This is recognisable by a small switch or button near the trim head. Unlock the head by depressing the button or flipping the switch, then pull off the head. Other trimmer heads unscrew. You might unscrew the head completely without removing the trimmer line spool, or you might have to unscrew the trimmer line screw first. If no locking mechanism is present, no screw is present where the trimmer head attaches to the shaft, and the trimmer head itself doesn't unscrew from the shaft, simply hold the trimmer in place and pull off the trim head.
Never attempt maintenance on a trimmer while it is in operation. Always ensure that the trimmer is turned off completely prior to changing the head.