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How to Change the Primer Bulb on a Weed Eater

By Mike Andrew ; Updated September 21, 2017

Before starting your Weed Eater’s engine, you must first prime the engine by drawing a small of fuel from the fuel tank into the carburetor. Priming the engine is accomplished by repeatedly pressing and releasing the primer bulb. If your primer bulb leaks, cracks or malfunctions, you must replace it before the next time your start your Weed Eater.

Buy a new primer bulb. Be sure to select a primer bulb that is compatible with your make and model of Weed Eater. Refer to your manufacturer’s manual or official website to learn the correct size and type of primer bulb for your Weed Eater. You can buy most types of primer bulbs at major hardware stores or lawn care shops, or you can order the bulb directly from the manufacturer.

Remove the outer cover or casing of your Weed Eater to reveal the entire primer bulb assembly. Locate the screws securing the outer cover to the Weed Eater, remove the screws and gently lift the cover off the Weed Eater.

Clean the area around the primer bulb. Wipe away loose dirt with a towel. Apply degreaser to the metal plate that attaches the primer bulb to the Weed Eater. Allow the degreaser to loosen the grime for several minutes and blow the debris away with compressed air.

Remove the screws that attach the primer bulb assembly to the Weed Eater and set them aside. Insert the head of a flathead screwdriver between the bulb plate and the Weed Eater and gently lift the bulb plate up. Remove the primer bulb and bulb plate.

Insert the new primer bulb assembly into the slot on the Weedeater, aligning the holes in the Weedeater with the holes on the bulb plate. Insert the screws in to the holes and tighten them until the bulb assembly is secure.

Replace the outer cover of the Weed Eater.


Things You Will Need

  • Flathead screwdriver
  • Phillips screwdriver
  • Primer bulb
  • Degreaser
  • Towel
  • Compressed air


  • Do not over-prime your engine, as this can cause the engine to flood. A flooded engine is difficult to start and will perform poorly. Refer to your user’s guide to learn the proper number of times to press the primer bulb when priming your engine.

About the Author


Mike Andrew has written business and legal articles for "850 Magazine" since 2008 and covers college football for several websites. Andrew is a freelance writer, attorney and music producer based in Florida. He received his Juris Doctor from Florida State University.