How to Install a Mower Blade


Your push-style rotary lawn mower cuts the grass with a rapidly spinning blade. After cutting all season, the blade can become dull, and running into small twigs and stones will make it worse. Installing a lawn mower blade is relatively easy. A single bolt usually holds the blade to the engine shaft.

Step 1

Take the lawn mower to a smooth, level surface in a well-lit area. Disconnect the sparkplug wire from the sparkplug. It should simply pull off.

Step 2

Put on your gloves and turn the lawn mower on its side. Wedge a wood block between the lawn mower and the mower deck housing. This will prevent the blade from spinning as you try to loosen the bolt.

Step 3

Turn the bolt holding the blade counterclockwise with an adjustable wrench. Loosen it up completely and remove. Remove the blade and put aside any washers that come off with the blade for reinstallation with the new blade.

Step 4

Position the new blade into place. Put the bolt and washers back on and tighten by hand. Use your adjustable wrench to tighten the bolt until it is secure.

Step 5

Set the lawn mower back upright and put the sparkplug wire back on.

Tips and Warnings

  • Failure to wear gloves when changing a lawn mower blade can result in severe cuts to your hands. The lawn mower blade is extremely sharp.

Things You'll Need

  • Wooden block
  • Adjustable wrench
  • Gloves


  • Blades Lawn Care: How to Install a Lawn Mower Blade
Keywords: install a lawn mower blade, adjustable wrench, spark plug wire, mower deck housing

About this Author

Robin Gonyo has been writing for several years now. She has a deep love for gardening and has spent a vast amount of time researching that subject. Previously she has written for private clients before joining Demand Studios. She hopes to share her knowledge with others through her writing.