Lawn Mower Blade Maintenance

Mower blade maintenance is just as important as engine maintenance when it comes to ensuring equipment performance and longevity. Dull mower blades can unevenly rip or shred grass, leaving it torn, dry and susceptible to disease. Replacing or sharpening the mower blade will ensure a clean and healthy lawn.

The equipment operator’s manual will provide detailed steps for mower blade replacement and sharpening. Prior to performing any blade-related maintenance, ensure that the fuel tank is empty and wear hand and eye protection.

Replace your mower blade in 9 steps:

  1. Read your equipment-specific operator’s manual for guidance.
  2. Remove the spark plug wire and battery pack or key.
  3. Clean the deck of grass and debris so you can access the blade. Use a garden hose or pressure washer to wash away the material. After spraying, remove any remaining clumps of grass that may interfere with the blade by using a stick or other tool – never use your hands or feet.
  4. Tip the mower on the carburetor side and block the blade with a piece of wood so it doesn’t move.
  5. Remove the nutter bolt that holds the blade onto the mower.
  6. Inspect the blade for cracks, nicks or dents. Replace the blade if it’s worn, bent or dented beyond repair.
  7. Sharpen the blade with a file or a bench grinder if your blade requires more serious repairs. The blade shouldn’t be too sharp and thin or it will be prone to damage.
  8. Cool the blade with water as your sharpen because heat will weaken the blade.
  9. Reattach the blade to the motor spindle.

Check out this video, for more detailed step-by-step guidance.

Once your mower blade is sharpened or replaced, you can return to crafting a beautiful lawn. Remember to never cut more than 1/3 of the grass blade during your cutting sessions.
For more lawn mower engine or other outdoor power equipment maintenance and repair tips, visit the Support Tab on

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