Lawn Mower Blades

A sharp lawn mower blade is important for keeping your grass healthy and making lawn maintenance quick and easy. A new lawn mower blade can improve performance for all mowers, including riding mowers, high lift lawn mowers, and those that take mulching blades. Regularly replacing these parts will improve the look of your lawn and your mower’s clipping ability.

When should lawn mower blades be replaced?

Replacing lawn mower blades on a regular basis will improve the function of the lawnmower and the appearance of your lawn. Poor clipping performance, uneven grass, and dead spots in your lawn could all be signs that it is time for sharpening or replacement. Visually check your mower blade at least twice a year to look for the following sure signs it is time to replace your lawn mower blade:

  • Damage: Any signs of damage or cracking requires an immediate replacement.
  • Thinning Fin: If the fin or edge opposite the cutting edge of the lawn mower blade is thinning, it is time for a new one.
  • Bending: Bent, warped, or otherwise misshapen blades should be replaced.
  • Dents or Erosion: Dents or erosion on the cutting edge of the lawn mower blade require replacement.

Which way do lawn mower blades go on?

Whether you have a high lift lawn mower, riding mower, tractor, or mulching blades, the simplest way to make sure your new lawn mower blade goes on correctly is to take note of the way the old blades were facing before you remove them.

If you have already removed the old mower blade, inspect the new blades for a "This Side Down" or "Toward Grass" marking. Make sure the grass side of the blade is facing you as you install it.

Most lawnmower brands, including John Deere, Husqvarna, Craftsman, Gator, and MTD, also include blade installation instructions in the owners manual.

How are lawn mower blades replaced?

Before beginning to replace your lawn mower blades or mulching blades:

  • Purchase the appropriate replacement blade for your mower - putting a straight-blade on a mulching mower or vice versa could impact mower performance.
  • Always unplug the spark plug for safety purposes.
  • Access the blades by tipping the mower on its side, keeping the air filter side pointing up to avoid gas or oil leaks.

To replace the blade:

  • Wedge a piece of wood between the mower deck and the lawn mower blade to prevent it from moving.
  • Loosen the mounting nut or bolt in the center.
  • Remove the bolt by turning it counterclockwise until the blade can be removed.
  • Install the new blade, making sure it is facing the right direction.
  • Wedge a piece of wood between the mower deck and the new lawn mower blade to prevent it from moving.
  • Tighten the center mounting bolt completely to secure the mower blades.