This article will cover the procedure when replacing the blade of a petrol lawnmower.

Tools and parts needed: 

  • Thick Gloves
  • Socket wrench
  • A new washer

To remove your blade, please try the following:

  1. Take spark plug cap off.
  2. Make sure you have good, thick gloves.
  3. Lift your mower at an angle by pushing back down the handles (have someone assist you with this), or, drain the machine of its fuel and oil and turn it upside down.
  4. Grip the blade in one hand, and in the other place the socket wrench on the end of the blade-bolt.
  5. Unscrew the bolt, rotating anti-clockwise.
  6. Take blade off the adapter/boss/carrier.
  7. Affix your replacement blade onto the adapter, being careful to fit the location pins correctly.
  8. Use a new washer, throw away the old one.
  9. Insert and tighten the blade bolt clockwise with the wrench.

Note I: If the blade adapter is damaged, then it also needs replacing.

Note II: If your blade bolt is not loosening, you may need to clamp the blade, or wedge a block in the gap to keep it in place.