Safety First

• Raising the mower off the ground will make this task much easier. Drive the front wheel of a tractor onto a sturdy set of ramps and place wheel chocks under the rear wheels.
  
  Disconnect one terminal of the battery to eliminate any chance of the engine starting when you are underneath the tractor.
  
  Always have an assistant whenever working under a vehicle.
  
  

Expose the Bolt Head

• Lawn tractor blades are mounted with a single bolt through the center of the blade. Often the head of this bolt will be caked with dirt, and a socket wrench will slip off. To remove the bolt without stripping the screw head, this dirt will have to be removed.
  
  A chisel or screwdriver can often be used to pry off this dirt, and spray-on cleaners can help loosen it.
  
  Do not try to remove the bolt head until a socket wrench can securely grip the head, or busted knuckles and a stripped bolt head are likely.
  
  

Wedge the Blade and Remove Bolt

• A length of 2x4 lumber can make a good wedge to hold the blade while you loosen the mounting bolt. Wedge the wood between the blade and the mower shroud, or have an assistant hold the wood to prevent the blade from spinning.
  
  A slot cut into the 2x4 to hold the blade can assist in wedging the the blade in place.
  
  With the blade held tightly in place, use a socket wrench to remove the blade. A breaker bar, or a piece of pipe to extend the socket handle, may provide more leverage to remove stubborn bolts.
  
  Before completely removing the bolt, make note of the locations of washers and the orientation of the blade so you can put it back on correctly.
  
  Use a copper based thread lubricant when reinstalling the blades to make removal easier in the future.