Riding lawn mowers are convenient, especially for larger areas of grass, but after a few years of regular use, the blades will eventually become dull and chipped. If after mowing your lawn it looks a bit bedraggled, it is likely time to replace the lawn mower blades. Replacing the blade on a riding lawn mower is an easy task that requires just a few, simple tools. How riding mower blades are replaced is fairly universal; however, it is always best to consult an owner’s manual for any particularities.
Pull the riding lawn mower onto a hard surface.
Loosen the negative battery terminal, using a wrench, to remove the battery cables from the positive battery connector. Then disconnect the positive cable terminal. Disconnecting the power source is a safety precaution.
Place blocks of wood opposite each other to support the blade deck if your mower's deck does not have wheels. Some mowers have a deck lever. If so, pull the leaver to lower the deck.
Remove the pins from the front of the blade deck and from the rear of the blade deck, using pliers.
Push in on the belt wheel with a wrench to relieve the tension on the blade belt and remove the belt. Raise the belt deck, if your mower has a lever.
Pull the blade deck out from under the mower and turn it upside down to reveal the blade.
Wedge a piece of wood between the blade and the wall of the blade deck to keep it from spinning. Unbolt the blade, using a socket wrench.
Sweep any loose debris from the blade deck, using a hand broom. Scrape any caked-on gunk from inside the blade deck, using a putty knife.
Spray the bolt with all-purpose lubricant and bolt the new blade to the inside of the blade deck, using the socket wrench. The new blade goes in with the sharp edges facing down.
Slide the deck back under the mower. Reaffix the belt (replace the belt with a new belt if it is damaged or worn), push the deck pins back in place and reconnect the battery terminals, positive first.