Before you attempt to replace the tires on your Craftsman lawn tractor, check your warranty. For a period of time, a limited warranty may cover the replacement of tires worn through regular use. Punctures in the tire, however are unlikely to be covered. And the best way to repair this type of damage is to replace the tire. Patches may be a temporary fix, but they may leak and cause the mower to mow unevenly.
Park the lawn tractor on a flat, concrete surface. Disengage the mower's engine and engage the parking break.
Place a jack near the tire that you intend to remove (make sure that the jack is in secure contact with the bottom of the frame of the lawn tractor). Then lift the lawn tractor so that the tire is not touching the ground.
Remove the axle cover (if it is stubborn, you may want to use a pair of pliers), the retaining ring and both washers. On rear tires, you will then need to align the grooves in the rear wheel hub and axle and then insert the square key before removing the tire.
Remove the rim and tire from the axle.
Release the air from the tire. Press down on the air valve until all the air escapes.
Pull the tire off of the rim. To make your job easier, first loosen the portion of the tire in contact with the lip of the rim on both sides with a flat head screwdriver to break the seal. If the tire is still too tough to pry off, place tire lube between the rim and the tire and try pulling it off again.
Put the new tire on the rim. Again, this process will be easier if you lube the portion of the tire that will be in contact with the rim with tire lube. Then, place the tire over the rim at a 45 degree angle. Push the lower part of the tire over the lip of the rim (with the help of a flat head screwdriver wedged between the tire and the lip of the rim if necessary). Move around the tire, pushing it down section by section until it is on the rim.
Replace the tire and rim on the axle. Remove the square key on a rear tire, place both washers on the axle, then the retaining ring and then screw the axle cover on tightly.
Place a ratchet strap around the new tire and tighten it securely so that the inside of the tire is set firmly against the rim's lip on both sides.
Lower the mower until the tire touches the ground.
Fill the tire with air using an air compressor until the tire reads 7 psi (5 psi for rear tires).
Remove the ratchet strap.
Fill front tires to 14 psi and rear tires to 10 psi.
Lower the Craftsman lawn tractor and remove the jack.