Things You'll Need
Valve core removal tool
Tire irons (or other prying tools)
Commonly found on small yard maintenance tractors, tires containing inner tubes have many benefits over their tubeless counterparts. For one thing, if the bead (the seam between the tire and wheel rim) is broken on a tubeless tire, all the air rushes out at once. However, a tire with a tube will usually be unaffected by a small bead seam leak. Tubeless tires that will not hold air can easily be converted into tubed tires; sometimes inner tubes wear out or develop punctures and must be replaced. In either instance, new tube installation is easy to accomplish using basic tools in just a few steps. Installing an inner tube is the same process for tubed and tubeless tires.
Remove the wheel from the tractor, following the manufacturer's suggested technique. If it's not already flat, release as much air as possible from the tire by removing the valve stem core. This is the spring-loaded device within the air valve that keeps air from escaping the tire after it is inflated. Use a valve core removal tool, and twist it counterclockwise to remove the core.
Hammer the sidewall of the tire with a rubber mallet to break the bead loose from the rim on both sides of the tire. Be careful not to hit the rim. Only one side of the bead must be loosened for this process, although loosening both sides makes the process much easier to accomplish.
Pry the tire bead over the rim with a pair of tire irons, flat-blade screwdriver, crowbar or other similarly shaped device. Pry small portions of the tire over the rim in a step-by-step progression. Maneuver a small section of tire over the outside of the rim, then use another prying device to maneuver a section of tire over the rim about 2 inches away from the first section. Continue in this fashion using multiple tire irons (or other flat devices) until the tire has been pried outside the rim around the whole circumference of the wheel on one side.
Once the front side of the tire is off the rim, use a rubber mallet to hammer the protruding air valve (rubber component that contains the valve stem) completely into the tire. Extract the old tube and valve using a pair of pliers.
Examine the inside of the tire for possible causes of the previous tube's failure. Locate and remove any sharp objects and insert the new inner tube into the tire in the opposite way the old tube came out. Add a small amount of air to the tube first to eliminate the "folds" in the inner tube from becoming pinched when the inner tube inflates. Align the air valve so it sticks through the hole in the rim.
Stretch the tire bead back over the rim with the prying tools and mallet. Carefully monitor the position of the air valve to ensure it does not slip into the tire, or become crooked during installation.
Slowly inflate the tire to allow the tube to evenly disperse itself throughout the inside of the tire. Inflate the tire to working pressure to complete the job.
A crooked air valve will rub against the rim until it develops a leak. If the air valve is not completely straight, deflated the tube, carefully maneuver the inner tube to straighten out the valve, then re-inflate.