To properly repair a radial tire, the hole or object in the tire must be within 3/4 from the edge of the tread. Most states prohibit sidewall patches. The old-fashioned plugs are now prohibited in many states as well. Due to liability, many reputable places will require a patch plug inserted into the radial tire, which requires breaking the tire down off the rim. The patch plug is much more costly than the old-fashioned push-in-plugs, but they're far more superior, much more reliable and much safer.
Locate the foreign object or hole in the tread of the radial tire. If you need to, inflate it with air up to 30 PSIs (pounds per square inch) and spray the tread to locate the hole or object that is leaking. When the soap and water hits the spot that is breached, it will bubble as the air purges out of it. Mark the hole or object with a tire crayon.
Deflate the tire by removing the valve core with a valve core remover and remove the wheel weights from the rim with a tire hammer.
Break the tire down from the rim, using the tire machine.
Place the tire into the tire stand/tire clamps so that the hole or object in the tire is strategically located to work on easily. If the tire was a clock, the object or hole would be about in the 4 o'clock position on either side of the clamp.
Extract the object with a set of dikes or run the tire repair reamer through the hole until it moves easily.
Squirt a liberal amount of tire pre-buff cleaner on the inside of the tire on the damaged area, and allow it to drip down into the bottom of the tire. Buff the damaged area of the tire using the pneumatic tire buffer.
Apply a light coat of tire vulcanizing liquid to the inside of the damaged area of the tire that was just buffed. Spread it around thinly so that it covers the area just over the size of the plug patch.
Allow the vulcanizing liquid to almost dry. This may take a few minutes, depending on the amount you put on. To optimize your time, you could clean the rim and/or replace the valve stem if desired. The consistency of the vulcanizing fluid should no longer shine and appear dry but still feel tacky.
Choose the right size of patch plug for the job. Using too large of a plug will make it hard to pull through the tread; too small a plug won't plug the hole. Choosing one will apply a degree of common sense and compare the size of the plug to the size of the hole. Peel the protective covers off the top and bottom of the patch plug, but be careful not to touch the bottom of the patch.
Insert the steel patch plug point into the hole from the inside of the tire. Poke the metal plug point through the hole as far as you can by hand. Pull the plug point through the tire from the outside of the tread area, using a pair of channel locks or pliers. The metal plug point will pull away from the patch plug, and you can discard it. Grab the plug with one hand and pull so that the patch in the inside of the tire dimples in the middle. Run the tire repair roller over the patch plug inside the tire to press the patch plug securely to the tire. Run the roller over in several different directions while holding the plug.
Add another liberal coating of vulcanizing fluid to the patch plug inside the tire and allow it to dry.
Replace the tire onto the rim, inflate the tire to recommended specifications, and spray with the water bottle where the plug is protruding from the tread. If there are no bubbles, cut the protruding plug with a set of dikes and balance the tire on the tire balancer.
