If a leaking tire was already plugged awhile ago, and now the plug is leaking again, is it possible to repair the plug? Or, is purchasing a new tire the only real option?

 

Get it patched instead. If its near the sidewall replace the tire.

 

+1 ^^

 

+2. unless you're on the side of the road and it's an emergency don't replug at this time.

 

unless your doing some really serious Hot laps or Time Trials or race in a Time Attack Series. Plugs are fine.

 

i don't know if that's true for *multiple* plugs. because aren't you supposed to use a ream to clean the hole before you reapply the plug?

i guess it's best to check with the tire shop too because i'm under the assumption they have to ream the hole each time which makes it bigger and eventually a plug won't fit properly. if i'm incorrect then there's no reason not to use a plug. but the other side of the coin is if you're doing this multiple times you will save money by patching it.

 

From the Bridgestone limited warranty:

Any tire repair done without removing the tire from the wheel is improper. The tire must be demounted from the wheel and the interior inspected for damage that may not be evident on the exterior of the tire.

• Using only a plug/stem, or using only a patch, is not a safe or proper repair. A patch must be applied to the interior of the tire and the puncture hole must be filled with a suitable plug/stem fi ller to prevent inflation pressure loss and contamination of the steel belts and other plies

 

Plugs are okay but I wouldn't recommend plugging a plugged hole. You can try patching at a shop but at this point, I'd start thinking about a new tire.

I have a very nice plug kit and it has gotten me out of a few tough spots... they work well if done correctly the first time.
Never plug a tire near or on the sidewall. Otherwise, they're okay. If yours is leaking, it was either done incorrectly, a lousy plug quality kit was used, the damage was too large for the plug, or it was too close to the sidewall.

Plugs are designed to get you back up and going again but they are not intended to be long term solutions.
I have the Safe Seal kit... has served me well.

 

well put Aeson. i bought a plug kit also that i keep in the trunk although i suppose it would be good if i found an old tire on the road to practice with first lol.