How are tires repaired

How to Repair a Flat Tire with a Safe, Permanent Fix

So, you have a flat tire or one that’s leaking air. It’s not the end of the world. Luckily there are safe and cost-effective ways to properly repair most tire punctures. The purpose of this article is to show you the difference between a safe, permanent repair and a temporary string, plug or patch repair.

According to the National Highway Traffic Safety Administration (NHSTA) and the Tire Industry Association (TIA), the only method to properly repair a tire puncture is to fill the injury with a repair stem and back the stem with a repair patch. This is commonly known as a combination repair or a patch/plug repair.

Patch/plug repairs are most often performed using a one-piece repair unit that combines the repair stem and cap (or patch) into one unit. However, special circumstances may require the use of a two-piece combination repair (ex. If the angle of the puncture exceeds 35 degrees). The repair is then permanently bonded to the inside of tire and through the injury channel using a cold, chemical vulcanizing process. The repair essentially becomes part of the tire, creating an air-tight seal that keeps air in and moisture and contaminants out (more on this procedure below).

Tire Plugs and String Repairs are Temporary Repairs

Emergency roadside plug repairs are NOT intended to be a permanent tire repair. Plugs and string repairs are designed to get you back up and rolling long enough to get home or to the nearest service center to perform a proper tire repair.

The common misconception with plug and string repairs is that because they hold air, they are safe to use. While it is true that many plug repairs do a great job of keeping air in the tire, that’s only part of the equation. Because they’re not completely sealing the injury, plug repairs may allow air and moisture to penetrate the body of the tire. Over time, this could lead to a dangerous (or even deadly) blowout.

A Patch-Only Tire Repair Leaves Your Tire Susceptible to Damage

A tire repair that uses only a patch is also NOT considered proper or safe. A properly installed patch will do a great job of allowing the tire to hold air. However, similarly to the plug-only repair, the patch does not fill the injury channel. Therefore, air and moisture could seep into the tire from the tread surface and eventually damage the tire.

The Proper Tire Repair Process According to Industry Guidelines

Only a proper patch/plug repair completely seals the puncture from inside the tire and through the entire injury channel. There are a few extra steps necessary to perform a proper tire repair in accordance with industry guidelines. We’ve developed a simple acronym to help organize and remember the steps: R.E.P.A.I.R.

  • Remove: To begin, the tire must be removed from the wheel assembly. This allows for a thorough inspection of both the inside and outside of the tire.
  • Evaluate: With the tire removed from the rim, the puncture can be thoroughly evaluated to determine the size and angle of the injury. It can also be determined if the puncture did any significant damage to the cords or belts.
  • Prepare: Once the tire has been determined to be in good enough condition to repair, it is time to prep the rubber surfaces to remove any damage and contamination to allow for maximum repair unit adhesion. First, the injury is drilled out using a carbide cutter to strip away and damaged cords or belts. Next, the inner liner is cleaned and buffed to a slightly rough texture. This also helps maximize adhesion of the patch/plug repair.
  • Apply: The next step is to apply vulcanizing fluid through the injury and to the buffed area of the inner liner. It is then allowed to air dry for 5-10 minutes.
  • Install: The one- or two-piece repair is installed through the injury channel and the patch portion is thoroughly stitched to the inner liner using a tire stitcher to completely push out any air that may have gotten trapped under the repair. The over-buffed area of the inner liner is treated with a thin layer of rubber sealant, and the excess repair is trimmed to approximately ¼” above the tread surface.
  • Return to Service: The tire is now ready to be remounted to the rim, inflated, balanced and mounted back on the vehicle.

When is it Safe to Repair Your Tire?

There are a number of factors that may determine whether or not your tire is safe to repair. These factors fall into three main categories:

  • Placement of the Injury: For passenger tires, puncture repairs must be within the crown area of the tire. Damage to the shoulder or sidewall cannot be repaired.
  • Size of the Puncture: For fabric-ply passenger and light truck tires, the maximum repairable injury size is ¼” (6mm). For steel belted light truck, medium and heavy-duty truck tires, the maximum injury size is 3/8” (10mm).
  • Overall Condition of the Tire: The condition of your tire may determine whether it is safe to repair. Excessive wear, casing separation, impact damage and other conditions may make it unsafe to properly repair your tire. For a more comprehensive list of repairable vs. non-repairable conditions visit our blog Can Your Tire Be Repaired?


The occasional flat or leaky tire is an unavoidable part of life. But, taking shortcuts to repair it can be dangerous to you and your passengers. Take the time and do the research to do the job right and/or find a reputable tire repair shop trained in proper tire repair procedure.

When Can a Tire Be Repaired?

From potholes to stray nails and screws, your tires can encounter a lot of hazards on the road. And when they become damaged or go flat, you might be wondering whether you should purchase a new set or get the tire repaired professionally. 

Not every flat or punctured tire can be fixed, but there are other instances where you can get the tire — and your entire car — back on the road with a quick repair. Read on to learn what kind of tire damage can be repaired and when you should get a replacement. 

What Kind of Tire Damage Can Be Repaired?

Can You Repair a Punctured Car Tire?

Puncture location and severity of damage can often be the deciding factors between getting a tire repaired vs. replaced. If you've got a tire that's been punctured in the tread area and it doesn't measure more than 1/4 of an inch (6mm) in diameter, a simple repair may do the trick. 

If the tire has two punctures, getting a tire repaired may still be an option as long as the punctures are at least 16 inches apart and the maximum number of repairs does not exceed a total of 2 in the tire. Any more punctures than that, and you should consider getting a new tire. Punctured tires will likely need to be replaced if:

  • The puncture is more than a ¼ inch in diameter
  • There's a puncture in the sidewall or shoulder of the tire
  • You have multiple punctures that are less than 16 inches apart

Can You Repair a Run Flat Tire?

Durable run-flats, such as Bridgestone DriveGuard tires, can often buy you a little more time in a flat tire situation. But if driven on with less than 15PSI, they may not be repairable. To prevent this issue on run flats and otherwise, avoid driving your vehicle if you have a flat or are low on air.

 Can Tires with Side Bubbles Be Repaired?

If you notice a bubble in your tire's sidewall, this has likely been incurred by high-impact damage. Factors like driving on a flat, hitting a pothole or curb the wrong way, riding over speed bumps or railroad crossings too quickly, or overloading your tires can all lead to this issue. Although this tiny bulge may not seem intimidating, tires with side bubbles are not repairable, and you should have the tire replaced as soon as possible. 

Can You Repair Tires That Have Existing Repairs? 

Repaired tires can often be mended again if the damage doesn't compromise a previously repaired area. For example, if you have a nail-in-tire situation, you may be able to do a quick repair if the puncture location doesn't overlap with a previous tire injury and the repair was done properly. If it does overlap, you will likely need a replacement. 

Can You Repair a Tire After a Car Accident? 

Oftentimes, affected tires will need to be replaced following a major incident. If the tire has sustained serious damage in a crash, such as significant cuts or tread separation, it should be replaced, not repaired. 


Tempting Tire Repair No-Nos 

You might be tempted to do a quick fix when you do have a flat or damaged tire. Here are two that can be used in emergency or short-term situations but shouldn't be considered long-term tire repairs:

Should You Use Sealants or Emergency Inflators?

These fast fixes are a double-edged sword. They'll help you get your car to a local Firestone Complete Auto Care, but don't count on them to keep you on the road for very long. Tire sealants can freeze in cold weather, damage your tire pressure monitoring system, and prove ineffective at repairing any tire damage that's more serious than a slow leak or small hole. It's also important to note that our technicians will not be able to fix punctures in tires with emergency temporary sealants. 

When Can You Patch Up a Flat Tire?

Again, these are quick fixes that aren't meant to enable long-term use of a punctured or damaged tire. When considering a flat tire patch or replacement, remember that a patch doesn't fill in the hole left by a puncture — while a plug doesn't offer a permanent seal. In short, patching or plugging alone are never adequate long-term solutions. That's why at Firestone, our technicians can use a patch-plug combo to provide an adequate long-term solution for some tire punctures. 


Taking Care of Your Tires

To ensure your tire is safely repaired or replaced, it's best to have it inspected and serviced by a trained technician. Visit your local Firestone Complete Auto Care and ask about our tire repair services. Your safety is our priority, and we back all of our work with a triple promise that guarantees your repair will be Fixed Right, Priced Right, Right on time.  

Now that you know when to repair vs. replace a car tire, schedule your appointment today!

what tire damage can be repaired :: Autonews

Photo: Mikhail Tereshchenko / TASS

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Nail, rebar or sharp stone - sometimes you can damage a tire almost from scratch. First of all, the scale of damage is important, and often rubber can still be repaired. Most often, motorists turn to tire shops for repairs in the middle of autumn or spring - just in the season of replacing summer tires with winter tires and vice versa. In order not to stand in lines, it is worth knowing exactly when to go to the tire shop and when to go to the store.

The most common "injury" to rubber is a puncture, and it can most often be repaired. Professionals in the nearest service will do it much faster, and your hands will remain clean. But if the puncture caught you in a deserted place, and there is a pump and a tire repair kit with harnesses in the trunk, you can patch up the tire yourself. Most often, when repairing the front tires, the wheel can not even be removed, it is enough to turn the steering wheel in the right direction and find the puncture site.

First, the hole is cleaned with a helical awl, the repair harness is smeared with glue and tucked into the eye of the awl, after which it is inserted into the tire hole. With a sharp movement, the tool is removed, and the tourniquet remains inside and securely clogs the hole. The tails are cut with a knife, but it is recommended to leave about 20 mm. After that, the tire can be inflated and the pressure checked.

Repair with tourniquets is not considered long-term, because after some time they dry out and begin to let air through. A more advanced puncture repair method is vulcanization. The hole is sealed with an elastic patch, and the funnel at the puncture site is filled with a special compound. A vulcanizer is put on top, which heats the patch and solders the excess.

Under service conditions, the puncture is also repaired with cord fungus. The puncture site is processed and drilled to roughen. Everything is smeared with glue, after which a fungus is introduced from the inside of the tire, its cap is rolled, and the excess legs are cut off from the outside.

Photo: PA Images / TASS

A puncture can also be repaired with sealant. Many car manufacturers with run flat tubeless tires put compressor repair kits in the car instead of a spare tire - a bottle of pressurized sealant. The car is raised on a jack, after which the sealant is pumped into the damaged wheel through the nipple. Next, you need to spin the wheel and pump it up. After repair, the car should be driven a couple of hundred meters to check the tightness of the tire. If it has not recovered, the procedure is repeated.

It happens that a self-tapping screw or a nail closes the hole in the tire, remaining inside. Do not rush to pull it out - until the pressure drops, you can safely get to the service for vulcanization. Sometimes the wheel begins to blow off a few weeks after the self-tapping screw got into it. Therefore, it is better to check tire pressure periodically, and if the pressure sensor lights up, you should at least visually inspect the tire for a nail head.

A bump or bulge most often occurs on the side of a tire after hitting an obstacle or hitting a hole at speed. From the impact, the sidewall carcass threads are damaged, the tire ceases to hold the load and pressure, swelling appears. Any small bump eventually turns into a larger one, and with such a defect, the wheel can burst at any time. This is a direct safety hazard because a sudden flat tire can cause loss of control and a road accident.

Some bulges can be repaired, but no patch will ever restore a tire to factory stiffness. The ideal option in this case is to replace the tire. If a hernia has appeared on the tread, then you can extend the life of the tire with the help of cord patches - ready-to-use patches with an adhesive layer. But if swelling is found on the sidewall, the likelihood of repair is minimal, the wheel is easier to change. Blisters on low profile tires are generally not repairable.

Only car service professionals can repair a side cut. Cord patches will be needed to repair the damage, but after some time the wheel will still have to be changed. This method will work only if the gap is not in the shoulder area of ​​the tire, then no one will repair it.

In general, cuts or punctures, unlike punctures, are considered non-repairable, since the integrity of the frame is violated. And breakdowns do occur on the go, when the tire abruptly loses pressure and has time to make only a few turns “on the rims” before it comes to a complete stop. In this situation, the cord breaks and the layers of the tire are destroyed. Even if it is possible to close the hole, it is not recommended to use such a weakened tire.

Photo: Mikhail Pletsky / Russian Look

Cracks, sidewall abrasions and unprofessional tire fitting can also lead to tire problems. Cracks can occur as a result of improper storage of tires. Their danger is that moisture begins to flow to the cord, and this already renders the frame unusable. Air can also escape through cracks. Cracks cannot be repaired and tires will not last long. A tire with cracks is deformed, blistered, and may even break while driving.

Rubbing against curbs or driving on uneven roadsides can damage the tire sidewall. When driving like this, it is worth inspecting the tires for damage regularly. If a slight wear is found, the wheels can be swapped, which will slightly extend their service life and allow you to delay the purchase of new ones.

Improper fitting can damage the tire bead. In this case, the tire will lose its geometry and sit on a disc with a bevel, “eights” will be visible during rotation, and the driver will feel vibration while driving. It is impossible to repair this defect, the wheel must be changed as soon as possible, otherwise there is a risk of damage to the suspension.

How to Tires

How tires are repaired

In this section we will show you the most popular types of tire repair.

1. Tire repair with HARNESS.


The harness can be installed even without removing the wheels from the car. This is a cost-effective tire repair option that does not take time and does not require wheel balancing. Minimum operations on the wheel, respectively, low cost of work.


The tourniquet is still a makeshift. Indispensable on the track in the distance from professional tire fitting. The warranty does not apply to the harness, although we will be honest, many motorists roll back on a wheel repaired in this way for more than one season without any problems.


Any operation with car wheels should be entrusted to professionals who have the necessary set of modern repair tools. Trust us with your safety.

2. Radial patch.

Radial patch is indispensable for the repair of through-hole punctures in the tread of a tire with a slight damage to the cord. The patch is made of durable flexible rubber. The adhesive layer has excellent adhesion, which in combination with a special adhesive gives excellent results! A wide range of tire repair patches will save almost any tire.
No defects found! Our tire service in VAO will perform high-quality repairs of any complexity!

3. Patch "MUSHROOM".

Perhaps the best option for repairing a puncture tire. The leg of the fungus reliably clogs the through hole, and the cap enhances protection by fitting snugly on the inside of the tire. The only drawback, if we talk about it at all, is the inability to close a puncture going diagonally. Like Radial Patches, Fungus Patch works in combination with quality adhesives and sealants. Shishomontazh in VAO has a full set of tools for repairing wheels with the "GRIBOK" patch. trust us with your tires.

4. Radial cord patch.

Repair of tires with severe cord damage, repair of side cuts, repair of cuts in combination with hot vulcanization. The cord patch is made using a thread that is elastic in tension, which makes it possible to reliably strengthen the damaged surface of the wheel. Of the shortcomings - heavy weight, requiring partial balancing. Tire fitting in VAO will carry out any complex repair of your tires!

General. The service center - "VAO tire fitting" provides a full range of services related to the repair of tires and wheels. Tire fitting in VAO is equipped with modern European-made equipment. The presence of a 3rd hand at the tire changer will help solve the problem of removing and installing low profile and run flat tires. VAO tire fitting will repair side cuts, repair punctures.

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