How to Fix a Flat Tire
A flat tire is one of the most common mechanical issues drivers will face, so knowing how to deal with tire problems is a key skill for drivers.
Improperly handling a flat tire can result in expensive tire damage or even cause an accident.
This article covers the ins and outs of dealing with flats so you can be prepared and safe.
8 steps to fix flat tires
Most vehicles are equipped with a spare tire, so one way to deal with a flat is to take it off the vehicle and put on the spare. But spares have their limitations: many are undersized and only designed for very short ranges. Additionally, a spare won’t help you if you get a second flat before you can repair the first one. Your spare also might not be properly inflated or kept in good condition. These are all reasons why it is helpful to know how to fix a flat, in addition to knowing how to change a tire.
Here are eight steps for fixing flats.
1 - Take off the wheelYour operator’s manual should have detailed instructions on how to do this step and where to find the necessary tools (a jack and a lug wrench, which are standard equipment in all vehicles). But to give a condensed version, you first use the lug wrench to slightly loosen the nuts holding the wheel onto the vehicle. You then raise the car with a jack, finish removing the nuts, and pull the tire off the vehicle.
2 - Locate the puncture
First check the entire circumference of the tread for sharp objects that remained embedded in the tire. Common culprits are nails, screws, or broken glass. If there is still some air left in the tire, you can also listen for the sound of air escaping and use it to guide you to the puncture site. Alternatively, cover the tire in soapy water and look for tell-tale bubbling. A puncture caused by an object that entered and exited the tire can be more complicated to find; once you do, be sure to mark it with chalk or other identifier so you don’t lose track of it.
3 - Assess the puncture
Not all punctures can be fixed using a repair kit, and some can’t be fixed at all, so it’s important to identify whether the puncture you find is repairable. Damage or a leak in the sidewall is uncommon, but it cannot be safely fixed with a plug. Other extensive damage, such as a blowout or dented rims, requires replacing the tire rather than attempting a DIY repair.
4 - Remove the problem
If the puncture was caused by an object that remained embedded in the tire, take it out. You may need to use pliers to pull it out, or, in the case of screws or bolts, you might be able to remove it by turning it counter-clockwise.
5 - Widen the hole
Your tire repair kit will have a reamer, which is a tool shaped like a T or screwdriver and designed to enlarge holes. If the puncture has a diameter smaller than that of a pen, you’ll need to use the reamer to widen the hole so you can then insert the plug. Push the tip of the reamer (the bottom point of the T) into the hole and begin rotating it. Continue reaming until the tool can freely slide in and out of the hole.
6 - Put in the plug
Most plugs look like a segment of rope, which you thread through the fork-like tool in your kit. This tool is a rod with a metal loop at the end that is not quite fully enclosed and looks like the eye of an oversized needle.
Pull the plug through until there are equal lengths on either side. Then apply the glue or rubber cement that comes with the kit to the surface of the plug.
Press the plug firmly into the puncture until only the two tips are visible above the surface of the tread.
Remove the insertion tool by pulling it upward swiftly and firmly; then pare down the tips of the plug until they are flush with the tread.
7 - Air up your tire
Now that your plug is in place, you’ll need to air up your tire (using a portable compressor or pump). Check the seal of your plug to make sure no air is escaping.
8 - Put the wheel back on
Mount the tire on the bolts, put the lug nuts in place, and tighten them somewhat in a cross pattern. Let the vehicle down off the jack and finish applying torque with the lug wrench in the same cross pattern. Once you store your tools, you’re ready to continue on your way. It’s best to stop after fifty miles or so and inspect your plug to make sure everything is in order.
Items you'll need to fix a flat tire
Aside from the normal tools needed for removing a tire-wheel unit from a vehicle and putting it back on (lug wrench and jack), you’ll also need a repair kit and a portable compressor (or a large manual pump will work if you’re willing to break a sweat). The repair kit should, at minimum, contain a reamer, an awl-like tool for inserting plugs, plugs, and some sort of glue or binder for sealing the plug. Some kits will also have pliers for pulling out the sharp object that popped the tire in the first place, and a utility knife for cutting the plug flush with the tread once it’s installed. If the kit does not have these items, you should carry them separately.
As their name suggests, airless tires are not filled by inflation, so they aren’t vulnerable to punctures and can tackle more rugged activities. They can also have the potential to contribute to vehicles’ fuel economy by reducing rolling resistance. However, this technology is largely in the development phase and is not yet widely available at prices comparable to pneumatic tires.
An experienced person with the right tools should be able to complete the process in about 15 minutes. But if you are still learning how to fix a flat, it may take around twice as long.
If you have a spare tire, you can jack up the car, remove the flat, and replace it with a spare. If you have the right tools to do so and the puncture is in the tread, not the sidewall, you can also fix the tire by following the steps in this article. If neither of these is an option, call a tow truck. Don’t drive on the flat.
No. A flat tire will compromise your control over your vehicle’s steering, braking, and acceleration. Also, driving on the flat can further damage your tire to the point where it is beyond repair, and it can even cause dangerous damage to the wheel and/or braking and suspension systems.
A professional will most likely charge between $15 and $30 to fix a flat, although of course the exact price will depend on the service provider. If you fix the flat yourself, you’ll need a plug kit, which costs between $10 and $40.
If your tire goes flat while you’re driving, the vehicle will likely pull to one side. You also may feel vibrations and have to step harder on the gas to maintain your speed. A thumping or humming sound could also tip you off to a flat.
If the flat tire is on a vehicle that has been stationary for an extended period of time, the flat might be caused by a slow leak, and airing up the tire might let you to travel a short distance before fixing the problem. Otherwise, airing up a tire without fixing the puncture won’t do you any good.
Driving any distance at all on a flat tire is not recommended. It can damage the tire’s internal structure, leading to a much more expensive repair, and it can also cause potentially dangerous damage to other parts of the vehicle, such as the wheels, braking system, or suspension.
If the rim is touching the ground, there is no air left in the tire and you have a flat. If by just looking at a tire you can’t tell whether it is flat, you can use a tire pressure gauge to check to see if there is any air left in it.
If you have a flat, a damaged tire, or just want further information, contact your nearest tire dealer for expert guidance that will keep you safe on the road.