How to fix a flat tyre - in simple steps with video

How to fix a flat tyre - in simple steps with video
Stranded at the side of the road with a flat tyre and no spare wheel? Don’t panic: it can most likely be repaired.

If you have a flat tyre we will help you get moving again as quickly as possible with our simple video instructions on how to repair a tyre:

It's important to note you should never try and change a tyre if your personal safety is at risk. If you aren't confident enough to try to repair the tyre yourself and need assistance, you can call the RAC:

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How to repair a flat tyre in five steps

Find a safe place to park. It’s better to drive further and risk damaging the wheel rim than stop somewhere dangerous – such as on a narrow road.

Leave your hazard lights on when you park. Put on your reflective jacket if you have one, and position your warning triangle to alert oncoming drivers.

Using a tyre repair kit is very straightforward. Here’s our five-step guide:

1. Prepare the car

Apply the handbrake and remove all passengers from the car. Take the can of sealant and compressor out of the boot.

2. Locate the puncture

Examine the tyre carefully to find the puncture, if you have a rip in the tyre sidewall, a hole over 4mm in the tread or the wheel itself is damaged your repair kit is unlikely to work and the tyre will need to be changed.

If you do have a spare, you can find out how to change your tyre here.

If you spot a nail or piece of glass in the tyre, leave it there; removing it may simply make the hole bigger.

3. Connect the repair kit

Most repair kits will require you to manually squeeze all of the sealant into the tyre, via its adapter. You may have to remove the tyre valve to do so, but instructions in either your repair kit or vehicle handbook will tell you how to do this.

Once all of the sealant is in the tyre, attach the compressor to the tyre valve. Then plug the compressor into the cigarette lighter or 12v socket inside your car.

You may have to roll the car forward slightly to ensure the sealant spreads through the entire tyre.

Some sealant kits, however, will have an additional adapter, allowing you to fit the bottle of sealant into the compressor, so you can pump the sealant into the tyre with the help of the compressor.

4. Pump up the tyre

Check the car is in neutral, then start the engine and switch on the compressor.

Inflate the tyre to the correct PSI/Bar recommended in your vehicle handbook.

5. Replace the tyre

Once the tyre is inflated to the recommended pressure, drive to the nearest garage or tyre fitters.

Do not exceed the maximum speed detailed in the car’s handbook (and usually also on the repair kit itself).

How long will a repaired tyre last?

A repair like this is only a temporary measure and you should replace the damaged tyre – and the can of sealant in the repair kit – as soon as possible.

Driving on a repaired tyre for longer than necessary could put you in danger, and in trouble with the police.

According to a recent Which? survey, more than half of new cars come with a tyre repair kit rather than a spare wheel.

The reasons for this include weight, fuel consumption, space and cost, but the upshot is that you’re less likely to get back on the road after a blowout.

That’s because repair kits – which use foam sealant to temporarily plug a hole – aren’t suitable for all types of punctures.

If you have a rip in the tyre sidewall, a hole over 4mm in the tread or the wheel itself is damaged, the kit is unlikely to work.

My car doesn’t have a spare tyre or puncture repair kit

If you don’t have either of the above, help is at hand. Find a safe place to stop, then call the RAC on 03301 598 751.

If your MOT is due or if you would like to book your vehicle in for a full car service, you can book online with your local RAC Approved Garage today, or why not use an RAC Mobile Mechanic.

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How to fix a flat tyre - tips

  • Can you drive on a flat tyre?

    In short, no.

    Driving on a flat tyre will lessen your control of the vehicle, cause damage to it and see you hit with three penalty points and a £100 fine for driving a defective car.

    The Highway Code states tyres should be inflated to the manufacturer’s specification and if you have a flat tyre you should pull over as soon as it’s safe to do so, to avoid putting yourself and others at risk.

  • What is a run-flat tyre?

    Run-flat tyres have specially reinforced sides which enable you to continue to drive on a puncture, provided you drive at limited speeds and for a limited distance – usually 50 miles maximum.

    While you’ll be able to continue driving for a limited amount of time on run-flat tyres they can’t be repaired as easily as regular ones, so you’ll eventually need to buy a new tyre should you experience a puncture.

  • What happens when you drive on a flat tyre?

    The first thing that’ll happen is a loss of control over your vehicle, which could put yourself and others at risk. That’s why you should slow down and pull over as soon as it’s safe to do so.

    Driving on a flat tyre for long enough could also cause damage to important components of your vehicle – including brake lines, suspension and wheels – which could see you hit with a hefty repair bill.

  • How do I prevent my car from getting flat tyres?

    To help avoid flat tyres, keep a careful eye on your vehicle, checking tyre inflation levels, tyre tread levels and brake pads, as these can all be factors.

    You should also avoid driving on roads where you’re more susceptible to picking up a flat tyre. Roads such as those around construction sites where there may be debris like nails and glass shards on the road surfaces, on dirt tracks where there may be hidden rocks jutting out of the ground, or on particularly pothole-ridden roads.

    Read our guide on how to report a pothole and claim for damage here.

  • How can you tell if you have a flat tyre?

    If you’re driving and you pick up a flat, the first thing you’ll likely notice is your steering feeling funny for no reason or your car slowing down – both of these should be signs you need to pull over and check your tyres.

    A full blow-out will mean you hear a thud and a flapping noise alongside any issues with your steering. Pull over as soon as it’s safe to do so and check around your vehicle.

  • How many miles can I drive on a flat tyre?

    As soon as you think you’ve got a flat tyre you should pull over as soon as it’s safe to do so and check your vehicle for signs of a puncture.

    Technically, you may be able continue a little further than this but, not only would this cause significant damage to your vehicle, it puts yourself and other road users at risk as you do not have sufficient control of your vehicle.

  • Is it safe to inflate a flat tyre?

    Yes, simply follow our video guide above on how to inflate a flat tyre – just remember that you’ll still need to visit a mechanic so that they can replace the damaged tyre.

    If your tyre fails to inflate when you’re inflating it, it could be too damaged. If this is the case, use your spare tyre or call RAC breakdown assistance and one of our patrols can help you out.

  • Can I drive on a flat tyre to get air?

    You shouldn’t drive on a flat tyre at all as this can put yourself and other road users at risk and cause permanent damage to your vehicle.

    If your tyre has a slow leak and you have means to inflate it (such as sealant and a compressor) then you should be able to inflate your tyre enough to safely transport you to your nearest garage.

    Find out where your nearest RAC Approved Garage is.

  • Why do I have a flat tyre?

    There are a number of reasons why you could have a flat tyre, from worn-out or over-pumped tyres to vandalism. The most likely reason for a flat tyre is a puncture after driving over a sharp object, such as shards of glass or a nail.

  • Why do I keep getting flat tyres on my car?

    If you keep getting flat tyres it could be a sign of an underlying problem with your car, such as a faulty valve stem or a damaged mounting surface of your wheel.

    Flat tyres could also be caused by your driving habits, for example driving in areas where there is lots of debris on the road (such as near construction sites) or in off-road locations (if your car is not equipped for off-road driving).

  • Should all tyres have the same pressure?

    Not necessarily. Tyres should always be set to the pressures recommended in your owner’s manual, and these may not be all set at the same pressure.

    For example, some front-wheel-drive vehicles have higher pressures in their front tyres to ensure better weight and braking bias.

  • Is it bad to have uneven tyre pressure?

    Uneven tyre pressure can lead to uneven traction on the road and uneven tyre wear and tear. This can cause problems with stability which could lead to problems on the road.

    Remember that only tyres on the same axle need to have the same tyre pressure, so you may well find your rear tyres have a different recommended tyre pressure from your front tyres.

  • Should I fill my tyres to max pressure?

    Almost always, no. When it comes to tyre pressure, the maximum is often not the optimum.

    Your vehicle will have a recommended pressure range, either in bar or pounds per square inch (PSI). Check your vehicle handbook or the stickers on your bodywork and make sure you use the right pressure for your car.

  • What happens if there's too much air in my tyres?

    Putting too much air into your tyres can be just as bad as not putting enough air into your tyres, as it can cause them to wear unevenly and can even lead to blow-outs if they get too hot.

    Ensure you don’t over-inflate your tyres by filling them up to within your vehicle’s recommended pressure range, which should be available in your owner’s manual or on a sticker on your car’s bodywork.

  • At what PSI will a tyre explode?

    There’s no set PSI at which a tyre will definitely explode but generally anything between 150 PSI and 200 PSI could see your tyre blow. Make sure your tyre pressure remains at the safe, recommended level at all times.

  • How often should I put air in my tyres?

    Tyre pressure should be checked every week, with air pumped in if the pressure has fallen outside of the recommended range to help keep you safe.

    You should always check your tyre pressure when the tyres are cold — i.e. before you’ve made any journeys that day. This usually means after the vehicle has been parked for three hours or driven less than a mile. This is because warm or hot tyres that have recently been driven on may give inaccurate pressure readings.

  • Will a flat tyre ruin my wheel?

    That largely depends on you. If you pull over as soon as it’s safe to do so when you think you may have a flat tyre, you should be able to limit any lasting damage to your wheel.

    However, if you dangerously decide to continue driving you could do lasting damage to your wheel and your vehicle, as well as putting yourselves and other road users at risk.

  • How much does it cost to fix a flat tyre?

    That depends on where the puncture is. If it’s located in the central part of your tyre it may be possible for a mechanic to carry out a safe and lasting minor repair which will obviously be less expensive.

    However, if your tyre is punctured on the side it may not be possible for a quick repair to provide a lasting, safe repair which means you may need to pay out for a new tyre.

    Find out where your nearest RAC Approved Garage is.

  • Can slow punctures be repaired on run flat tyres?

    The short answer to this question is yes, slow punctures on run flat tyres can be repaired. However, it is important to note that the process is slightly different than repairing regular tyres.

    Run flat tyres are designed to allow you to continue driving even when there is a loss of air pressure due to a puncture or leak. This is because the sidewalls of the tyre are reinforced to provide extra support and stability. This makes them ideal for emergency situations when you need to move your vehicle to a safe place.

    Due to the reinforced sidewalls of run flat tyres, regular puncture repairs cannot be performed. Instead, the tyres must be removed and inspected for any further damage. If the slow puncture is determined to be caused by a nail or other external object, the tyre can be patched from the inside.

    It is important to note that once a run flat tyre has been punctured, it can no longer be used as a run flat. The reinforced sidewalls will be weakened and the tyre cannot be used safely in an emergency situation. Therefore, it is important to have the tyre replaced as soon as possible.