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Fixing a tyre puncture...


Over the course of twelve months of motoring, it’s almost inevitable that one of the tyres on your vehicle will suffer a puncture.  What normally happens is that you drive over a screw, nail or other bit of sharp debris left on the road and it somehow manages to puncture the tyre.  Often it remains buried in the tyre.  The first sign that a tyre has been punctured is that it starts to leak air.  Often what happens is that you notice the tyre is low on air, so you pump it up.  Then, the next day, the tyre looks low on air again.  This is a sure sign that the tyre has got a puncture because the tyre is obviously leaking air.

Another sure sign is if one of your tyres sounds like it’s tap-dancing as you drive along.  When this happened to me, it took me a while to figure out that this was the sound of the head of the bolt stuck in one of the tyres making contact with the road as the wheel rotated.  I initially thought I had some major mechanical problem!


It’s easier to fix a tyre puncture than have to keep inflating the tyre that’s leaking air…

When the offending screw, nail or whatever else remains in the tyre, the tyre tends to leak air slowly.  Nevertheless, it needs to be fixed because the only alternative is to keep pumping it up every day or every second day.  Many of us have experienced this and it’s extremely tedious and frustrating because it’s obvious that it’s not fixing the problem.  Generally we’re all busy and we don’t have time to devote to fixing the puncture.  In any case, most of us can think of other things we’d rather be doing than fixing a punctured tyre! However, it takes less time to jump in and fix the puncture than to suffer the tyre leaking air day-in, day-out.


Finding the cause of the tyre puncture…

The easiest way to find the puncture is to run your hand gently over the entire surface of the tyre (to avoid the possibility of cutting your hand on the thing puncturing the tyre) even while the wheel is still attached to the vehicle.  Generally the screw, nail or whatever else that’s puncturing the tyre isn’t fully embedded in the tyre so you should be able to feel it.  The alternative is to simply look for it.  If you still can’t find the cause of the puncture, move the vehicle so that the section of the tyre that was in contact with the ground can be inspected.

If you still can’t find the cause of the puncture, it’s necessary to remove the wheel from the vehicle and inspect it more carefully.  A last resort is to pump up the tyre that you’ve removed from the vehicle to a reasonable air pressure and submerge the tyre in a large container of water, a section of the tyre at a time, in order to see if any air is leaking out of the tyre into the water and forming bubbles.  This enables you to home in on the location of the puncture.

Having found the cause of the puncture, it’s often possible to fix the puncture without even removing the wheel from the vehicle if you didn’t need to remove the wheel in order to locate the puncture.


Keeping a tyre puncture repair kit in your vehicle ready for when you need it will pay dividends…

You can obtain a tyre puncture repair kit from your local automotive parts shop.  It’s a good idea to keep this kit in the rear of your vehicle, ready for when you’ll inevitably need it.  (For a list of other items that are well worth keeping in the rear of your vehicle, please see the section titled, Getting Organised.)  The tyre puncture repair kit contains the following components:

  • Cylindrical rasping tool for making the hole in the tyre the right diameter for receiving a puncture-repair plug.
  • Tool for inserting the puncture-repair plug into the tyre.
  • Puncture-repair plugs.

Procedure for fixing a tyre puncture...

Once the cause of the puncture has been found, here are the steps for fixing the puncture:

  1. Determine whether the puncture can be fixed with the wheel still attached to the vehicle or whether the wheel must be removed from the vehicle.  It’s often possible to fix the puncture with the wheel still on the vehicle by moving the vehicle forwards or backwards until the puncture in the tyre is in a more accessible position.  If it’s not possible to fix the puncture with the wheel still on the vehicle, remove the wheel from the vehicle.


  2. Inflate the tyre to its normal air pressure using a foot pump and tyre pressure gauge or some other source of air like an air compressor. The tyre will have a low air pressure due to the leak but it needs to have a normal air pressure so that the puncture repair can be completed successfully. So you have to inflate it to its normal air pressure.


  3. After removing the cause of the puncture with needle-nose pliers, bull-nose pliers or multi-grips, immediately insert the rasping tool into the hole in the tyre before much air has a chance to escape from the tyre. You’ll need to do this quickly since the air will come out in a rush after the cause of the puncture is removed.


  4. Move the rasping tool up and down in the hole with a rotating motion at the same time in order to make the hole the right size to receive the puncture-repair plug.  You may need to use a lot of force to do this since the diameter of the hole may be considerably smaller than the diameter of the rasping tool.

    The reason for inflating the tyre to its normal air pressure in step 2. above is that, without doing this, it will be difficult to insert the rasping tool into the tyre because the tyre will simply deform as a result of its low air pressure arising from the leak.  The normal air pressure in the inflated tyre causes the tyre to remain rigid so that the rasping tool can be inserted successfully.

    In effect, the purpose of the rasping tool is to file rubber material away around the inside of the hole.  After having done this, leave the rasping tool in the hole to prevent air from escaping from the tyre.


  5. Take one of the puncture-repair plugs, fold it exactly in half and thread the resulting U-shaped section of the plug onto the tool for inserting the puncture repair plug into the tyre.  Place the tool aside on a clean surface with the plug threaded on it.


  6. If necessary, inflate the tyre again to its normal air pressure in order to prepare the tyre for inserting the puncture-repair plug.


  7. Pull the rasping tool out of the hole in the tyre and immediately take the tool with the plug threaded on it and push the plug 2/3 of the way into the tyre (according to the length of the folded plug) before much air has a chance to escape from the tyre.  You’ll need to use a lot of force to push the plug into the tyre.  It’s often best to do it in stages by first plugging up the hole so that no air escapes and then progressively pushing the plug further into the hole.

    It’s best to visually check how far the plug needs to be inserted into the tyre before pushing it in, by measuring off 1/3 of the length of the folded plug, in order to avoid pushing the plug too far into the tyre.  The plug should not be pushed more than 2/3 of the way into the tyre according to the folded length of the plug.


  8. After pushing the plug 2/3 of the way into the tyre according to its folded length, pull the tool on which the plug was threaded directly out of the hole in one quick motion without twisting it.  You will probably need to exert a bit of force to pull it out in this way.  Don’t hit yourself in the face with your hand when you pull it out!


  9. Remove a blade from a utility knife and cut off the 1/3 of the length of the folded plug which remains sticking out of the plugged hole, so that the plug is exactly flush with the surface of the tyre.


  10. Inflate the tyre to its normal air pressure using a foot pump and tyre pressure gauge or other source of air such as an air compressor.


  11. If it was necessary to remove the wheel with the punctured tyre from the vehicle, put the wheel back on the vehicle.  Tighten the wheel nuts progressively in a crisscross pattern in stages and use a torque wrench if one is available to tighten the wheel nuts to the torque specified in the owner’s manual for the vehicle.


  12. Admire your handiwork and breathe a sigh of relief that you won’t have to keep inflating that tyre every day any more.  Problem solved!




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Copyright 2016 Andrew Mackinnon.  All rights reserved.