Puncture! Changing a wheel with a flat tyre (2019 Ford Focus)

Puncture! A ‘real time’ demonstration of changing a wheel with a flat tyre on our 2019 Ford Focus training car. Intended for novice / L-drivers who have never seen a wheel being changed before - for awareness only.

With modern cars becoming ever more reliable, Flat Batteries & Flat Tyres remain the two most common causes of break down.

Reading your own car’s manual on Jump Starting and Tyre Changing procedures, and familiarising yourself with your car’s boost starting connection points and jacking point locations, spare wheel, jack & tools BEFORE you become stranded is therefore good practice.

* * This tragic case on the A34 highlights the importance of the advice we give on calling a professional recovery service rather than attempting a wheel change at the roadside or hard shoulder of any major road. The case also highlights the very real dangers of illegal phone use at the wheel, and the human & legal consequences of doing so:

This video runs in ‘real time’ to give you a good idea of how long a wheel change takes. It is intended for illustration/entertainment only and should not be relied upon. Refer to your own car’s manual for car specific procedure and safety warnings, and seek help from a competent person if attempting these techniques for the first time.

During this video we discuss:

1. Identifying a flat tyre from the car walk-round checks and modern tyre pressuring monitoring system.

2. We discuss recovery options from break-down services (AA, RAC, Green Flag, Local Garage) to dedicated mobile / road side tyre fitting services.

3. We also mention tyre inflation aerosols and their limitation to sealing small punctures, not larger gashes.

4. We then look at fitting a narrow width temporary spare tyre following the procedure described in the Ford Focus hand book.

5. We then inspect the tyre to identify the cause of it’s deflation.

Some cars are fitted with ‘Run Flat’ tyres which have ridged side walls enabling your to drive up to 50 miles at reduced speed on a completely deflated tyre.

‘Thru the valve’ options which doesn’t require the removal of the valve core, will be easier & safer to use on a dark rainy road side as these videos explain in detail:

Sealant & Inflator Kits review and summary:

Slime & Continental Sealant Inflator unboxing comparison:

0 - 60 psi Slime -v- Continental Sealant Inflator comparison in ‘real time’:

[tonyjack]

This is a brilliant real time well explained video

[joystation]

Good demonstration of how to change a wheel and great tip to keep a set of mechanics gloves in the boot. All car owners should be able to change a wheel as even if you do have breakdown cover, you might get a puncture in an area with no mobile phone signal or your phone may be out of juice, Sods Law says you will have a breakdown when your phone is dead. Car owners should also check from time to time the pressure in their spare tyre. I laughed when you said you would have too see what a tyre professional had to say about if the tyre could be repaired, if a screw or nail has gone through anywhere remotely close to the shoulder / edge of the tyre, your Professional will cover their @rse by declaring the tyre unrepairable, but as luck would have it, you have taken your wheel to a place where they have lots of new tyres for sale. Finally, I'm pleased to see that you were not guilty of it but a plea to everyone who removes a wheel, take care of your expensive alloy wheel, do not put (or throw) it down on the ground on it's outside face, ground / tarmac is hard, alloy is soft and easily scratched by hard things, so lay it down on it's inside face.

[drivingvideos]

DVSA L-Test Tyre ‘Tell Me’ Questions:

DVSA Question: ‘Tell me how you’d check the tyres to ensure that they have sufficient tread depth and that their general condition is safe to use on the road’.

DVSA Answer: ‘No cuts and bulges, 1.6mm of tread depth across the central three-quarters of the breadth of the tyre, and around the entire outer circumference of the tyre’.

DVSA Question: ‘Tell me where you’d find the information for the recommended tyre pressures for this car and how tyre pressures should be checked’.

DVSA Answer: ‘Manufacturer’s guide, use a reliable pressure gauge, check and adjust pressures when tyres are cold, don’t forget spare tyre, remember to refit valve caps’.

[drivingvideos]

Failure Mode and Effects Analysis (FMEA) is a structured approach to discovering potential failures that may exist within the design of a product or process. Failure modes are the ways in which a process can fail. Effects are the ways that these failures can lead to waste, defects or harmful outcomes for the customer.


Given the very limited technical / mechanical experience of our young / novice L-Test drivers, simplicity of operation was a key criteria. All kits we explored worked on the same broad principle of injecting a latex based ‘sealant’ formulation, through-the-valve and then re inflating the tyre with air (or propane / butane gas in the case of aerosol products). The ability of the Inflator Compressor to fill air into the tyre through the valve more rapidly than air could escape through the puncture hole 🕳️ is key to the success of these products, as getting the tyre re-inflated and driving is crucial as the rotational forces are needed to distribute the latex sealant into the puncture. So, our 0 - 60 psi ‘race’ was exploring an importance performance parameter of these products; insufficient air / gas to adequately re-inflate the tyre would result in a ‘Failure’. A faster pump also minimises the time ‘at the roadside’ (by many minutes in our testing), so a significant safety consideration.

The other key potential ‘Failure Mode’ was the Inflator Compressor’s electrical draw flattening the car’s starter battery 🪫 to the point when it could no longer start the car’s engine, thus leaving the driver as stranded as the original puncture had! Hence our preference for products which could be used with the engine running, and thus the alternator recharging the starter battery.

Desk Research on real world consumer experiences (predominantly shared via You Tube videos and car forum discussions) and independent consumer testing (e.g. Project Farm) confirmed that the sealing capabilities of the latex formulations in most of these products do work if used in accordance with the manufacturer’s instructions, and within the limitations of their intended use i.e. small nail / screw tyre penetrations 5mm maximum, in the main tread area.

The final ‘Failure Mode’ evaluated was that of ‘operator error’ viewed from the perspective of our Novice / Inexperienced L-Driver in the “panic” situation of their first puncture. Clarity on user instructions and an intuitive product design were all considered in this context; again drawing on the real world experiences of disgruntled customers who posted their negative experiences on-line (and who had often not followed the manufacturer’s instructions). Caveat Emptor is not an acceptable excuse, in my opinion, in a product designer / brand marketer leaves a young person in a vulnerable position at the road side due to poor product design or clarity on instruction (written or web-based video format). The other key ‘Failure Mode’ for novice drivers potentially in older First Cars is the requirement on all these products for a 15amp fused power (‘cigarette lighter’) socket; older cars often has 8amp - this needs to be made very clear to the consumer.


A ‘thru-the-valve’ pot & tube sealant canister paired with a rapid tyre inflator capable of being used with the engine running to avoid flattening the starter battery 🪫.

Flat Tyres 🛞 & Flat Batteries 🪫are the two most common causes of Winter ❄️ breakdowns.

Punctures increase as potholes 🕳️ open up through Winter ❄️

Are you prepared? Would you know what to do?



⚠️ Any road side car breakdown recovery attempt can be incredibly DANGEROUS with a risk of Death or Life Changing Injuries: impact from passing vehicles, chemical or electrical burns, crush injuries, explosions, etc. ⚠️

⚠️ IF IN DOUBT, CALL SOMEONE OUT! A BREAKDOWN RECOVERY PROFESSIONAL ⚠️

[drivingvideos]

Do not confuse this LEGAL minimum, with the SAFE minimum. Particularly when the car is being driven by young & inexperienced drivers who may make ‘rookie errors’ of judgement on speed, distance, severity of bends, weather & road conditions.

[drivingvideos]

As John Cadogan illustrates, Punctures rarely happen at at good time, in a good location. Are you prepared / equipped for possible scenarios?

No spare tyre? Why is nobody talking about this? - Auto Expert John Cadogan