How to use tyre sealant

Flat tyres are a common problem that happens at the worst of times. Whether you're stranded at the side of the road or prepping for a long journey, knowing how to use tyre sealant can be a useful tool in your kit. This blog will cover how tyre sealant works, how long it can last, whether a tyre can be repaired after using sealant and how to apply it correctly.  

 

What Is Tyre Sealant and How Does It Work? 

Tyre sealant is a liquid product designed to temporarily seal small punctures in tubeless tyres by creating a plug inside the tyre. The way it works is that when a hole appears in the tread area, the escaping air drags the sealant toward the puncture. There, fibres and binders contained in the product build up and form a plug that helps prevent further air loss.  

This process is not intended as a permanent fix, but rather as a way to get the tyre to a safe location or garage for a full repair. Many sealants are designed to work only on holes that lie within the tread area and not on sidewall damage or on large tears. 

 

How Long Does Tyre Sealant Last? 

The lifespan of tyre sealant depends on its brand, the conditions inside the tyre and how often it has been used. Some sealants are designed for single use, once they’ve sealed a puncture, they typically can’t seal any additional holes and will need to be replaced. Others are meant only for emergencies and specify driving distances and speeds. For example, one test noted using sealant to allow the driver to continue for up to 100 miles before a professional check.  

It’s important to check the expiry date of the sealant product and to replace it if the bottle has been open for a long time or used previously. Over time the liquid may settle, or the active ingredients may become less effective. 

 

Can a Tyre Be Repaired After Using Sealant? 

Yes, in many cases a tyre can still be professionally repaired after sealant has been injected. However, there are factors to consider. Some tyre repair workshops may charge extra to clean out the sealant residue before working on the tyre. In addition, if the sealant has been used as an emergency measure and the tyre has been driven for a long distance or at high speed, the internal structure of the tyre may be compromised, and the safest choice may be replacement.  

It’s essential that the repair is carried out by a qualified technician and that the damage is within repairable limits. If the sidewall is cut, the bead is damaged or the hole is too large (for example larger than about 6 mm), sealant is not a safe substitute for a professional repair. 

 

How to Use Tyre Sealant: Step by Step 

First, make sure you are parked in a safe location away from any traffic. Begin by checking the tyre for visible damage and make sure the valve cap is removed. If the manufacturer instructs, deflate the tyre slightly before attaching the sealant applicator. 

Most sealant kits or bottles will have instructions on how much to add. Once the sealant is injected, reinflate the tyre to the recommended pressure specified in your vehicle handbook or on the door‑frame label. Then drive a short distance (at a reduced speed) to distribute the product evenly inside the tyre so it can coat the interior surface and fill the puncture. After the trip, inspect the tyre and monitor pressure. If there is continued loss, visit a tyre specialist such as Merityre.  

Always keep in mind that using sealant is often meant as a temporary fix only. You should have the tyre professionally checked at the earliest opportunity at your local Merityre branch. 

 

Important Tips and Warnings 

Using a tyre sealant does not replace following normal tyre maintenance routines. You still need to check tyre pressure regularly, inspect tread depth and look for damage. Also, sealants may interfere with tyre pressure monitoring systems (TPMS) if they are not specifically approved for use with those systems. 

If the puncture is in the sidewall or the tyre has already been driven while flat, the use of sealant is not advisable. In those instances, the safest solution is a new tyre or a professional repair at a tyre workshop. 

 

How Long Does Tyre Sealant Last? 

Tyre sealant is intended as a temporary fix, not a permanent repair. The longevity of a sealant repair depends on the size of the puncture, where it is, and the type of sealant used. In general, you can expect it to last around 50 to 100 miles, just enough to get you safely to a tyre garage. 

It’s important not to delay a professional inspection. Continuing to drive on a sealed tyre for too long can result in: 

• Uneven wear 

• Reduced grip and handling 

• Worsened damage, potentially making the tyre unrepairable 

 

Pros and Cons of Using Tyre Sealant 

Here’s a quick look at the benefits and limitations of tyre sealant: 

Pros	Cons
Quick and easy temporary fix	Not suitable for large punctures or sidewall damage
Saves you from changing a tyre roadside	May damage TPMS sensors if not TPMS-safe
Compact and space-saving	Some garages won’t repair tyres that have used sealant

 

Final Tips for Using Tyre Puncture Sealant 

• Check your tyre pressure after using sealant and top up if needed 

• Replace sealant kits every 4 years or after use 

• Drive cautiously and avoid high speeds after applying sealant 

• Don’t rely on sealant for long distances, visit a garage as soon as you can 

Tyre sealant can be a lifesaver in the short term, especially when you’re caught without a spare. Just make sure you use it correctly, know its limits, and follow up with a professional inspection. 

 

Contact Merityre for Trusted Advice  

Tyre sealant is a handy emergency tool that can get you moving again and reduce the need to change a tyre at the roadside. However, it is not a long‑term solution, and it does not replace a professional tyre repair or replacement when necessary.  

At Merityre, our specialist technicians are here to help you choose the right repair or replacement and ensure your vehicle stays safe on the roads. 

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