If your tyre keeps losing pressure but there’s no visible puncture or valve damage, the problem could be a rim leak. This guide explains how to identify when air is escaping from the tyre rim, what causes it, how to fix the issue safely, and how to prevent rim-related leaks in the future through good maintenance and careful driving.
There are several reasons why your tyres might lose pressure over time and as you drive.
A puncture or damage to the tyre tread is often caused by hitting a pothole or obstacle on the road, while a damaged tyre valve can lead to the gradual loss of air known as a slow puncture. Another cause of pressure loss is air leaking from around the tyre rim – that is, the area of beading that connects the rubber of the tyre to the outer edge of the wheel rim.
Here’s a quick guide on how to identify the cause of pressure loss from your tyres and what to do to fix it.
How to Know if Air is Leaking From the Tyre Rim
The biggest cause of air and pressure loss from the rim of your tyres is deterioration and corrosion. Because of this, this issue typically affects older tyres – and is exacerbated by damage caused by potholes and lumps and bumps on the road.
Arguably the easiest way to isolate and identify the cause of pressure loss from a tyre is trial and error. If there is no obvious puncture damage on the tyre, and the tyre valve seems to be holding air in, then the chances are the issue is centred around the rim of the tyre.
The Role of Tyre Beads in Pressure Loss
Tyre beads are what ensure that the tyre is connected tightly to the wheel.
If the beads become damaged, either because of corrosion or because the wheel is deformed by a pothole or obstacle on the road, then this airtight seal breaks – and air can escape. It can also be caused by loose debris getting in between the tyre and the rim, which affects the integrity of the airtight seal.
NOTE: There is no way to replace the actual beads of a tyre without replacing the whole tyre, so this kind of damage cannot be fixed but rather must be replaced.
How to Fix a Leak From the Rim of a Tyre
Step one is to identify the area of the rim which is causing pressure loss.
The best way to do this is to remove the tyre from the wheel and lie it with the tyre valve pointing upwards. Add soapy water to the rim of the tyre and look for the bubbles – this indicates where air is escaping from.
Once you know where the damage is, empty all air from the tyre and remove the tyre from the wheel rim.
Thoroughly clean the wheel rim and the tyre, to ensure that all debris has been offset and removed. You can then replace the tyre and refill it with air, checking the pressure as you do so to see if it holds.
If it does – you’re good to go!
If it doesn’t, there’s a chance that your tyre has a puncture or damage somewhere else. You can either try using a tyre DIY repair solution to get back on the road and drive to your local garage or call for roadside assistance.
