Very Slow Puncture

Adamvanman · Dec 19, 2020

I had new tyres fitted in September but like a lot of people I have not used the van much, however we went out last weekend and the tyre pressure warning light came on so when I got home I pumped tyres to correct pressure however over the past week the pressure has gone down again , I took the wheel off and inspected it and nothing obvious so I took in to our local tyre centre who said they have equipment to find slow punctures but nothing was found . Do you think I just need to buy a new tyre ?

Ch1pbutty · Dec 19, 2020

Adamvanman said:
I had new tyres fitted in September but like a lot of people I have not used the van much, however we went out last weekend and the tyre pressure warning light came on so when I got home I pumped tyres to correct pressure however over the past week the pressure has gone down again , I took the wheel off and inspected it and nothing obvious so I took in to our local tyre centre who said they have equipment to find slow punctures but nothing was found . Do you think I just need to buy a new tyre

Try having the tyre removed / refitted, might not be seated properly on the rim. If tyre is fine it might be a crack on the alloy which can be checked when the tyre is off.

Alan Andrews · Dec 19, 2020

Ch1pbutty said:
Try having the tyre removed / refitted, might not be seated properly on the rim. If tyre is fine it might be a crack on the alloy which can be checked when the tyre is off.

I agree about having the tyre reseated. They also apply a sealing solution before the tyre is pumped up to seal against minor air leaks in the seal.

Also try removing the wheel and placing the whole wheel in a solution of soapy water. You might need to use a plastic sheet or tarpaulin to create a tub that the wheel can sit in.

The soapy water will allow you to see any air leak. Then mark the wheel and tyre position.

I have had the same problem with a couple of wheels on my daughters car. This is how I discovered where the leaks were. On inspection later we found it was the result of having kerbed the alloys on the inner edge. Once filed smooth the tyres were refitted and no problem since.

Adamvanman · Dec 19, 2020

The tyre place did put it in the 'bath' and showed me both sides of the wheel whilst pumping air into it, and zero bubbles came to the surface. Strange

WelshGas · Dec 19, 2020

Adamvanman said:
The tyre place did put it in the 'bath' and showed me both sides of the wheel whilst pumping air into it, and zero bubbles came to the surface. Strange

Did they check the valve?

GSX1300R · Dec 19, 2020

If you still have a problem after exhausting all avenues you could try Slime. it’s a tyre sealer that prevents punctures. used to use it on my motorbike..Only thing is that it can be a bit messy when it comes to changing the tyre.

briwy · Dec 19, 2020

Aloy wheels can go porous sometimes. As mentioned above might be worth trying a can of puncture repair and see if that cures it. Punctures don't get better, only worse.

Meoncoast · Dec 19, 2020

have had valve failure in past.

kurienp · Dec 19, 2020

Adamvanman said:
I had new tyres fitted in September but like a lot of people I have not used the van much, however we went out last weekend and the tyre pressure warning light came on so when I got home I pumped tyres to correct pressure however over the past week the pressure has gone down again , I took the wheel off and inspected it and nothing obvious so I took in to our local tyre centre who said they have equipment to find slow punctures but nothing was found . Do you think I just need to buy a new tyre ?

Slow punctures are a pain, and the only method to solve will be to take a structured approach. A tyre change should be one of the last options.

I would:
1. Change the valve stem and see if that sorts it out. Also do the next step along with that to save on tyrw fitting costs.
2. When the tyre is being mounted, use a tyre rim sealant. (Not mounting paste but rim sealant) If the tyre fitter does not have it, you can pick up a tin for about £10 off ebay
3. Failing that, pick up a used tyre to mount to your rim and see if that sorts out the issue.
4. Last of all, if none of the above have helped, go to a.specialist rim mechanic to check if it is a problem with the rim.

It is a task that will need a step-wise logical approach.

Sent from my Pixel 2 XL using Tapatalk

Phil P · Dec 19, 2020

The advice suggested is spot on, start off simple to most complicated.
But my guess is the tyre bead sealing or valve fault.

Elmo3 · Dec 19, 2020

How old are the wheels? Sounds like a porous alloy.

Phil P · Dec 19, 2020

Some alloys suffer from this, many years ago it was a known issue on Audi TT s and warranty or goodwill paid for new?

silversurfer · Nov 4, 2023

I've had a very slow puncture for a while now (ok - actually years) . I have previously taken it to my (friendly and good) tyre place who checked the tyre. No obvious holes. Took the tyre off, cleaned the rim, painted on gunk (not sure what), put it all back on.

Still leaked.

But nothing beats an amateur with the time to do the job slowly and properly. I took the wheel off, immersed it in clean water in the zinc bath we have and finally spotted tiny bubbles coming from around the valve seat. And looking closely you can see evidence of corrosion around the opening.

I also found that the inner edge of the tyre was down to textile in one spot and the tread on the inside inch is worn off. It's difficult to see that inner edge, glad I spotted it, because the MOT in September didn't mention anything.

If I can get the scissor jack back in that polystyrene holder thing I'll be even more please.