Very Slow Puncture Repair ?

My wifes Mini has a slow puncture on the front tyre . We had the alloy rim cleaned and tyre refitted a few weeks ago , but we still have a slow puncture , albeit slower now . Its going from 32 psi to around 27psi in around two weeks. I can't be bothered to try another tyre refit.
Now in these days of no spare tyres there are several sealants......

• Holts tyre weld.
• Slime ( I have this with a small compressor kit as standard on my car)
• Goop - now this is a water soluble sealant - Vid below.

Anyone experience on this to fix a small tyre rim leak ? TIA

 

I think but not sure, them tyre sealants are only for emergency only, if you use them and still it leaks it will be a new tyre, but i could be wrong

You might find that the alloy wheel is porous, which you can get them cleaned and repainted/or what ever they do to the wheel

 

Cant say that I have ever come across a tyre that holds exactly the same pressure all the time.
If they did why would service stations have air lines?
I check all mine, not as often as I should, and put some air in from time to time.

That said, have you had the valve replaced?

 

A good, preferably independent tyre shop will remove the wheel, dunk it in a giant bucket of water, and watch for bubbles.

If the alloy was cleaned and greased with that white stuff, then my next prime suspect would be a leaky valve, but if it is a slow puncture you'll need to know where it is, as it could rip and blowout depending on where it is.

Incidentally, there's a simple diy way to diagnose a leaky valve. Remove the dust cap. Then put a tiny blob of ordinary washing up liquid on your finger. Run it across the top of the valve so as to coat it with a thin film of washing up liquid. Then watch for a minute. If bubbles form, the valve is duff. However if bubbles don't form, it doesn't necessarily rule out the valve. It could be that the valve is not seated right and is leaking from the base. It's just a simple test that says either definitely just the valve (bubbles form) or could be leaking anywhere (no bubbles).

 

Id squirt a drop of oil/gt85 into the valve ,then open and close it , then it may seal better.?

 

Thanks all , they are all new tyres with new valves . I really don't want to sit in the bath with a mini wheel looking for bubbles I'll stick this Goop in one tyre , and see if it brings the pressure drop to an acceptable level.
@WeeTam , good stuff that GT85 ! It is a spray lubricant , where as WD40 is a spray solvent . Must get some more when I see it.

 

Before using an aerosol instant repair magic, carefully read the label. I'm pretty sure that they're meant as a last resort, to get you home if you get a flatty in the middle of nowhere, and are not sold as a safe long term fix.

 

I had slow leak on new tyre AND Valve
As above tyre fitter took it off, cleaned the alloy, and painted on the white stuff, refitted tyre
Still slow leaking
Visited again and it proved to be the new valve seating had a rubber rag on the base

No more problem

Jack McH

 

With the wonders of the internet , you can soon research tyre products. Holts , Slime and Continental are get you home repairs to last around 100 miles before full repair. Goop is a puncture preventative solution , which has extremely good reviews as a rim sealer . Its worth a pop on one wheel

 

If those new tyres had just been fitted to my car, then I would have gone back to the place that fitted them to get the job redone correctly. On no account would I use any of the products mentioned in this thread. Tyres are meant to seal against the rim.

Remember that small leaks can turn into big ones, and a sudden deflation can have serious consequences for not only family members, but members of other families also.

 

Well I did have two tyres refitted by the garage . One seals perfect now , t'other has a small pressure drop over two weeks . Which is 99% certainly , alloy wheel rim leakage , a very very common problem . These leaks do not turn into big leaks and can be repaired by puncture sealant . Lots of manufacturers fit temporary repair kits as standard , Audi , my last Ford and my new Mitsubishi to name a few. The puncture preventative solution is a water based development of this.

 

Sounds like its sorted with the refit. Good advice to avoid the 'emergency' puncture repair solutions.

They do say check tyre pressures weekly - which is good advice - the pressures set on one day will fall or rise with the ambient temperature.

 

If the rims are still leaking after being properly cleaned and with that white tyre sealant used, then I think it's time to have the wheels properly looked at. Porous alloy is brittle alloy. If it develops into a hairline crack, the tyre will deflate quite rapidly.

In my experience though, the biggest culprit is an inadequate rush job when the tyre fitter cleans the rims. I've seen them do it. Tyre off, one quick lap with a scrubbing brush, tyre back on, still leaks. I had that happen on my last car. I took it back to the tyre place. It was one that offered free replacement if the tyre failed within a certain time. Miraculously, they found the tyre was fine, and this time a proper clean of the rim solved the slow leak.

 

Am I the only one on here with a slow alloy leak ? And how many of us check the tyre pressure every week - be honest

 

Well I've had alloys on every car since 1980, never come across the problem.
Never did check every week though.

I've got a deflation warning now on my car so dont bother checking, it does work because I had a puncture a few months ago and got a warning when the tyre dropped 5 psi.