To Repair a Puncture or not?

[harrier]

As a follow on from the earlier "Tyre advise" thread, having had one mid tread puncture on one rear tyre and now loosing 0.5Bar a week with no visible puncture on the other rear tyre, I have been keen to get a definitive answer on what I should or should not do when faced with a puncture that appears to have sealed itself. Audi has fitted the PE, mine at any-rate, with Continental ContiSport Contact 5P tyres and although the tyre with the obvious puncture seems fine now, these are ContiSilent (marked) tyres, not ContiSeal. Discovering the correct and safest course of action has become more imperative in the light of lacking or erroneous advice from all three suppliers and fitters of tyres that i have so far approached!

It took quite a bit of effort to get any contact phone number (rather than email message or "Chat") for any one at all at Continental Tyres in the UK (my German is far too rusty), but when I did get to talk to a representative they were very quick in getting a tyre technician to call me back to helpfully answer all my questions.

The answer is that if and when ContiSeal or ContiSilent tyres get penetrated causing a puncture, they BOTH have a sticky sealant layer that hopefully will seal the puncture or help to keep if from rapidly deflating. It is just that the ContSilent tyre has a thinner,less effective layer, that is chiefly there to keep the sound deadening and insulating white sponge layer in place and it doesn't cover quite as much of the tread either. When a puncture is detected, the purpose of the sealant is to enable the driver to drive the car at leisure to a garage for tyre REPAIR, hopefully without the need for a roadside repair or spare wheel. BOTH types of tyre C.-SEAL and -C.SILENT do NEED TO BE REPAIRED! The reason for this is that penetration of the tyre, by a foreign body, such as a nail, will with time allow WATER INGRESS through the cross-ply and ultimately CORROSION of the metal wires and a potentially very dangerous WEAKENING of the structure of the tyre!

I will, therefore, be getting my tyres repaired (as per Continental's online PDF Instructions), despite the (1st) tyre apparently sealing the puncture and remaining correctly inflated since then. But first the garage and I have also got to have another go at locating the site of the puncture in the 2nd tyre. This may be helped by the fact that eventually the sealant is likely to appear emerging through the perforation in the rubber, I was told.

P.S. I was also informed that tyre producers aren't, unsurprisingly, allowed in law to publish an expected mileage figure for their tyres, which one might think would be helpful, as there are always going to be far too many variables for a direct comparison with other manufacturers' products. Also, I have learned that Continental are the only company that manufacture all the parts needed to construct a car in its entirety, including naturally its tyres!

I hope this helps?

[chunky79]

I have never had a tyre repaired on my cars, never. I even refuse to have them on my works van now.
Different strokes for different folks, but I don't want to be doing whatever silly speeds we all like to do with a repaired tyre under me. What's a tyre £250 Max?

[harrier]

The C7 has 285x30 R 21's all round and here/Blackcircles were £290 before Christmas, when I last looked, and now the ContiSilent are £309, not a lot less if you don't want the sound absorption.

Often one may be quite unaware that a tyre has been penetrated and so part of the development of a sealant, I expect, has been to seal these leaks or potential leaks until they are found or reveal themselves and to slow any deflation. Our cars aren't exactly on F1 rubber designed to have limited life. The radial wire mesh structure gives enormous strength, that's not going to disappear with a small nail for example. To chuck them in every case would be to discard piles of research, so again, each puncture on its merits and each to their own.

Have any members ever had a sudden catastrophic blow out at any speed, caused by a small puncture old or new, repaired or not, I wonder? I have had a rapid loss of pressure, due to a rip in a tyre, on a Fiesta XR2 at 70mph or more, years ago. After increasingly fishtailing the car shot off the dual carriage way at 30* to the road (as witnesses by the tread marks on the grass later), across the verge and then into a load of saplings in the middle of the wide central reservation. Fortunately my crash was not into the nearby, huge, horizontal oak tree felled a short time previously by the "Great Storm". Years later another big puncture in a rear tyre, this time in my RS4 B7 at over 80mph, if I recall, caused a gradually increasing rear vibration. Pulling over as soon as possible, I found the tyre completely flat. I thought I'd creep the car 100m to a lay by for safety, as there was only a meter or two of hard shoulder, only to find the wheel rim had quickly sliced through the tyre and I couldn't get there. Then, having undone the wheel bolts, whilst avoiding being hit by passing cars, I found I just couldn't get the wheel off the axle, but that's another story. I can't say I have ever had a small puncture cause a blow out.

[skirs6]

Controversial ????? I only ever buy part worns !!! Always premium brands with correct ratings for the car and never had a problem but have saved a fortune. Now on my third RS6

[audi_driver79]

I have no problem with tyres that have a puncture repaired as long as I trust the garage. I exceeded maximum speed with a repaired tyre and I'm still here.

[harrier]

Having spoken today to a head Audi technician I respect, I am told that, despite Continental and other manufacturers being confident that their tyres once punctured and then repaired properly as per their stipulation are perfectly safe for continued use, Audi UK has instructed dealers that they are concerned that anything that has punctured through may have weakened the wires in the steel belts. They therefore insist that such tyres are replaced and NOT used.

Not having had a pucture in some years, my new car now has a second tyre with a puncture which my "tyre" garage and I have been unable to locate, but which is loosing approximately 0.5 BAR a week. I have decided to renew both and get the two punctured tyres repaired and keep them as potential "temporary" spares. I'll feel safer and happier and I'll have two rear tyres with the same depth of tread.

[chunky79]

Are you sure you have punctures? Sure your 21'' wheels are not out of round??

[Bit_evl]

Agree with chunky.

When mine were eccentric the front one lost pressure slowly.
When you go to get them changed ensure you check them for being round in all the right places !

[harrier]

Will do, thanks.

On that subject, our Mini CooperS had its first 10,000 service a few weeks back. May partner sat in the stealers for more than two hours and chatted to the staff. It was only when she got home and looked at their report that she realised that it stated that the car needed urgent attention to one alloy which was buckled! The tyre and alloy wheel both appear completely unmarked. They have offered a new one for around £250. The Wheel Specialists, who I have found take more care than anyone I know when it comes to wheel refurbishment, say they can correct it: cost approx. £60 + £30 if you need the tyre taken off and replaced.

Opinions on buckled wheel repair please?

[Bit_evl]

Having just been through exactly this on the RS6 just recently (3 buckled) I am in the position where Audi insisted first round was an attempt to correct the existing wheels. The local company in Reading was used and did a reasonable job of it. There is still a tremor through the wheel and it is not as good as it was prior to 5000 miles but it is no longer shaking like a 200,000 london taxi.

My previous CL600 had a pot hole experience thanks to the poor repairs of our local council and bent the rim of one of its 20" AMG alloys. This was corrected by the garage and was actually very good. They did say to move it to the back and so remove it from the steering as well.

If you have the cash to spare I would still go new.