I had a tire with 4 nails in it and my local tire repair shop removed the nails and patched the tire for $15. But I did some reading and found PUNCTURE REPAIR PROCEDURES www.rma.org/wp-content/uploads/prp_wallchart1111.pdf on the Rubber Manufacturers Association site and wondered how the tire shop could do all of these many steps to fix 4 holes for just $15. I went back today and talked to the owner. Very friendly and cooperative, he took me into the shop and showed me what he uses. Basically, for regular small punctures (might have said up to something like a 10 penny nail), he uses Centech patches inside the tire, with no plug and that they were the highest quality and so flexible that they could be used near the sidewall. When I pointed out that RMA stated that a patch without a plug is not a proper repair, he showed me a plug/patch combo (like these pictured at www.fixtires.com/prodimages/250ul.png) and pointed to the part of the plug nearest the patch and told me to fix a small nail hole, you do not want to drill the hole larger just to accommodate this plug. I also asked him about the danger of water getting in the unplugged hole and, as the RMA cautioned, possibly rusting the steel bands. I don’t remember his exact reply, but clearly, he did not consider this an issue with most small holes.
At this point my question is: How safe can this repair be that does not follow the RMA’s warning -
“NEVER use only a plug (stem) or never use only a patch to repair a puncture. The injury must be completely filled with a suitable vulcanizing material or rubber stem and a patch must be applied to the inner liner to prevent air loss.”
NOTE:
The shop is a family owned business that has been in our small city [aprx 60,000] for decades. They have 24 customer reviews online and a 4.6 rating with only 2 people having anything negative to say about them (and no complaints about tire repairs gone bad). Many report that these folk are not out to make a shady buck. They charged me $30 to remove/repair 5 nails/screws from 2 tires. The owner had originally told me he might have to charge more.
www.nwsalesgroup.com/product/233.aspx “Centech is the most advanced radial tire repair system ever developed. Crown, shoulder or sidewall injuries in passager and truck tires can be repaired with Centech center over injury radial repairs. A special compound and design allow the repair unit to flex and resist heat, assuring a permanent repair.” (these are the patches he showed me)
“*All Centech repair units must be used in conjunction with the proper injury filler material.” (does not say if this is Centech’s statement or nwsalesgroup.com’s)
I think they mean that if/where the puncture exposes the steel bands they will rust. A hole through the tire will come close to - if not hit - steel bands in the tire.
My offhand guess is that by the time the rust starts to be a significant problem for a tiny hole, the tire is end of life. After all, it’s not like a drilled bigger hole that probably bares and possibly severs more steel bands. If one wire of a radial fails (which it would in a big hole anyway?) how serious would it be?
If I spent a lot of time at highway speeds or never examined my tires, maybe I’d be more careful with repairs.
And a procedure done wrong is only a problem if it causes a problem and someone sues - and why sue if they don’t have enough assets to cover the lawyer’s bill?
Based on the common practice (and ensuing success rate) of nearlyh every tire-patching professional and amateur I’ve known, the RMA’s mandated procedure must be outrageously conservative. Clearly a “belt and suspenders” approach. I’ve never known a tire guy or a layperson to go to those extremes, and tires which have been plugged or patched (but not both) rarely seem to cause problems later.
There may be cases where doing it the “right” way is critical. Something too near a sidewall, or a tire used for particularly demanding purposes. But for your everyday nail hole, common practice seems to indicate that you can get away with less than the RMA’s highly conservative procedure.
From my experience, making a small hole larger to fit a plug patch is going to make the repair more likely to fail. Just let the hole as is and put a simple patch on the inside.
While I appreciate your comments, I feel compelled to reject the last one with this edit: And a procedure done wrong is only a problem if someone ends up injured or killed. A lawsuit never entered my thinking.
I had wondered how much rust could take place over the life of the tire, but water’s affect on the bands was given as one reason to use a plug. Also, if you read the Centech info at the bottom, evidently a plug is suggested/required with their patch.
Safety Problems Associated With Tires “There is no direct evidence in NHTSA’s crash data files that points to defective or sub-standard tires as the cause of a particular crash…” but this page does present (2001?) Tire-Related Crash data and information - www.nhtsa.gov/cars/rules/rulings/upgradetire/econ/TireUpgradeIII.html
