Despite thousands of written words, numerous seminars and countless hours of in-shop training programs, many people still have a hard time believing that you can safely, effectively and permanently repair almost any type of tire injury. A recent newspaper column in The Long Island Newsday, offered the following advice to motorists:
``If the sidewall is punctured, the tire should be discarded. Repairing a puncture anywhere other than the belted-tread area should, for the most part, be frowned upon. But there is an exception. If you can find an inner tube designed for use in radial tires, the tire shop can patch the sidewall of the radial-provided the puncture isn't too large-and insert the tube inside the tire.'' The writer concluded his article by recommending use of a repaired radial only as a spare.''
On reading this nonsense, I wondered what planet this guy was from. Where did he come up with such misinformation?
I get the impression that such so-called ``experts'' feel puncture repairs are little more than jamming a plug or string repair into the tire from the outside.
That may be the reason so many of these ``knowledgeable authorities'' continue to tell the public that repairs can be accomplished only in the tread area. Even then, they contend, the repair has to fall inside the major tread grooves. These ``experts'' say repairs should not be attempted in the shoulders or sidewalls.
I had thought these ideas had gone the way of the Edsel, but it seems they are still around.
There is no effective method of preventing a sharp-pointed object from penetrating the tread or sidewall of a pneumatic tire, which is only as good as the air pressure that's in it. Given that premise, we must also accept the fact that penetrations will occur and that the air pressure within a tire will escape.
With a radial tire, a small penetration does not reduce the strength of a tire, it only lets the air out. Even if a sidewall split occurs between the cords, it is of little consequence because it is only rubber damage, not structural damage to the casing. In a radial tire, real damage occurs only when the tire has received a fracture across the cords.
At this point, I might also mention that even though puncture and section repairs have been made successfully in both tread and sidewall areas of passenger radials, I have not been a believer in section-repairing them. That's because the economics have not been favorable and the appearance of the finished product seldom is satisfying to customers.
However, putting a tube in a tubeless tire defeats the purpose of tubeless technology-which is to provide a cooler-running tire.
The tubeless concept has been around for quite a long time. It was first patented in 1891. B.F. Goodrich first marketed a tubeless tire in 1948. Firestone developed the first tubeless truck tire in 1953 and Michelin initiated production of a tubeless radial passenger tire, the ZX, in 1964.
The butyl liner of a tubeless tire may be considered the ``tube'' of that tire. Placing a tube inside a tubeless tire is like putting a tube within a tube. The friction and subsequent heat buildup associated with tubed tires returns.
There are no ``free lunches'' when it comes to repairing tires, whether it is a puncture or section repair. Unfortunately, few people really know how to repair tires correctly, and even fewer can properly repair major injuries.
Although every tire injury and tire repair is a little different, there are some basic guidelines and fundamentals that apply to all repairs.
Examine the tire thoroughly, inside and out, to make sure it can be safely repaired. Knowing the parameters of proper tire repair and whether or not the tire can be repaired to run safely are of the utmost importance.
Clean the surface before buffing with a quality chemical cleaner. Use a vacuum when removing rubber dust. Never use an air hose as it only causes dust to float in the air and it can deposit itself back on the cleaned repair area.
Buff an area only slightly larger than the patch to be used. It's ridiculous to buff four inches of liner for a two-inch repair patch as you increase the chance of creating more damage.
Cement causes many repair failures. Keep in mind that solvents and cements evaporate and in doing so they cause cooling. If you cool something in a humid atmosphere, such as a retread shop, moisture will form on the surface.
Allow enough time to let not only the cement dry, but also to allow for the moisture to evaporate. Keep in mind that such moisture may not be visible to the naked eye. Tests have shown a temperature drop of as much as 16 degrees Fahrenheit with just a small amount of cement. It could be greater on a larger patch area.
Our industry should go all out to let the air out of these ``knowledgeable experts'' by disproving their wayward warnings. We have the means to do this with better support for the Tire Retread Information Bureau, our industry's voice.
Meanwhile, retreaders and repair shops should strive for excellence. By using top quality tools, accessories and materials- which also can make the job much easier-retreaders will be using their best method for dispelling myths.