Flat Tire Several Options to Fix a Flat Tire on Your Car or Truck

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A flat tire halted our travel plans for the day, and a quick visit to the garage revealed a rather large nail was the cause of the flat...

We Discovered that We Had a Flat Tire

We started out on a little commute yesterday and discovered that the right-front tire was completely flat. It had gone down during the night. Our little travel plans came to an abrupt halt. There would be no holiday travel adventure today.

Had the flat tire occurred on the road or away from home, we could have easily installed the spare tire from the trunk. This is a ‘mini tire’ sometimes disdainfully called a ‘donut.’ It is intended to save space in the trunk by being about 75% smaller than the standard-sized tire for the model vehicle.

It is also considered to be an ‘emergency use’ tire, not intended for extended use or even for full highway speeds. It will get you home or to the garage. That is about the extent of their usefulness.

Most people after having used the ‘donut tire’ once discard it in lieu of a full-sized spare for the next time, such is the disdain for these ‘mini-tires.’

An option for a flat tire instead of installing the mini donut tire is a product called “Fix-A-Flat.” It is a foamy liquid surfactant that is pumped into the flat tire via the filler nipple on the can. This surfactant suds has the ability to seal most minor punctures in the tread of a flat tire. You are required then to drive the car for a minimum of 15-minutes to evenly distribute the foam inside of the tire. Fix-a-flat and similar products are completely ineffective on sidewall punctures however.

The sudsy properties of the injected foam product rolls around inside the tire, flattening out and sealing the minor leak. It will not effectively seal a hole that has a physical object in it (nail, wire, etc.) and the nail or wire will continue to shift around during normal driving, exacerbating the existing puncture site. It is intended mostly for puncture and withdraw incidents; cases whereby the offending puncture device does not stay with the tire. Small shards of broken glass may even enter the interior of the tire and remain there until the next time the tire is replaced.

Mechanics as a rule don’t like the use of ‘Fix-A-Flat’ products. This is because the propellant gases that the Fix-A-Flat product uses are flammable, there is potential an explosion. Steel belted radial tires have steel wires that run radially (in the direction of the tire when rolling) inside of the tire’s structure and when the mechanic is using metal tools to disassemble the tire, a simple spark could ignite the pressurized explosive gases.

In short; if you have ever used any ‘Fix-A-Flat’ or other tire-inflating product and your mechanic will be working on the tire, DO TELL THEM about this in advance.

I removed the flat tire from our car in our parking garage and using my son’s little red wagon, brought it to my favorite mechanic. I had already spotted the offending culprit in the tire's tread; it was a nail or other shiny metallic object. It was clearly visible just barely sticking out of the tread.

I felt some relief upon seeing this for a nail puncture is more likely to be fixable than a glass puncture because the nail hole will be smaller and more uniform in shape and size. Also, that the hole was in the ‘tread’ part of the tire which bodes well for repair. Any hole in the sidewall of any tire is not repairable and the tire is a complete loss.

It is a notable distinction between a puncture in the tread surface versus a puncture in the sidewall. The sidewalls of tire are and need to be flexible during use. Sidewalls are much thinner than the tread and would not hold a plug anyway. Any ‘patch’ or ‘plug’ would very quickly fail under even moderately normal use, perhaps with catastrophic results.

The mechanic inflated the tire to verify the findings. As he was inspecting the tire, we could hear air leaking out of the suspected spot. Using pliers he deftly extracted the offending piece of hardware and it was revealed to be a rather large nail.

The Actual Nail that was Removed from the Tire

(image by author) (not to scale)

Using a small ‘rat-tail file’ of the plug-repair kit, he inserted this into the hole to ‘rough-up’ and clean the puncture in preparation for a rubber plug and adhesive. This is where if 'Fix-a-flat' has been used, the rat-tail file rubbing against a steel belt wire could trigger an explosion.

Next, the sealing plug is applied. The rubber plug is like a big fat shoelace several inches long, threaded through the eye-hole of a heavy-gauge needle-like device with a T-handle on the end. The rubber plug is coated all around with this rubber adhesive and forcibly inserted into the puncture site and withdrawn about half-way. This seals effectively seals with hole as the rubber cement adheres. The rubber shoelace tail that protrudes from the tire is then snipped-off even with the tread surfaces.

This type of repair is quite sound and reliable. Because the ‘rubber plug’ is in fact made of the same material as the tire it will behave just like the tire. It wears evenly with the tread from that point on.

This type of repair is quick (it only takes about 5-10 minutes for the mechanic to perform) and it is cheap (about $10.00.) If you had this flat tire on your car and the tire was not completely flat, the mechanic could quite possibly repair the tire while still mounted on your car. He would just run it up on the hoist to have a better look at it and repair the tire as described in~situ. In all liklihood however, your flat will not occur in the mechanic's parkinglot so you are expected to bring the tire in unmounted from the vehicle.

Steel Belted Radials have Steel Wires Inside the Tire

a steel belted tire that endure a fire, showing exposed steel wires (belts)

(image source) (although this steel-belted tire endured a car fire, it clearly shows the steel-wires that were mentioned earlier)

Driving upon a flat tire for any great distance (more than a few hundred feet?) will break the steel wires in the radial tread and these in turn will rip and shred the inside of the tire, rendering it ruined.

Driving upon a flat tire for any extended distance, evenly slowly, will destroy any possibility of repairing the tire.

1 comment

Sotiris Kara
Posted on Feb 16, 2010