Blow-outs

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After the thrill of motoring a ’36 P.A. at 70 MPH,I had the sobering thought,”what if a tire had blown?””.Has anyone had a blowout

at highway speed with a ’30’s P.A.Which tire went and how did it effect your control?

A. Costa”

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I was driving George Tebay’s Silver Arrow through the Mojave Desert last summer on the way back to northern Callifornia after the Meet in Temecula.

The 105* heat, and the poor quality [thin] new inner tubes didn’t get along.. I had the right rear tire go flat in about 100 yards.. Not an explosive tire failure, but quite quick.

The rear of the car was swaying around a lot, the thankfully the roadway was quite flat, and there was a turnoff for a side road at just the right spot.. So I pulled over, not that I had any choice, and got well off the road..

I had the spare on the car and back on the road in about 12 minutes.. I moved fast ’cause there was no shade, and I felt like I was under a heat lamp.

Our Pierce Arrows are quite heavy, and the tires are barely adequate for the weight they carry.. you must keep the tires well inflated to keep the swaying to a minimum, and to provide some safety if one tire blows. You will need all the control you can get from the remaining [hopefully well inflated] tire.

If I had been on a curve, or with a stiff crosswind, then the car would have been a bit of a handfull..

So, take good care of your tires keep them inflated, or even over inflated.. I run my 750-17’s on my 836 at 45 psi.. an ‘over inflated’ tire runs cooler and offers more control of a heavy car.

By the way,, George had another tube failure the next day, with the same results.. a quick deflation, a bit of swaying, and a convenient ramp to pull well of the road.. I was just behind him.. this time I mangage the tire swap in about 10 minutes.. I was starting to feel like a member of a Pit-Crew.

All the new tubes were changed to heavy duty truck tubes.

Greg Long

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I agree with what Greg said. I lost a right rear tire on my 31 Cadillac at 65 MPH on a race track in a sweeping left hand turn. The failure was an explosive type, the tire tore off the rear fender 100% and 2/3 of the running board. I thought the car was going to roll over…… but I managed to keep it somewhat under control. Damage was about 20% of the value of the car. Now I replace tubes every 10 years. (In the process of doing it to all my cars right now, and I am about 25% done.) The fact of the matter is almost all of us drive faster than the car can safely handle a blowout. Good tires, tubes, and maintenance are the best prevention. And now a short note on old tires. Most of the club members have seen my 33 LaBaron at the meets the past ten years. When it was fresh out of the barn I ran it for several weeks before I put new tires on it. When I went to change out the first tire and I had let the air out of it I stood on the sidewall to see if the bead would brake loose. MY FOOT WENT THROUGH THE SIDEWALL!!!!!!!! Not a small hole or tear but the entire size of my shoe went right through. I was very disturbed, and will never forget John Cislak laughing his a** off at me. We had been running the car 60 MPH for 45 minutes on a hot day just a few days before! All the tires were in a similar condition and they showed no signs of age cracking or separation. Play it safe and always use good judgment when it comes to tires, tubes, and rims.

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Ed, I’m currious, do you remember the make and compostion of the old tires you describe? Do you remember if the cord or ‘plys’ in the tires were of man-made material like nylon or polyester, or was the tire old enough to have natural cotton cord ?

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An additional note about tubes. When George and I had the first tire dismantled for a tube replacement, we were mystified, there was a small tear on the inner part of the tube, where it would seem obvious that a sharp edge on the wheel or a tire bead caused damage to the tube.

But there was NOTHING, not ANYTHING even remotely sharp or potentially damage causing on the rim or the tire. We installed the old tube over the naked wheel, and closely inspected every surface for a culprit. Nothing was found..

BUT we noticed that the tube fit over the wheel quite loosly. The tube would have filled the tire, but been loose down near the bead and especially in the drop center.. So as this original tube was inflated, it expanded to fill the tire first, but there would have be a large area in the drop-center of the wheel that would not get filled with the innertube untill it was fully inflated..

So the inner tube was being stretched very thin in the drop-center part of the wheel, and this is where the tube had developed a small tear.. We decided that the thin tube material was stretched too far when inflated into the drop center.

We checked the tube size, it was new so the inked size markings were still very clear and easy to read, the size was correct for the tire.. Hmmm.

What we did, was to use a 16.5″ truck tire tube on the 17″ rim. This meant that the tube fit tighter down in the drop-center, and more of the tube expansion when inflated would be in the tire, where there was a lot more area to expand, minimizing localized stretched-too-thin spots down into the drop-center.

So if you can get involved with the tire changing, or if you are doing it yourself, consider what is happening when you inflate your tire, use plenty of talc to facilitate the tube sliding and becoming wrinkle-free as it inflates.

I use a method taught to me by my father, inflate the tube, then fully deflate, put a ‘T’ valve stem retainer on the valve stem, then take the deflated tire and wheel and try to play basket ball with it,, bounce it on the ground all the way around the tire, this jarring, flexing with a deflated [loose] tube will allow the tube to center itself, hopefully taking out any wrinkles in the positioning of the tube in the tire,, this is where plenty of talc in the tire helps lubricate the tube. Reinflate slowly so the tube can stretch evenly.

Hope all the above makes sense and is helpful

Greg Long

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Greg has covered this very well, but let me add this: Before installing the new tires and the 17″ tubes, I had spent the better part of a day dressing each wheel’s inside portion with very fine sandpaper to preclude any sharp or semi-sharp edges, and ensuring that the bands (which prevent the tube from rubbing where the steel artillery spokes are attached) were in good condition. I also used Metal-Prep on the bare steel, followed by a very thin coat of rust-preventing primer, then let the wheels dry for a couple of days.

The two 17″ tubes failed on the bonded seams. After installing the 16.5″ radial truck tubes, which are considerably heavier/thicker than the the 17″ tubes furnished with the tires, I’ve had no further problems.

George

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This info is most helpful, thank you all for putting this string of posts together.

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I know that tire flaps(a rubber donut that fits between the wheel

and inner tube)are a necessity on earlier autos.Are they available and

commonly used on classic cars?Flaps and gobs of tire talc would go a long

way to prevent inner tube failure!A 5600 lb. car might exert some negative

influence on inner tube flexing(whatever that is).

Tony Costa

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Yes, flaps are available from all the vintage tire retailers, like Coker, Universal etc. Do a google search for antique tire and you will find several retailers.

Greg Long

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