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View Full Version : A Lesson Learned?


del
04-10-2017, 10:06 PM
Around 5 years ago when we moved to this neighborhood, I quickly became acquainted with the guys who ran the local repair shop, two brothers who had been at the same location since the early '70's. The shop, let's call it Shop"A", became the go-to place for our modern vehicles, and I began to take the T-Bird there for annual inspections. The gentlemen running Shop A were always helpful and were happy to recommend other shops, if a job was not in their wheelhouse. Which was the case about 2 years ago when I got radial tires (Coker 215/75R14 2 1/2" WWW) and wanted to get the front end aligned. The guys at Shop A recommended Shop B as the place to go to get the alignment done, so even though further away, I had Shop B mount the radials on my stock 14" steel wheels and do the alignment. All was right with the world! Meanwhile, the brothers at Shop A retired and sold to new ownership. Since Shop A still was close by, we stuck with the new owners & staff for routine maintenance on our modern cars, and things were fine.

Fast forward to a couple of weeks ago. I checked out 7 local bone yards looking for 14" wheels that will work with my upcoming disk brake conversion. I was batting zero for six, but scored these off a '90 something Ranger at the lucky 7th yard. This morning, I dropped the T-Bird at Shop A to have them mount my tires on the new wheels. When I dropped it off I mentioned that I didn't know if the lugs nuts were going to work or not, and I didn't have centers yet. Turns out the lugs didn't work, so @$5 per...oh well it's only money. Couple hours later comes the panicked phone call.

"Who mounted these tires for you? The beads are all messed up! We got one of them so seal alright, but this second one is really bad and won't seal. We decided to stop and have you take a look." I say,"They were mounted by Shop B a couple of years ago. Never had any problems...See you in a few." I drive over to Shop A and have a look. The bead on the tire is totally shot, front and back. The young mechanic doing the job is concerned that ALL four tires might be messed up, since the first two that he broke down were! So, I take the two tires that had not yet been dismounted from the wheels, along with the roached unmounted tire, over to Shop B.

The owner there remembered my car from two years ago and doing the job. I explained the situation, in that Shop A was implying that Shop B was somehow responsible for my tires being messed up, due to improper mounting. I explaining that I wanted him to dismount these two remaining tires so we could see if there was any damage. He initially asked if it could wait until tomorrow to dismount the tires, but when I said that my car was up on the lift at Shop A, he agreed to immediately dismount the two remaining tires to examine them for damage. Lo and behold, the beads were flawless! His mechanic was also kind enough to show me that, contrary to most modern wheels, disengaging the tire from these rims has to start ON THE BACK SIDE! This is apparently due to the stiffer construction on the front side of the wheel, which doesn't allow enough flex for that first dismounting move. Who knew? I sure didn't. Shop B charged me nothing for disrupting his afternoon workflow with an inaccurate accusation from a competing shop. Something to think about...

So, back to Shop A...with the now dismounted tires and a very clear picture of where and how my tires got damaged. The young Shop A mechanic greeted me with "How did it go?" I said, "Well I got good news and bad news. The good news is that the beads on the two tires that you did not touch were, in fact, flawless. The bad news is that if you started the removal process from the front side instead of the back side, then YOU damaged the beads, not the previous installer." Crickets from the young mechanic, and at this point the owner of Shop A came over and I explained the situation again to him. He stated that he had never heard of such a thing in 35 years of mounting tires, but his young mechanic did acknowledge that he started the dismount process with the front side up!

So, as result Shop A is buying me two new tires. They will not be touching the T-Bird again, and I may need to reconsider them as my go-to for the modern vehicles.

Lot's of lessons for everybody on this one.

Cheers!

Dan Leavens
04-11-2017, 09:14 AM
Don thanks for sharing this with us and proves a point. Make sure you have confidence in your repair shop AND employees

simplyconnected
04-11-2017, 09:55 AM
Don, it's a good story with a good lesson but not for the consumer. The guy doing the work, you know, the one being PAID, should have enough experience and knowledge to perform his job. A set of four new OEM replacement Michelin tires mounted on the family Escape costs about $800. This is serious bucks.

Personally, I have never seen wheels that are different diameters on each side. The wheels we use at Ford are symmetrical.

Our mounting procedure is fast and automated. We spritz soapy water on the tire then drop it on a face UP rim. A set of rollers quickly tucks both beads over the top face of the rim then we inflate from the bead, not the stem.

Remember, an assembly plant produces about 1,000 cars per two-shift day, so that's 5,000 tires on 5,000 rims. The same machine mounts different size tires to steel and alloy rims. The mounting sequence is violent and if soap runs out, sometimes we tear tires. On average maybe two tires per shift are torn. Four out of 5,000 isn't cause for concern.

So, when your bare wheel is rolling on the floor, does it travel in an arc? (I've never seen such a thing.) It would have to if one bead was taller than the other side. - Dave

Yellowbird
04-11-2017, 09:58 AM
I had the same thing happen to me. Tire shop close by that I've used many times before (but not on my '58) started removing tires to be put on new rims. After destroying 2 of the tires at the bead area I had them stop.

I went to another shop that I had use close to work. The person looked at them and said the same thing. You have to remove them from the back side not the top.

I glad you are getting your tires replaced. My shop would not take responsibility. So...I don't use them any longer and I no longer recommend them!

del
04-11-2017, 02:53 PM
Hi Dave, It is not the diameter of the wheels that was the issue, rather it has to do with the thickness / stiffness of the steel leading up to the edge of the rim on front and back. The way it was explained to me is that the back side of the rim provides some flex that the front side doesn't to assist in removal.

Don, it's a good story with a good lesson but not for the consumer. The guy doing the work, you know, the one being PAID, should have enough experience and knowledge to perform his job. A set of four new OEM replacement Michelin tires mounted on the family Escape costs about $800. This is serious bucks.

Personally, I have never seen wheels that are different diameters on each side. The wheels we use at Ford are symmetrical.

Our mounting procedure is fast and automated. We spritz soapy water on the tire then drop it on a face UP rim. A set of rollers quickly tucks both beads over the top face of the rim then we inflate from the bead, not the stem.

Remember, an assembly plant produces about 1,000 cars per two-shift day, so that's 5,000 tires on 5,000 rims. The same machine mounts different size tires to steel and alloy rims. The mounting sequence is violent and if soap runs out, sometimes we tear tires. On average maybe two tires per shift are torn. Four out of 5,000 isn't cause for concern.

So, when your bare wheel is rolling on the floor, does it travel in an arc? (I've never seen such a thing.) It would have to if one bead was taller than the other side. - Dave

partsetal
04-11-2017, 08:52 PM
Hopefully I can clarify the problem w/Squarebird rims. The beads of tires are designed to fit behind the wheel rim. The bead in the tire is constructed of steel wires that do not stretch or change in length. To mount the bead behind the rim, the entire tire is cocked so that one portion of the bead rests in the gutter of the wheel (this is the deep depression around the wheel, visible when the tire is removed) A tool is used to roll the portion of the tire that in not in the gutter over the edge of the rim. The bead has not changed in diameter, but by using the gutter and angling the tire there is sufficient clearance to fit the diameter of the bead over the rim.
In removing the tire, one must first break the beads loose from the rims of the wheel and locate one bead into the gutter. With one bead in the gutter, a tool is used to pry one portion of the bead up and over the rim and repeat the process around the tire. A tire machine does this with ease until all of the bead is above the rim. The other bead is moved into the gutter and the process repeated until the tire is free of the wheel. The wheel gutter is sometimes located in the center of the wheel, and on some wheels it is near the front. The squarebird wheel has the gutter near the back of the wheel. For this reason the tire is to be mounted/removed from the back of the wheel. The gutter is too far from the front of the wheel to be angled and fit over the rim. Modern tire machines are sophisticated tools designed to deal with alloy, wheels low profile tires, specialty tires and the like. They are very powerful and will damage the bead as happened in Del's situation.
Carl

simplyconnected
04-11-2017, 11:05 PM
Carl, that explanation was excellent. Modern rims, (especially 14") have plenty of clearance for disk brake calipers. That means the 'gutter' must be toward the front or center of the rim, NOT in the back. You can see the caliper clearance 'hump' on this 14" steel wheel:

http://squarebirds.org/Brakes/DiskBrakeConversion/HowardsWheels/DSCN5046.jpg

Notice the stem hole on the lower left (front side) as Howard Prout measures back spacing.
If 'tire changers' are tearing tires, they are simply not busting the tire down to put the bead in that 'gutter' before rolling the tire bead over the rim.

Check out the contour of your alloy rims as they have more 'gutter' in the center and front:
http://www.squarebirds.org/vbulletin/attachment.php?attachmentid=13885&stc=1&d=1491871912
- Dave

del
04-15-2017, 10:17 AM
The replacement tires arrived yesterday and are being mounted this morning, assuming that they decompress enough from the shipping wrap.

Agree x2 Great Explanation Thanks Carl! The gutter is the area of the wheel that the mechanic was pointing to when he described it as thinner, so now things make more sense. I had never watched closely enough or talked to anyone about the technique, and I suppose that a mechanic with experience on a fully drum brake vehicle is getting to be a rarity.