About a week ago, I noticed the passenger rear tire was going low. I searched for a nail or any cause, found none. Filled it, took about a week to go down again. Took it to the tire dealer, he found the leak was coming from the rim bead. When they wet down the wheel with soapy water, you could see bubbles in two places around the rim / tire. They dismounted the tire, found the rim had some corrosion where the tire meets the rim. He lightly sanded the area smooth, I was a bit worried as he did this, he said this happen often. Now a few days later, seems to have taken care of the problem. I've never heard of this happening, searched the web, do see there are actually documented cases where this has happened.
I've seen it happen when a car sits for a period with a flat tire or the rim is left lying around without a tire on it. Sometimes they will leak around the bead because the bead of the tire is bad, too. On one occasion I've seen an alloy rim leak through the main body of the rim, due to a bubble in the casting. An American Racing slotted dish wheel I had on my kit car.
Leaking on the tire bead is one if not the most common issue. It happens on aluminum and steel wheels both. While it is more common with some weather conditions and or wheel and tire combo's it is just one of those things that happens.
Years ago we used to take a light bead of tranny fluid to soften the rubber and lube the wheel and generally it would fit it.
I can remember back in the 80's the Pontiac dealer would bring us tires to dismount on new Pontiac cars. The cast wheels once in a while would be porous and leak air though the casting. They would epoxy the wheel where the leak was and remount and balance the tire and wheel. That was the fix. It was much like JB Weld.
I worked at a gas station when I was in high school and collage and saw it all when it comes to tires.
There is also a rubber cement like material they can paint on the rim to help it seal too. Often if the steel rim was rusted I would hammer off the lose material. The Aluminum sanding or a light sanding disk can clean it up. Odds are it will return if it is not cleaned and sealed properly. Most aluminum wheels are resistant but it still can happen.
Originally posted by hyperv6: There is also a rubber cement like material they can paint on the rim to help it seal too. Often if the steel rim was rusted I would hammer off the lose material. The Aluminum sanding or a light sanding disk can clean it up. Odds are it will return if it is not cleaned and sealed properly. Most aluminum wheels are resistant but it still can happen.
Bead sealer goes on the bead of tire. I would use this because seals out water/crap that's wick into the bead causing the problem, more so after wire bush that removes rust, paint, and whatever on the rim.
I worked in a tire shop for 5 years and can say that is is indeed a VERY common thing. We had air die grinders beside every tire machine with wire wheels on them. Every single wheel, aluminum or steel, got brushed before the tire was put back on the wheel. On particularly bad wheels, you'd brush them, then paint them with bead sealer. Then again, I am in PA, where salt and calcium chloride is sprayed on the roads almost religiously from October to April, with or without snow it seems.
We used it on the rim or tire it just depended on what was easiest. It all ended up in the right place.
Also breaking the bead most times the material we used was not a big problem. The only beads that were a problem often were Michelin. They would be a tight fit with a slight undersize. They would take more air to seat ad more power to break down. Often they rusted like any other wheel.
This was back in the 80's and before many of the better tire machines we have today. I used to have to improvise on the machines we had. We used to do a lot of work for the major tire companies and often we saw larger wheels and wiser tires before anyone else. I remember mounting the first Comp TA radials back in the late 70's. We though 16" 50 series were crazy sized tires.
We did advertising so we did upgrade machines later to match the larger tires and the much more expensive wheels. They would give us wheels back in the 80's that were $650 to $2,000 and no margin for error. Also we started getting Goodyear and BFG race tires for photo shoots. I remember the large F1 tires from Goodyear. Even the large rear F1 tires mounted were something like 8 pounds even on the wheel. they were so light.
[This message has been edited by hyperv6 (edited 01-24-2017).]