Mystery Tire Leak...
 

So I notice a few weeks after I got my new tires mounted on my new set of wheels, my back left tire had dropped 10 psi in pressure. My first instinct obviously was to pop the wheel off, and inspect the tire for any possible nails, screws, etc. After a friend and I looking it over twice, nothing was found. I re-inflated the tire, and 5 days later, down another 10 psi!


The only thing I could come up with is perhaps the pin inside the valve stem wasn't fully screwed in? Possibility?

could be valve stem, if a three piece wheel the fasteners could be loose..also could just be the tire bead not seating completely...some MPSC and PS2's don't seal completely on some wheels...should have your wheel guy dunk the wheel in a tank of water and see where the air bubbles come from...only one of my four looses pressure but only about 2 pounds a week..the leak is so slow the tank dunk didn't show it....good luck

The naked eye will catch the most obvious nails but it wont catch a small puncture where the nail or penetrating item has fallen out. You should have a tire shop check it unless when you meant friend, you meant tireshop. As for the pin, you can pour water on the valve and check for bubbling.

I had a similar leak that you have- losing 10 psi over a weeks time--- it was a nail I couldnt see but my tire shop found it.

Worse case scenario is that your wheel has a crack or bend in it...or sometimes when tires are mounted, they are not seated correctly as chuck said.

The pin in the valve stem could be the problem, could also be a number of other possibilities...if the valve is an aluminum screw type, it may need to be tightened, also if the wheels are 3pc, it could be the seal did not cure, or got pinched when mounting the tires? If the wheels are chrome, sometimes there is a chemical reaction to the chrome from the soap used to slip the tire on...this reaction causes the chrome to lift and creates small air pockets in where the tire bead sits...to resolve this your tire shop can remove the tire and use a wire brush to clear away the bubbled chrome and then re-mount and balance the tire.

Another to double check, if they used a rubber stem they could have cut it slightly when they installed it.

Most tire shops, and even some gas stations have large tire buckets, drop the entire rim and tire in one of those buckets of water and you may be able to see where the air is bubbling from...if you want to try with the valve to start, just poor some water on it.

I hope this helps.

Jim

you need to spray the tire with water, windex 1 " at a time, when you see the bubbles, that's your leak.

as already stated
check the schrader valve's they might be slightly loose

other than that i'd take a squirt bottle with a little soap and water and slowly go over the tire and rim seams looking for bubbles

if still i didn't find anything then it's time to call the local tire shop and make sure they can handle trying to fix it

Thanks for all the advice guys!

I went over everything with windex, tire, valve, beads. NO LUCK!!!

I'm currently filling my bath tub in hopes of using it as a dunk tank to spot the leak haha.

hilarioushilarious that will work..I like your style

Thanks man, hey, the way I see it is, my house is just some bedrooms and bathrooms attached to my garage anyway.

Back to the issue, after meticulously observing the wheel and tire in my make-shift dunk tank, still, NO LEAKS EVIDENT. I'm beginning to think I'm going crazy.

Is it possible that the seal on the bead only opens up under heavy cornering? If so, perhaps the next step in my troubleshooting will be refill the tire, let it sit for a couple days :( Then check the pressure. Go for a spirited drive, and check again.

Sometimes Tempature can cause the pressure to go up and down...usually only a couple of psi...but this would be the same for all 4 at that point. Are the wheels on the car a 1pc wheel or 3pc wheel?

Exactly, the other 3 corners are staying consistent. The wheels are 3-piece (Cargraphic Racing 19s).

I'll bet the leak is btwn the two halfs of the rim, with the old centerline racing wheels, we used to put a bead of silicone around each inner joint before mounting the tires.

It very well could be a slow leak between the parts...being a 19 using low profile tires it could be possible that when they were mounted that the bead seal on the wheel was pinched or may have just had a thin area that did not seal...and if the leak is that slow putting it in the tub would require letting the rim and tire settle and watch it for an hour to see if a bubble comes up, and it may not because the load is off of it. At this point I would recommend just taking it to the people that did the mounting and balancing and have them dismount the wheel and run an extra bead of silicone...let it cure overnight before mounting it back up...this should solve the problem. Obviously if there is a problem, you need to start somewhere to begin solving it...this would be my recommendation to start.

Jim :)

Any luck with finding the problem? Even though it is not our wheel brand, you can ship your wheel to us and we will disassemble it and assemble it with a clean fresh seal...we have a motorized silicone machine that we use to seal our NUTEK wheels and it provides a even seal. Next we will just have the wheel sit over night so it has time to cure. Most 3pc wheel companies have a torque spec of 22-27ftLBS of torque on the bolts. Since you are here in the US, this might be a simple option since Cargraphic is from Europe...their operation here may only be an importer and unable to properly fix the wheel? We would need to strip the existing seal and then just re-seal it.
Another option would be to see if the importer will exchange the wheel for you...before sending it to us I would recommend contacting them to see if this is an option. If not I am will assist you, you will only need to pay the freight back and forth.

I hope this helps.

Jim

+rep to Nutek; talk about going above and beyond...