Can't find tire leak...

[mwtucker]

I have a tire that is losing air. I have a 5.00 x 5 Aeroclassic Leakguard tube and this is my nose wheel. I filled it to 25 PSI on 6/10/24 and it had leaked down to 7 PSI on 6/14/24. This is after several inflate/leak cycles. The tire is on the bench, not mounted on the aircraft. When I assembled the tube, tire, and wheel halves, I inspected the inner tube visually, used tire talc on the tube and in the tire. Made sure the tube was not pinched between the tire halves. I inflated it to 30 PSI, waited for 24 hours, deflated, and inflated again. I took the inner tube out, inflated it until it felt "tight" to me and submerged it 100% in water. I could find no bubbles. The valve stem cap was off and there were no bubbles from the valve stem or where it joins the inner tube. I squeezed and wiggled the valve stem--no bubbles. I thought that perhaps there was not enough pressure in the tube to be able to see bubbles (i.e. small leak?), so I re-assembled tube, tire and wheel halves and inflated to 30 PSI. I then sprayed soapy water all around both sides of the tire at the bead and also around the valve stem (cap was off). No bubbles. Perhaps the leak is too slow to see any bubbles? I'm not sure what to try next? I've read that some inner tubes leak out through the butyl rubber? I'm at the point where I am considering buying a Michelin Airstop tube? Ka Ching!

Thanks for any suggestions!

Mike

 

[thehagg501]

Have you ruled out anyone messing with ya?

 

[mwtucker]

Yep.

 

[moosepileit]

Look for any surface pore IF it isn't a bad valve seal. Mine was found flat, no leak found first time, changed shrader valve core, leak checked, reinstalled, flat again a few days later.

Patched it, it held while the pricey standard ones were shipped- it was NOT the valve core...

Suggest-

Inflate tube out of tire until firm. Just a few psi, but bigger than when in the tire, but don't get hurt.

Takes a lot to get it to show underwater. Dunk it and squeeze by hand trapping air in near the pore. The leak was like a pinhole, like 10% the size of the pore.

That's how I found mine, safely.

Could not see the pore deflated and it did not leak with only a few psi. I didn't create the leak, I am pretty sure. It was on sidewall and was not a friction scrub.

Even synthetic rubber can have mfg flaws.

 

[Scott Hersha]

I always have a few sets of tire tube shrader valves (available at NAPA, etc). I would deflate the tire, remove the valve, and install a new one (make sure it is really clean), and then re-inflate it. See if it still leaks. This has worked for me more than once.

 

[BH1166]

I have a tire that is losing air. I have a 5.00 x 5 Aeroclassic Leakguard tube and this is my nose wheel. I filled it to 25 PSI on 6/10/24 and it had leaked down to 7 PSI on 6/14/24. This is after several inflate/leak cycles. The tire is on the bench, not mounted on the aircraft. When I assembled the tube, tire, and wheel halves, I inspected the inner tube visually, used tire talc on the tube and in the tire. Made sure the tube was not pinched between the tire halves. I inflated it to 30 PSI, waited for 24 hours, deflated, and inflated again. I took the inner tube out, inflated it until it felt "tight" to me and submerged it 100% in water. I could find no bubbles. The valve stem cap was off and there were no bubbles from the valve stem or where it joins the inner tube. I squeezed and wiggled the valve stem--no bubbles. I thought that perhaps there was not enough pressure in the tube to be able to see bubbles (i.e. small leak?), so I re-assembled tube, tire and wheel halves and inflated to 30 PSI. I then sprayed soapy water all around both sides of the tire at the bead and also around the valve stem (cap was off). No bubbles. Perhaps the leak is too slow to see any bubbles? I'm not sure what to try next? I've read that some inner tubes leak out through the butyl rubber? I'm at the point where I am considering buying a Michelin Airstop tube? Ka Ching!

Thanks for any suggestions!

Mike

5:00-5 on an RV nose….. is this a RV10? Since the 50’s leaking tubes produce bubbles under water on my bikes. Poor light, poor vision, impatient…dunno.

 

[Aden Rich]

I would try SNOOP as it's meant to test for small leaks. Water is a lot more viscous than SNOOP and there you can find leaks when you cannot locate it with water.

 

[Walt]

Install a new Michelin Airstop and move on.
I would never patch a tube unless it was an emergency fix.

 

[wirejock]

5 Years as a truck tire mechanic.
It can be tough to find a leak like that.
Inflate the tube and submerge. Grab a beer and watch for the trail of bubbles. Or
A few drops of dawn or some kids bubbles mixed with water in a spray bottle. Spray and wipe so there's a film. A leak will show as a trail of bubbles. I found a tiny hole in my thermorest mattress that way. Fixed it with a patch and proseal!
Or
Replace the tube.

 

[mwtucker]

Look for any surface pore IF it isn't a bad valve seal. Mine was found flat, no leak found first time, changed shrader valve core, leak checked, reinstalled, flat again a few days later.

Patched it, it held while the pricey standard ones were shipped- it was NOT the valve core...

Suggest-

Inflate tube out of tire until firm. Just a few psi, but bigger than when in the tire, but don't get hurt.

Takes a lot to get it to show underwater. Dunk it and squeeze by hand trapping air in near the pore. The leak was like a pinhole, like 10% the size of the pore.

That's how I found mine, safely.

Could not see the pore deflated and it did not leak with only a few psi. I didn't create the leak, I am pretty sure. It was on sidewall and was not a friction scrub.

Even synthetic rubber can have mfg flaws.

Thanks moosepileit!

 

[mwtucker]

I always have a few sets of tire tube shrader valves (available at NAPA, etc). I would deflate the tire, remove the valve, and install a new one (make sure it is really clean), and then re-inflate it. See if it still leaks. This has worked for me more than once.

Thanks Scott.

 

[mwtucker]

I have a tire that is losing air. I have a 5.00 x 5 Aeroclassic Leakguard tube and this is my nose wheel. I filled it to 25 PSI on 6/10/24 and it had leaked down to 7 PSI on 6/14/24. This is after several inflate/leak cycles. The tire is on the bench, not mounted on the aircraft. When I assembled the tube, tire, and wheel halves, I inspected the inner tube visually, used tire talc on the tube and in the tire. Made sure the tube was not pinched between the tire halves. I inflated it to 30 PSI, waited for 24 hours, deflated, and inflated again. I took the inner tube out, inflated it until it felt "tight" to me and submerged it 100% in water. I could find no bubbles. The valve stem cap was off and there were no bubbles from the valve stem or where it joins the inner tube. I squeezed and wiggled the valve stem--no bubbles. I thought that perhaps there was not enough pressure in the tube to be able to see bubbles (i.e. small leak?), so I re-assembled tube, tire and wheel halves and inflated to 30 PSI. I then sprayed soapy water all around both sides of the tire at the bead and also around the valve stem (cap was off). No bubbles. Perhaps the leak is too slow to see any bubbles? I'm not sure what to try next? I've read that some inner tubes leak out through the butyl rubber? I'm at the point where I am considering buying a Michelin Airstop tube? Ka Ching!

Thanks for any suggestions!

Mike

Thanks all, for your replies!
Mike