Tire leaks without actaully leaking - help.

One of my tire deflates from 32 to 9-psi mysteriously every two
weeks. The other three tires are fine, they hold charge pretty well.
They're all the same brand. The tire in question have good threads
and never been punctured, other than being aged from the sun.

I remove the wheel from the car and inflate it to 40-psi. I
submerge the tire into a pool of water. No air bubbles! I pump it
to 44-psi. No air bubbles! I install it onto the car and it begins its
slow leak. I have another Honda that does this. I just give up and
buy a new tire. Would you have pump it to 50-psi? How would
you have done it differently?

TIA, Tibur Honda Accord `92 130K, Toyota Tercel 140K mi.

 

This used to happen on my 89 Prelude.
The tyre wasn't sealed to the rim properly.
The gap only let out air when the weight of
the car was compressing the wheel and
tyre, so the leak couldn't be replicated in
a workshop, just like you describe. The
problem was solved by refitting the tyre.

HTH,
Al

 

This used to happen on my 89 Prelude.
The tyre wasn't sealed to the rim properly.
The gap only let out air when the weight of
the car was compressing the wheel and
tyre, so the leak couldn't be replicated in
a workshop, just like you describe. The
problem was solved by refitting the tyre.

HTH,
Al

 

Use dish soap in water and a rag and wipe it down good. Use enough soap that
it will foam up good. Even a slow leak will cause bubbles to grow and they
will be easy to see. Wipe the soapy water everywhere (include the bead area as
other poster said, the rim itself, around the valve stem and the valve stem
itself). You will probably find something stuck in the tread you that closed
over or a leak at the bead. Could be the valve stem or even a bad casting if
these are Aluminum rims (heard of this but never seen it).

 

Use dish soap in water and a rag and wipe it down good. Use enough soap that
it will foam up good. Even a slow leak will cause bubbles to grow and they
will be easy to see. Wipe the soapy water everywhere (include the bead area as
other poster said, the rim itself, around the valve stem and the valve stem
itself). You will probably find something stuck in the tread you that closed
over or a leak at the bead. Could be the valve stem or even a bad casting if
these are Aluminum rims (heard of this but never seen it).

 

I've seen this due to two factors:
1) A puncture
2) Rim leak.

1) Sometimes the puncture is inflicted just so, so that the puncture needs
to be close to the ground, in the distorted portion of the tread that is
close to where the tread actually touches the road. If the puncture lies in
that flexed portion, the hole is forced open, causing a leak. Next time you
stop, if the puncture happens to be in a portion of the tire AWAY from the
road, there is no distortion, and therefore no leak.

2) Same thing as above can happen with a rim leak. Rim leaks can also be
affected by temperature. Colder day, lower pressure, more flexing, more
leak.

Solutions:
1) Remove tire from rim. Inspect INTERIOR for puncture. Repair if found.
2) Remove tire from rim. Sand off rust on wheel/tire mounting surface.
Clean flakes of rust off tire bead. Apply tire sealant to bead of tire or
rim. Reseat on rim.

 

I've seen this due to two factors:
1) A puncture
2) Rim leak.

1) Sometimes the puncture is inflicted just so, so that the puncture needs
to be close to the ground, in the distorted portion of the tread that is
close to where the tread actually touches the road. If the puncture lies in
that flexed portion, the hole is forced open, causing a leak. Next time you
stop, if the puncture happens to be in a portion of the tire AWAY from the
road, there is no distortion, and therefore no leak.

2) Same thing as above can happen with a rim leak. Rim leaks can also be
affected by temperature. Colder day, lower pressure, more flexing, more
leak.

Solutions:
1) Remove tire from rim. Inspect INTERIOR for puncture. Repair if found.
2) Remove tire from rim. Sand off rust on wheel/tire mounting surface.
Clean flakes of rust off tire bead. Apply tire sealant to bead of tire or
rim. Reseat on rim.

 

That is a rim leak you are describing.

Try testing it in water with only 10 or 15 psi in it. Adding all that
air seals the leak up. Then putting the vehicle weight back on it works
the leak loose again.

Same thing just happened to our Cherokee with it's aluminum rims. I
took the tire into the shop and they said it isn't leaking. I had to
argue with the fool to get him to take my money for a rim leak fix he
figured I didn't need.

It hasn't leaked since.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

 

That is a rim leak you are describing.

Try testing it in water with only 10 or 15 psi in it. Adding all that
air seals the leak up. Then putting the vehicle weight back on it works
the leak loose again.

Same thing just happened to our Cherokee with it's aluminum rims. I
took the tire into the shop and they said it isn't leaking. I had to
argue with the fool to get him to take my money for a rim leak fix he
figured I didn't need.

It hasn't leaked since.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

 

Tibur Waltson wrote in rec.autos.tech

One of the common areas to leak is the valve stem. Leave the tire
on the car, inflate to normal pressure. Then put a little bit of
spit in your mouth and wipe it over the head of the valve stem. If
a bubble forms, you will need to tighten the stem.
If you don't see one, take the tire to a tire shop and have them
check it. They will know how to check for leaks properly, and they
will have a tire tank to check it in. When I worked in a gas station,
back in the days when they were truly full service, I checked many tires,
and found some that were leaking at the stem, or at the bead, even though
the tire itself looked good. And those leaks were hard to see without
the tank.

--
Dick #1349
Damn it . . . Don't you dare ask God to help me.
To her housekeeper, who had begun to pray aloud.
~~ Joan Crawford, actress, d. May 10, 1977
Home Page: dickcr.iwarp.com
email:

 

Tibur Waltson wrote in rec.autos.tech

One of the common areas to leak is the valve stem. Leave the tire
on the car, inflate to normal pressure. Then put a little bit of
spit in your mouth and wipe it over the head of the valve stem. If
a bubble forms, you will need to tighten the stem.
If you don't see one, take the tire to a tire shop and have them
check it. They will know how to check for leaks properly, and they
will have a tire tank to check it in. When I worked in a gas station,
back in the days when they were truly full service, I checked many tires,
and found some that were leaking at the stem, or at the bead, even though
the tire itself looked good. And those leaks were hard to see without
the tank.

--
Dick #1349
Damn it . . . Don't you dare ask God to help me.
To her housekeeper, who had begun to pray aloud.
~~ Joan Crawford, actress, d. May 10, 1977
Home Page: dickcr.iwarp.com
email:

 

Had the same problem on my 96 ex Accord 5sp coupe. Leak was impossible to
find, but it lost air (10 lbs every 2 weeks). Took the car to NTW, they said
it was a known problem with the OEM Michelins and put some sealant goop on
the alloy rims. This helped, losses went down to 5 lbs every 2 months. When
I replaced the OEMs with Dunlop SP40s the problem went away permenantly,
they don't lose even 1 lb in 3 months. Also, car rides and handles better
though the tires are a bit noiser at slow speed (Under 30mph).

 

Had the same problem on my 96 ex Accord 5sp coupe. Leak was impossible to
find, but it lost air (10 lbs every 2 weeks). Took the car to NTW, they said
it was a known problem with the OEM Michelins and put some sealant goop on
the alloy rims. This helped, losses went down to 5 lbs every 2 months. When
I replaced the OEMs with Dunlop SP40s the problem went away permenantly,
they don't lose even 1 lb in 3 months. Also, car rides and handles better
though the tires are a bit noiser at slow speed (Under 30mph).

 

the tire shop i go to puts 50 lbs of air in the tire so when they try to
find the leak the air will come out pretty easy.......

 

the tire shop i go to puts 50 lbs of air in the tire so when they try to
find the leak the air will come out pretty easy.......

 

Tibur,
Others have suggested valve stem, poor bead seal, and a hidden puncture. All
are good possibilities but allow me to suggest still another. Have you ever
run the tire with low air pressure (such as the first time it happened)? If
so, you may have destroyed the inner liner of the tire. All tires are made
from synthetic rubber compounds with different formulae but all have one
characteristic in common - they are all porus. Air will leak out through the
rubber of the tire because it is not airtight. This is over come by spraying
a thin film of hypalon based compound (usually) inside the tire. This
compound seals the tire. The only problem with this compound is that it is
not very flexible. Under severe flex situation, such as running the tire
seriously underinflated, will cause that lining to break up into small
pieces, detach itself from the inner walls of the tire, and the tire will
leak. Suggestion: dismount the tire and see if it is full of rubber debris.
If so, that is the problem and the only solution is to replace the tire.
Replace the valve stem and reseal the bead when doing this (if the inside of
the tire is clean) and your problem should be solved...

Dave D

 

Tibur,
Others have suggested valve stem, poor bead seal, and a hidden puncture. All
are good possibilities but allow me to suggest still another. Have you ever
run the tire with low air pressure (such as the first time it happened)? If
so, you may have destroyed the inner liner of the tire. All tires are made
from synthetic rubber compounds with different formulae but all have one
characteristic in common - they are all porus. Air will leak out through the
rubber of the tire because it is not airtight. This is over come by spraying
a thin film of hypalon based compound (usually) inside the tire. This
compound seals the tire. The only problem with this compound is that it is
not very flexible. Under severe flex situation, such as running the tire
seriously underinflated, will cause that lining to break up into small
pieces, detach itself from the inner walls of the tire, and the tire will
leak. Suggestion: dismount the tire and see if it is full of rubber debris.
If so, that is the problem and the only solution is to replace the tire.
Replace the valve stem and reseal the bead when doing this (if the inside of
the tire is clean) and your problem should be solved...

Dave D

 

But not if the leak is because the tyre isn't sealed to
the rim properly, and all that pressure is actually
holding the tyre securely against the rim...

Al

 

But not if the leak is because the tyre isn't sealed to
the rim properly, and all that pressure is actually
holding the tyre securely against the rim...

Al

 

Then they are fools.

If you have a rim leak, high pressure will seal it up great.

Mine would go flat overnight. Took it to shop. Shop pumped it up hard
and no bubbles in water tank. Shop left it overnight, still no leak.

I had to insist they take it off and treat it like a rim leak. No more
flat now.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's