Slow tire leak

[Smiling Jack]

I have one tire that has been losing about 5 psi per week over the last few months.

 

Local shop removed the wheel from the car and could not find a cause or location of the leak.  They took the tire off of the wheel and inspected it form the inside as well and still found nothing.

 

At that point, I hoped that it had a leak at the rim seal, and that removal and remounting would cure it.  No such luck!

 

Anyone have any thoughts ?

 

I am thinking of buying a new tire and wheel and keeping the wheel-mounted slow leaker as spare.

Edited October 4, 2014 by Smiling Jack

[DaveofDurham]

Did they change the valve stem when they took the tire off the rim?

[Smiling Jack]

Did they change the valve stem when they took the tire off the rim?

 

No.  They had soap-film tested at the valve beforehand and had decided that it was ok.

 

Do these valves with TPMS take the same stems as the ordinary valves?

 

Thanks for the thought, Dave.

 

Now I am thinking that wat I might do is swap valve stems with another one of my tires and see if the problem moves with the stem.

 

Any special precautions in replacing valve stems because of TPMS?

Edited October 4, 2014 by Smiling Jack

[obob]

Update: After re-reading your post I realize a screw would be unlikely, but I will just keep this post. Though I am very interested in the outcome.  I hope you find the cause and share it.

 

I had a slow leak on my C-Max that turned out to be a screw that went into the tire and the head of the screw wore off.  The first time I checked for leaks I did not notice it and it was not leaking fast enough for substantial bubble action from the soapy water.  Also my C-Max tires were filled with pebbles from a gravel parking lot I visit one a week.  I ended up picking out the pebbles with needle nose pliers.  That's when I encounter the "pebble" that didn't come out.  When I put the soapy water on it it did produce a small bubble very infrequently. 

 

It was slow enough that for quite a while I thought it was just bad seal at the bead, though it was frustrating, noticing when I checked my tires one tire down bit more than the rest.  But after a long trip the tire lost quite a bit of air, though not enough to have a low pressure warning.  So a tire in motion may leak more than one sitting still with soapy water on it.

 

Thought I would share that in case it could be useful.

Edited December 6, 2014 by obob

[plus 3 golfer]

See if the shop checked the alloy wheel for leaks.  I've heard of alloy wheels developing a crack where it's virtually impossible to detect visually and may not leak until under load while spinning.  I don't know what the best method is for finding and repairing such a crack. 

[Smiling Jack]

Obob:  Thanlks.  I suppose some leak in the tread could get worse and eventually show up.

 

Golfer:  That's one I did not think of.  I suppose one way to ferret that out would be to put a new tire on that wheel or put a new wheel on that tire.  I could do both in connection with my possible plan to get a new wheel and tire.

[Mark Snyder]

I've had my CMax for about four months, and have already had two flats.  The "Repair" kit is useless.  It's very dangerous traveling around without a spare.  I love the car, but the tire situation is horrid. You'd think they'd supply more durable tires.

[ScubaDadMiami]

I am with you on wishing for a spare. I drove 5,400+ miles to New England and back, and I lucked out, but worrying about getting a flat in a remote area was always on my mind.

[obob]

I am with you on wishing for a spare. I drove 5,400+ miles to New England and back, and I lucked out, but worrying about getting a flat in a remote area was always on my mind.

With this talk about a spare I posted this.

 

http://fordcmaxhybridforum.com/topic/4515-windstar-donut-spare/

 

 

ALSO Smiling Jack, I would be interested in how your tire problem concludes.

[stevedebi]

With this talk about a spare I posted this.

 

http://fordcmaxhybridforum.com/topic/4515-windstar-donut-spare/

 

 

ALSO Smiling Jack, I would be interested in how your tire problem concludes.

I would think it better to simply buy a spare rim from the dealer, then get a tire, if it is that important to you. Expensive, I know, but the best solution.

[wab]

See if the shop checked the alloy wheel for leaks.  I've heard of alloy wheels developing a crack where it's virtually impossible to detect visually and may not leak until under load while spinning.  I don't know what the best method is for finding and repairing such a crack. 

 

We thought we had one of those on our MKX, till the tire was dismounted.

1" very visible crack, couldn't believe it held air at all.

NTB has a contract with a local welder, no loss of air till we traded for the cmax.

 

At Discount Tire 2 weeks ago.

Discount Tire "Your TPMS is leaking"

BMW 6 (convertible): "So you're telling that the device that's supposed to tell me when I have a leak is leaking?"

Discount Tire: "uh Yea"

:drop:

 

 

[Smiling Jack]

With this talk about a spare I posted this.

 

http://fordcmaxhybridforum.com/topic/4515-windstar-donut-spare/

 

 

ALSO Smiling Jack, I would be interested in how your tire problem concludes.

 

Still losing about 5 psi per week on the average but some weeks less.  Have not been able to ID what makes a difference.

[ScubaDadMiami]

Have you checked to make sure that the valve has the Schrader valve screwed all the way in?

[Smiling Jack]

Have you checked to make sure that the valve has the Schrader valve screwed all the way in?

 

That was a good idea.

 

Update:  I still have a slow leak in that tire, but it has slowed to about 2 or 3 psi per week (from 5 psi per week in August and through September).

[Jus-A-CMax]

...did they do the wheel test in a water tank? that woud show bubbles...for some "well, you're Captain Obvious" - erh no, some tire places use the bottle spray method. They spray the tire and try and spot the bubbles. The tire place, Western Tires Burbank,  that my family use they use a water tank. The spray method is not that effective in difficult leaks - case in point, Maxine had a slow leak at Mammoth. 285 miles from home. Took it to a big tire dealer there, could not find it after 2 hrs. Left the car for 1 hr, no drop in psi. Drove it back to LA and it dropped some PSI midway home. Took it to Westen Tires in Burbank, they dropped it into the tank and -wallah- small leak was due to a shard of glass.

 

Jus my 2c.

Edited December 6, 2014 by Jus-A-CMax

[Adrian_L]

That's the first thing that popped into my head-----put the tire and wheel in a bathtub or equivalent.  But if it's only 2-5 psi per week, maybe no bubbles.

 

Probably worth a visit to a tire specialist for a second opinion.  A drag, to be sure.

[Jus-A-CMax]

I've had that sloooow leak as well - its off to Western Tires for me. They also do my Jags as well...great company, I have no quams shilling and shouting for this family owned biz...but yeah, I would be p*ssed as well. That incident with Mammoth really got me into thinking I am soooo screwed with no spare tire....we don't even have room for it since we pack Maxine to the hilt....poor girl.

[Adrian_L]

"Maxine"--I like that.  "Matilda" is my '85 Vandura camper van (10 mpg on LPG), but as yet our beloved 9-month old hybrid remains un-Christened.

[SPL Tech]

Take the wheel off, fill your bathtub with water and completely submerge the wheel. Come back in five minutes. That will identify the leak 1000 out of 1000 times.

Edited December 26, 2014 by SPL Tech

[Smiling Jack]

...did they do the wheel test in a water tank? that woud show bubbles...for some "well, you're Captain Obvious" - erh no, some tire places use the bottle spray method. They spray the tire and try and spot the bubbles. The tire place, Western Tires Burbank,  that my family use they use a water tank. The spray method is not that effective in difficult leaks - case in point, Maxine had a slow leak at Mammoth. 285 miles from home. Took it to a big tire dealer there, could not find it after 2 hrs. Left the car for 1 hr, no drop in psi. Drove it back to LA and it dropped some PSI midway home. Took it to Westen Tires in Burbank, they dropped it into the tank and -wallah- small leak was due to a shard of glass.

 

Jus my 2c.

 

Jus:  Thanks for that thought, and

Adrian:  thanks for seconding.

 

If the car had a proper jack, I would try that myself, but I'm so overloaded these days, I don't find the time to take the car anywhere.

 

And I was hoping that the leak would just keep slowing down.  SIlly me !

 

I got the low tire pressure warning the other day and was 20 psi down from the 45 I had filled on the 6th.  I'm starting to think that the leak is episodic rather than continuous.   That will make it really hard to find - even with a tank.

[drdiesel1]

Jus:  Thanks for that thought, and

Adrian:  thanks for seconding.

 

If the car had a proper jack, I would try that myself, but I'm so overloaded these days, I don't find the time to take the car anywhere.

 

And I was hoping that the leak would just keep slowing down.  SIlly me !

 

I got the low tire pressure warning the other day and was 20 psi down from the 45 I had filled on the 6th.  I'm starting to think that the leak is episodic rather than continuous.   That will make it really hard to find - even with a tank.

 

It sounds like a slow leak and when you park the car, it might cover the hole on rare occasions.

 

Here's my take on how to find this. I use a spray bottle (old windex) with soapy water. Spray around the valve

stem with the cap removed. Then move to the sidewall and rim lip area. You can do the tread on the car, but

if it's a rear tire it will make it harder to do. On the fronts you can just move the car with the wheel turned and

spot spray the tread. From what you're telling us, I would tend to think the TPMS seal could be a problem.

The TPMS has an o-ring/rubber grommet between the sensor stem and the wheel rim. If it's not properly installed

it very well could leak and change rates based on temperature changes.

Edited December 26, 2014 by drdiesel1

[homestead]

Take the wheel off, fill your bathtub with water and completely submerge the wheel. Come back in five minutes. That will identify the leak 1000 out of 1000 times.

You must be single. ;)

[mtb9153]

You must be single. ;)

works for me a nice DIY fix and I've been married for almost 29 years :wub2: to my beloved Denise

[Kelleytoons]

"Husband, darling, I'm going to go get cleaned up now and... OH MY GOD!!"

[SPL Tech]

You must be single. ;)

Tell her that either you put the tire in the tub, or she can go to Wal-Mart and buy you a plastic tub to put it in. Or just do it when she is away. Problem solved. What she doesent know cant hurt her. ;)