Replacing innertubes without replacing tires?

[Ben Jackson]

I picked up a set of airstop-style tubes in my last AC Spruce order. I
was reviewing tire maintenance procedures and saw a recommendation that
you not re-use innertubes because they set slightly stretched and there's
a risk of pinching or folding them when they are reinstalled.

So, considering these tubes are new and my tires are decidedly NOT, would
I be "wasting" the new tubes on the old tires, or would it be okay to
reuse them on a future new tire?

--
Ben Jackson AD7GD
>
http://www.ben.com/

[Gene Seibel]

I have reused tubes a number of times, usually successfully. When I
took them out after the second use, there was evidence that some folds
had developed. Once out of perhaps a dozen times did one develop a
small leak at the end of a fold.
--
Gene Seibel
Gene & Sue's Aeroplanes - http://pad39a.com/gene/planes.html
Because we fly, we envy no one.



Ben Jackson wrote:
> I picked up a set of airstop-style tubes in my last AC Spruce order. I
> was reviewing tire maintenance procedures and saw a recommendation that
> you not re-use innertubes because they set slightly stretched and there's
> a risk of pinching or folding them when they are reinstalled.
>
> So, considering these tubes are new and my tires are decidedly NOT, would
> I be "wasting" the new tubes on the old tires, or would it be okay to
> reuse them on a future new tire?
>
> --
> Ben Jackson AD7GD
> >
> http://www.ben.com/

[RK Henry]

On Thu, 26 Oct 2006 14:30:56 -0500, Ben Jackson > wrote:

>I picked up a set of airstop-style tubes in my last AC Spruce order. I
>was reviewing tire maintenance procedures and saw a recommendation that
>you not re-use innertubes because they set slightly stretched and there's
>a risk of pinching or folding them when they are reinstalled.
>
>So, considering these tubes are new and my tires are decidedly NOT, would
>I be "wasting" the new tubes on the old tires, or would it be okay to
>reuse them on a future new tire?

How "decidedly not" new are the existing tires? If they're going to be
replaced soon, you could store the tubes until you need them. Of
course you run the risk that you might sell the airplane before that.

A&Ps have replaced several tires on my Warrior without replacing the
tubes. They always told me that they don't replace tubes as long as
there's nothing wrong with them. One time I finally had them put new
tubes in my old tires. For all I could tell, those tubes may have been
on the airplane since it was new. The new tubes really cut down on air
loss from the tires.

RK Henry

[Terry]

I've done it. No problem, my advice is to use talc powder inside the
tire. Use
plenty and the "new" tube will slip in the old tire with no hang-ups.

You can do it!

Terry
N6401F

"Ben Jackson" > wrote in message
...
>I picked up a set of airstop-style tubes in my last AC Spruce order.
>I
> was reviewing tire maintenance procedures and saw a recommendation
> that
> you not re-use innertubes because they set slightly stretched and
> there's
> a risk of pinching or folding them when they are reinstalled.
>
> So, considering these tubes are new and my tires are decidedly NOT,
> would
> I be "wasting" the new tubes on the old tires, or would it be okay
> to
> reuse them on a future new tire?
>
> --
> Ben Jackson AD7GD
> >
> http://www.ben.com/

[Gig 601XL Builder]

"Terry" > wrote in message
. net...
> I've done it. No problem, my advice is to use talc powder inside the tire.
> Use
> plenty and the "new" tube will slip in the old tire with no hang-ups.
>
> You can do it!
>
> Terry
> N6401F

I put my tubes and tires on my plane recently and since my wife was heading
to the store I asked her to pick me up some talc. She brings in what she
said was the only powder she could find with talc instead of corn starch. I
have the prettiest smelling tires at the airport.

[Fly]

Talc powder helps alot. I always inflate then let the air completely out
again which should allow any folds or such to relax.

Some tubes have molding lines which can signal how much the tube has fretted
inside the tire. If a close inspection doesn't reveal much wear or
abrasion, I'll reuse them.

Kent Felkins

[Ben Jackson]

On 2006-10-26, RK Henry > wrote:
> On Thu, 26 Oct 2006 14:30:56 -0500, Ben Jackson > wrote:
>
> How "decidedly not" new are the existing tires? If they're going to be
> replaced soon, you could store the tubes until you need them. Of
> course you run the risk that you might sell the airplane before that.

They're not new but they don't seem to be wearing out. So as you say,
they might have a long, happy life ahead of them, in which case I'd
like to get the new tubes in and quit inflating them all the time!

> A&Ps have replaced several tires on my Warrior without replacing the
> tubes. They always told me that they don't replace tubes as long as
> there's nothing wrong with them.

Thanks to everyone for the responses.

--
Ben Jackson AD7GD
>
http://www.ben.com/

[[email protected]]

I never knew you were supposed to replace tubes. I went > 30 years
on a set in my Bonanza.

Now that they are replaced, I can say the new ones leak about
as much as the 30 year old ones.

Bill Hale

Ben Jackson wrote:
> On 2006-10-26, RK Henry > wrote:
> > On Thu, 26 Oct 2006 14:30:56 -0500, Ben Jackson > wrote:
> >
> > How "decidedly not" new are the existing tires? If they're going to be
> > replaced soon, you could store the tubes until you need them. Of
> > course you run the risk that you might sell the airplane before that.

> Ben Jackson AD7GD
> >
> http://www.ben.com/

[Ben Jackson]

On 2006-11-01, > wrote:
>
> Now that they are replaced, I can say the new ones leak about
> as much as the 30 year old ones.

My new ones are butyl based (not "airstop", but another brand). They
should hold their air much longer.

--
Ben Jackson AD7GD
>
http://www.ben.com/

[Gig 601XL Builder]

"Ben Jackson" > wrote in message
...
> On 2006-11-01, > wrote:
>>
>> Now that they are replaced, I can say the new ones leak about
>> as much as the 30 year old ones.
>
> My new ones are butyl based (not "airstop", but another brand). They
> should hold their air much longer.
>
> --
> Ben Jackson AD7GD
> >
> http://www.ben.com/

Fill them with Nitrogen they won't leak as much. Not that I've tried it.

[Ben Jackson]

On 2006-11-01, Gig 601XL Builder <> wrote:
>
> Fill them with Nitrogen they won't leak as much. Not that I've tried it.

The way my A&P drives a nitrogen cylinder they wouldn't leak because
the wheel halves would be in different counties...

--
Ben Jackson AD7GD
>
http://www.ben.com/

[Ray Andraka]

Gig 601XL Builder wrote:

>
>
> Fill them with Nitrogen they won't leak as much. Not that I've tried it.
>
>
How do you figure that? Air is already mostly nitrogen. Why would a
higher concentration of nitrogen leak any less than plain old air? The
difference in atom sizes between nitrogen and the other major
constituents of air is on the order of a few percent, so even the other
constituents aren't going to leak out leaving just nitrogen.

[Capt. Geoffrey Thorpe]

"Ray Andraka" > wrote in message
...
> Gig 601XL Builder wrote:
>
>>
>>
>> Fill them with Nitrogen they won't leak as much. Not that I've tried it.
> How do you figure that? Air is already mostly nitrogen. Why would a
> higher concentration of nitrogen leak any less than plain old air? The
> difference in atom sizes between nitrogen and the other major constituents
> of air is on the order of a few percent, so even the other constituents
> aren't going to leak out leaving just nitrogen.

And, that few percent difference makes a small fraction of a percent
difference in how fast they leak. Not enough to notice, but enough that tire
stores around here (Detroit) make all kinds of wild claims about the
advantages of buying tires from them and having them filled with N2...

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

[RST Engineering]

Because back in the good old daze when inner tubes weren't quite as well
done from a chemistry point of view the oxygen in the air WOULD attack the
rubber and cause it to deteriorate quicker than with pure nitrogen. Back
when I wuz wit da airlines, we used nitrogen exclusively to fill tires on
the torches.

Jim



"Capt. Geoffrey Thorpe" <The Sea Hawk at wow way d0t com> wrote in message
news:hdSdnbmXe9pLpNTYnZ2dnUVZ_sidnZ2d@wideopenwest .com...
> "Ray Andraka" > wrote in message
> ...
>> Gig 601XL Builder wrote:
>>
>>>
>>>
>>> Fill them with Nitrogen they won't leak as much. Not that I've tried it.
>> How do you figure that? Air is already mostly nitrogen. Why would a
>> higher concentration of nitrogen leak any less than plain old air? The
>> difference in atom sizes between nitrogen and the other major
>> constituents of air is on the order of a few percent, so even the other
>> constituents aren't going to leak out leaving just nitrogen.
>
> And, that few percent difference makes a small fraction of a percent
> difference in how fast they leak. Not enough to notice, but enough that
> tire stores around here (Detroit) make all kinds of wild claims about the
> advantages of buying tires from them and having them filled with N2...
>
> --
> Geoff
> The Sea Hawk at Wow Way d0t Com
> remove spaces and make the obvious substitutions to reply by mail
> When immigration is outlawed, only outlaws will immigrate.
>

[Gig 601XL Builder]

"Ray Andraka" > wrote in message
...
> Gig 601XL Builder wrote:
>
>>
>>
>> Fill them with Nitrogen they won't leak as much. Not that I've tried it.
> How do you figure that? Air is already mostly nitrogen. Why would a
> higher concentration of nitrogen leak any less than plain old air? The
> difference in atom sizes between nitrogen and the other major constituents
> of air is on the order of a few percent, so even the other constituents
> aren't going to leak out leaving just nitrogen.

As I said I haven't tried it but there are 398,000 hits when you Google
Nitrogen filled tires. I saw and ad for it in one of the aircraft mags the
other day and hadn't really looked into it that much. But glancing at the
Google results the opinions are mixed between works well and snake oil.

[Ray Andraka]

Gig 601XL Builder wrote:
> "Ray Andraka" > wrote in message
> ...
>
>>Gig 601XL Builder wrote:
>>
>>
>>>
>>>Fill them with Nitrogen they won't leak as much. Not that I've tried it.
>>
>>How do you figure that? Air is already mostly nitrogen. Why would a
>>higher concentration of nitrogen leak any less than plain old air? The
>>difference in atom sizes between nitrogen and the other major constituents
>>of air is on the order of a few percent, so even the other constituents
>>aren't going to leak out leaving just nitrogen.
>
>
> As I said I haven't tried it but there are 398,000 hits when you Google
> Nitrogen filled tires. I saw and ad for it in one of the aircraft mags the
> other day and hadn't really looked into it that much. But glancing at the
> Google results the opinions are mixed between works well and snake oil.
>
>

There are reasons for using nitrogen in tires, but leakage isn't one of
them. From what I understand, high pressure tires often need nitrogen
because if regular air was used the high pressure of the oxygen mix
becomes combustible and can lead to tire fires. In our spam cans
though, the pressures aren't high enough to cause problems. There's
also the convenience thing if you happen to have bottled nitrogen in the
hangar, and finally some have said that it keeps the rubber from
oxidizing, but I doubt that is a real issue since the outsides will
deteriorate long before the inside oxidizes enough to be a problem.

[Mike Noel]

I don't know the practical aspects of N2 v O2 in modern tubes, but the
partial pressure of O2 in a tire inflated to 30 psi is 3x that on the
outside of the tube. If anything in the rubber tended to oxidize, it would
oxidize significantly faster at the higher O2 partial pressure.
It may not be a practical problem in tubes, but I'll bet it makes a
difference in a strut (1000 psi?)

--
Best Regards,
Mike

http://photoshow.comcast.net/mikenoel

"Ray Andraka" > wrote in message
...
> Gig 601XL Builder wrote:
>> "Ray Andraka" > wrote in message
>> ...
>>
>>>Gig 601XL Builder wrote:
>>>
>>>
>>>>
>>>>Fill them with Nitrogen they won't leak as much. Not that I've tried it.
>>>
>>>How do you figure that? Air is already mostly nitrogen. Why would a
>>>higher concentration of nitrogen leak any less than plain old air? The
>>>difference in atom sizes between nitrogen and the other major
>>>constituents of air is on the order of a few percent, so even the other
>>>constituents aren't going to leak out leaving just nitrogen.
>>
>>
>> As I said I haven't tried it but there are 398,000 hits when you Google
>> Nitrogen filled tires. I saw and ad for it in one of the aircraft mags
>> the other day and hadn't really looked into it that much. But glancing at
>> the Google results the opinions are mixed between works well and snake
>> oil.
>
> There are reasons for using nitrogen in tires, but leakage isn't one of
> them. From what I understand, high pressure tires often need nitrogen
> because if regular air was used the high pressure of the oxygen mix
> becomes combustible and can lead to tire fires. In our spam cans though,
> the pressures aren't high enough to cause problems. There's also the
> convenience thing if you happen to have bottled nitrogen in the hangar,
> and finally some have said that it keeps the rubber from oxidizing, but I
> doubt that is a real issue since the outsides will deteriorate long before
> the inside oxidizes enough to be a problem.

[Gig 601XL Builder]

"Mike Noel" > wrote in message
. ..
>I don't know the practical aspects of N2 v O2 in modern tubes, but the
>partial pressure of O2 in a tire inflated to 30 psi is 3x that on the
>outside of the tube. If anything in the rubber tended to oxidize, it would
>oxidize significantly faster at the higher O2 partial pressure.
> It may not be a practical problem in tubes, but I'll bet it makes a
> difference in a strut (1000 psi?)

Is anybody suggesting the use of O2?

[[email protected]]

Gig 601XL Builder <wrDOTgiaconaATcox.net> wrote:

> "Mike Noel" > wrote in message
> . ..
> >I don't know the practical aspects of N2 v O2 in modern tubes, but the
> >partial pressure of O2 in a tire inflated to 30 psi is 3x that on the
> >outside of the tube. If anything in the rubber tended to oxidize, it would
> >oxidize significantly faster at the higher O2 partial pressure.
> > It may not be a practical problem in tubes, but I'll bet it makes a
> > difference in a strut (1000 psi?)

> Is anybody suggesting the use of O2?

How do you not use O2 if you use air?

--
Jim Pennino

Remove .spam.sux to reply.

[Gig 601XL Builder]

> wrote in message
...
> Gig 601XL Builder <wrDOTgiaconaATcox.net> wrote:
>
>> "Mike Noel" > wrote in message
>> . ..
>> >I don't know the practical aspects of N2 v O2 in modern tubes, but the
>> >partial pressure of O2 in a tire inflated to 30 psi is 3x that on the
>> >outside of the tube. If anything in the rubber tended to oxidize, it
>> >would
>> >oxidize significantly faster at the higher O2 partial pressure.
>> > It may not be a practical problem in tubes, but I'll bet it makes a
>> > difference in a strut (1000 psi?)
>
>> Is anybody suggesting the use of O2?
>
> How do you not use O2 if you use air?
>

Well if we are going to call using "air" using O2 we might as well call it
using N2. There is a lot more N than O.

[[email protected]]

Gig 601XL Builder <wrDOTgiaconaATcox.net> wrote:

> > wrote in message
> ...
> > Gig 601XL Builder <wrDOTgiaconaATcox.net> wrote:
> >
> >> "Mike Noel" > wrote in message
> >> . ..
> >> >I don't know the practical aspects of N2 v O2 in modern tubes, but the
> >> >partial pressure of O2 in a tire inflated to 30 psi is 3x that on the
> >> >outside of the tube. If anything in the rubber tended to oxidize, it
> >> >would
> >> >oxidize significantly faster at the higher O2 partial pressure.
> >> > It may not be a practical problem in tubes, but I'll bet it makes a
> >> > difference in a strut (1000 psi?)
> >
> >> Is anybody suggesting the use of O2?
> >
> > How do you not use O2 if you use air?
> >

> Well if we are going to call using "air" using O2 we might as well call it
> using N2. There is a lot more N than O.

Nobody but you used the phrase "use O2", notice the phrase "partial pressure"
in the original post.

--
Jim Pennino

Remove .spam.sux to reply.

[Gig 601XL Builder]

> wrote in message
...
> Gig 601XL Builder <wrDOTgiaconaATcox.net> wrote:
>
>> > wrote in message
>> ...
>> > Gig 601XL Builder <wrDOTgiaconaATcox.net> wrote:
>> >
>> >> "Mike Noel" > wrote in message
>> >> . ..
>> >> >I don't know the practical aspects of N2 v O2 in modern tubes, but
>> >> >the
>> >> >partial pressure of O2 in a tire inflated to 30 psi is 3x that on the
>> >> >outside of the tube. If anything in the rubber tended to oxidize, it
>> >> >would
>> >> >oxidize significantly faster at the higher O2 partial pressure.
>> >> > It may not be a practical problem in tubes, but I'll bet it makes a
>> >> > difference in a strut (1000 psi?)
>> >
>> >> Is anybody suggesting the use of O2?
>> >
>> > How do you not use O2 if you use air?
>> >
>
>> Well if we are going to call using "air" using O2 we might as well call
>> it
>> using N2. There is a lot more N than O.
>
> Nobody but you used the phrase "use O2", notice the phrase "partial
> pressure"
> in the original post.

Read the first sentence in Mikes post and notice the phrase "I don't know
the practical aspects of N2 v O2 in modern tubes,..."

[[email protected]]

Gig 601XL Builder <wrDOTgiaconaATcox.net> wrote:

> > wrote in message
> ...
> > Gig 601XL Builder <wrDOTgiaconaATcox.net> wrote:
> >
> >> > wrote in message
> >> ...
> >> > Gig 601XL Builder <wrDOTgiaconaATcox.net> wrote:
> >> >
> >> >> "Mike Noel" > wrote in message
> >> >> . ..
> >> >> >I don't know the practical aspects of N2 v O2 in modern tubes, but
> >> >> >the
> >> >> >partial pressure of O2 in a tire inflated to 30 psi is 3x that on the
> >> >> >outside of the tube. If anything in the rubber tended to oxidize, it
> >> >> >would
> >> >> >oxidize significantly faster at the higher O2 partial pressure.
> >> >> > It may not be a practical problem in tubes, but I'll bet it makes a
> >> >> > difference in a strut (1000 psi?)
> >> >
> >> >> Is anybody suggesting the use of O2?
> >> >
> >> > How do you not use O2 if you use air?
> >> >
> >
> >> Well if we are going to call using "air" using O2 we might as well call
> >> it
> >> using N2. There is a lot more N than O.
> >
> > Nobody but you used the phrase "use O2", notice the phrase "partial
> > pressure"
> > in the original post.

> Read the first sentence in Mikes post and notice the phrase "I don't know
> the practical aspects of N2 v O2 in modern tubes,..."

Keep reading; this is followed by "...but the partial pressure of O2 in
a tire...".

From http://en.wikipedia.org/wiki/Partial_pressure

"In a mixture of ideal gases, each gas has a partial pressure which is
the pressure which the gas would have if it alone occupied the volume."

Clearly, the original poster was referring to a mixture of gases that
contains O2, i.e. air.

--
Jim Pennino

Remove .spam.sux to reply.

[Mike Spera]

I always replaced tires and tubes together. For the additional $30 for a
new tube, I always thought it was false economy to reuse them. As some
have acknowledged, the tubes stretch and may fold upon reuse. I usually
see cracking around the valve stem on a used tube. Perhaps reuse would
be an option if we flew 250 hours a year and wore out tires sooner. But
we usually have tires for 4 years or so. By then, I usually see the
valve stem starting to crack and the sidewalls cracking on the tires.

It seems like cheap insurance. But, others swear by reusing tubes. This
is a pretty good case of how different people will accept differing
degrees of maintenance. Absent any Advisory Circular or maintenance
manual prohibition against reusing tubes, it is "legal" to do so.

Nitrogen in the tires? I don't even use nitrogen in the struts.

Good Luck,
Mike

[Stealth Pilot]

On Thu, 26 Oct 2006 14:30:56 -0500, Ben Jackson > wrote:

>I picked up a set of airstop-style tubes in my last AC Spruce order. I
>was reviewing tire maintenance procedures and saw a recommendation that
>you not re-use innertubes because they set slightly stretched and there's
>a risk of pinching or folding them when they are reinstalled.
>
>So, considering these tubes are new and my tires are decidedly NOT, would
>I be "wasting" the new tubes on the old tires, or would it be okay to
>reuse them on a future new tire?

ben reusing the tubes is not a froblem if they are in good condition
and not perished.

you can save yourself a lot of grief in the long run if you replace
the schrader valves with each new tyre. use aviation high pressure
shraders and you should have no problems at all.
the valves do wear out and if the tyre goes flat everytime the valve
is at the bottom of the hub you have a worn out schrader core.

Stealth Pilot

[Fly]

I wish I could be like you guys and be able to say I never had a flat due to
a worn tube.
Unfortunately, I discovered how difficult it is to taxi with a flat. Dang
those flight school planes.

Kent Felkins

[Ben Jackson]

On 2006-11-05, Fly <> wrote:
> Unfortunately, I discovered how difficult it is to taxi with a flat. Dang
> those flight school planes.

On a slightly related note, I always saw flat spots on the tires of
rental airplanes and I wondered if I'd been responsible for any of them.
Now that I've had the same set of tires for hundreds of landings I know
it must be harder than I thought to flat-spot a tire.

--
Ben Jackson AD7GD
>
http://www.ben.com/

[Stealth Pilot]

On Sun, 05 Nov 2006 14:35:48 -0600, Ben Jackson > wrote:

>On 2006-11-05, Fly <> wrote:
>> Unfortunately, I discovered how difficult it is to taxi with a flat. Dang
>> those flight school planes.
>
>On a slightly related note, I always saw flat spots on the tires of
>rental airplanes and I wondered if I'd been responsible for any of them.
>Now that I've had the same set of tires for hundreds of landings I know
>it must be harder than I thought to flat-spot a tire.

no....
the tyres are out of balance.
after takeoff when the wheel finally spins to a stop the heavy part of
the wheel naturally points down. this means that the same part of the
tyre actually bears the wear of touchdown as the tyre is spun up to
landing speed.
thats why there are flat spots.

Stealth Pilot

[Dave Butler[_1_]]

Ben Jackson wrote:

> On a slightly related note, I always saw flat spots on the tires of
> rental airplanes and I wondered if I'd been responsible for any of them.
> Now that I've had the same set of tires for hundreds of landings I know
> it must be harder than I thought to flat-spot a tire.

It must be easy to do in a Mooney. A club I belonged to for a while was
constantly having flat-spotted mains on their Mooneys, and I've also
seen it on the Mooney I own with partners. I may have been responsible
for some of that when I first joined the partnership. I started being
more careful about braking and the flat-spots haven't come back. I get
smoother landings if I don't land in a full stall, and all the weight
doesn't come on the wheels 'til you've slowed down a bit. If you start
braking too early it's easy to lock up the mains and not feel it.