Ever have a slow leaking tire? Walk out of the house or office to find a flat or dangerously low tire that has leaked air out over a period of time. If you don't have access to an air compressor, or perhaps the spare is flat, don't drag out the jack just yet. Reach for the "Air Borrower" A coil of small diameter, easily storable air hose that will encircle the car at ground level and hook up to each valve stem. Equalizing the air in each tire. Say you have a fairly standard 35 lbs. in 3 of your tires, but the other one has slowly leaked down to 10 lbs. Hook up the air borrower and equalize them all to 28.75 lbs. unhook the apparatus and drive to a service station to get it fixed. Even if the tire was completely flat you would still be able to get 26.25 lbs. Of course this wouldnt work on a tire with a gigantic hole in it, or one you had driven on a flat and broken off the rim. But for the slow leaker It seems this might be an easier fix when no compressed air is available.-- hard-scrabble, Mar 28 2003 Emergency Tire Inflator http://www.cornerha..._Tire_Inflator.html [DrCurry, Oct 17 2004, last modified Oct 21 2004] Small, Inexpensive Tire Inflator http://doitbest.com...6&sku=572810&SAFE=1Here is the one I have; I got it from Wal-Borg [Knife Knut, Jan 24 2005] Just get down on your knees and blow *really hard*.
If you have space in your trunk for one of these, you have space for one of those little compressed air emergency tire inflators.-- DrCurry, Mar 28 2003 Make sure you look for a puncture first, or all your tires will be at 10psi.-- phoenix, Mar 28 2003 Why even have inflatable tires? Just have solid rubber tires like on a tricycle.-- mrthingy, Mar 28 2003 too heavy and expensive.. but if the treads wear out just have them recut to a slightly smaller diameter-- tazmase2, Jul 27 2003 Fishbone. A small automotive tire compressor which plugs into the cig lighter can be had for under $15. With use, It will pay for itself by reducing tire wear.-- Knife Knut, Jan 24 2005 Because air does not compress significantly at automotive tire pressures, the idea of a tire is fundamentally to hold a certain volume of pressurized air. Pumping up a completely flat tire requires pressurizing a volume of air equal to the difference between the tire's "flat" volume and its "properly-inflated" volume. When a tire goes flat, the problem isn't that it's lost pressure, but rather that it's lost volume.
Connecting a tire that's at 35psi to one that's at 25psi won't result in both tires being at 30psi. More likely you'd end up with both tires at about 27psi (since a tire loses a lot more volume going from 26psi to 25psi than from 35psi to 34psi).-- supercat, Jan 25 2005 Croissant. Perfectly sound half baked idea. In fact, I'm tempted to get me a length of hose and use this idea. Might start overpumping all my tyres so I have spare air... (JOKE, don't try this at home).
I think a 35psi and 25psi tyre should even out at greater than 30psi. It would average to 30 if you were measuring non-expanding containers. But because tyres expand when filled, the 35psi tyre has more air at 35psi than the less filled tyre has at 25psi.-- Mat-C, Jun 28 2005 I've seen this baked--before this idea was posted--thought it was silly then.-- baconbrain, Jun 28 2005 The pressures in the tyres would equalise. but if the load in the vehicle was uneven, then the tyres on the loaded axel would contain less volume of air. Ideally you would need to completely unload the vehicle. This is true of normal tyre pressures also, I suppose.....-- Minimal, Jun 28 2005 Fully baked.
I've seen this exact idea in use in off-road applications, by people who had enormous tires, plus a couple of enormous spares they'd rather not wrestle into service, and also a contraption called a "chuffer," which screwed into a sparkplug hole and filled a tire that way.
You think Fix-a-Flat is flammable!-- elhigh, Jun 28 2005 i was about to post this. Good idea, i need one ( i have a slow leak on my el camino) [+] people say its baked, can you provide a link?-- bleh, Jan 12 2007 I would make a suggestion similar to the one that Dr. Curry made- Having something like that in your trunk would also permit you to have a $2 bicycle hand pump in your trunk. It may take a little while to pump up the tire but it really works. I carry around one so that if I do get a flat, I can make it to the next gas station.-- Jscotty, Jan 12 2007 Why on earth would you take air from your own tires? Aren't there other cars in that parking lot? A whole parking lot full of compressed air? You have a hose, boy, you help yourself.-- ldischler, Jan 12 2007 random, halfbakery