The future of automotive jacks?

[EM1FTW]

Has anyone seen this before?
it looks like a pretty cool idea, as long as it works as advertised.


Lift your vehicle in 30 seconds without straining with an awkward, unstable jack. Simply fit the Air Jack's hose over your exhaust, position the airbag under the vehicle, and turn on your engine. The exhaust inflates the bag, lifting the vehicle to 17". A one-way valve keeps the bag inflated after the engine has been turned off. The durable Air Jack was originally designed for rugged off-road use and works in mud, snow, and uneven ground where a regular jack cannot. Has no negative effects on the engine. Comes in a handy carry case to fit easily in your trunk.


Product Site (http://ajprindle.com/products/sku-14117.html)


Video Here! (http://www.youtube.com/watch?v=lOmAe-WKQmo)

[Cooked Rice]

Anyone else seeing this as a death trap?

[sjaswal]

the compressed air(bag) jacks on costco.com (u.s. site) would be nice
http://www.costco.com/Browse/Productgroup.aspx?Prodid=11071422&whse=BC&Ne=4000000&eCat=BC|3960|21277|61837&N=4018446&Mo=7&pos=4&No=7&Nr=P_CatalogName:BC&cat=61837&Ns=P_Price|1||P_SignDesc1&lang=en-US&Sp=C&ec=BC-EC22577-Cat21277&topnav=

if the link works

[vengie]

id be very skeptical climbing under my car with nothing but an airbag holding it up... as cool of an idea as it is i'll stick with my conventional way of jacking the car up

[EM1FTW]

here is another link to the product
http://www.airjackusa.com/index.htm

[Kloubek]

Can't be any worse than my Audi jack which snapped in half on me.....

[extm88]

maybe handy to jack up and then put stand underneath.
hell i sometimes dont feel safe underneath with jackstands.

[Mibz]

Has no negative effects on the engine.Yeah I can't really see this being true. It runs a check valve to prevent it deflating which means there's going to be x amount of pressure in the airbag trying to push the valve closed and the engine needs to put out x + 1 pressure in order to inflate it. The amount of pressure required to lift a car has -got- to be enough that you're putting your engine under insane stress trying to push those gases out.

I could be wrong, but it doesn't make sense (in my head) that this is harmless.

[extm88]

Originally posted by Kloubek
Can't be any worse than my Audi jack which snapped in half on me.....

haha i dont know if its the same as the vw ones but i have heard that the vw and e36 bmws jacks are reffered to as widow makers!
So your story doesnt surprise me lol.

[Supa Dexta]

Had a nissan one collapse on me.. well beside me.. before.

[PremiumRSX]

haha this is kinda cool. I wouldn't work underneath it, but hey if its just changing a wheel.. why not.

[EM1FTW]

Originally posted by PremiumRSX
haha this is kinda cool. I wouldn't work underneath it, but hey if its just changing a wheel.. why not.
kind of what I was thinking!

I would imagine this air jack would work alot better for the 4x4 guys out on trails

[Supa Dexta]

I'm curious as to how this works.. It mentions a 1 way valve.. But even so, whats the PSI within the bag.. I would think the leaks in your exhaust system would be a quick escape before it would want to inflate too much.. :dunno: And how does it fasten to the tail pipe, it just looks like a plastic trumpet end.

[extm88]

Originally posted by PremiumRSX
haha this is kinda cool. I wouldn't work underneath it, but hey if its just changing a wheel.. why not.

I wouldnt,
ide rather be a female and call ama than risk my car coming down on the braking system.
imagine what was just a flat tire is now a busted rotor as well.

[Supa Dexta]

Yeah screw this.. It can't work... I also notice the hose is never fully in the picture.

[SCHIDER23]

WOW that is the most moronic thing ever created, I can't believe people even consider using this, I know firefighters and tow truck drivers use heavy duty air bags, but they are reinforced and use an actual compressor to fill them up. I just don't see this been that efficient wow.:banghead:

[digi355]

Originally posted by Mibz
Yeah I can't really see this being true. It runs a check valve to prevent it deflating which means there's going to be x amount of pressure in the airbag trying to push the valve closed and the engine needs to put out x + 1 pressure in order to inflate it. The amount of pressure required to lift a car has -got- to be enough that you're putting your engine under insane stress trying to push those gases out.

I could be wrong, but it doesn't make sense (in my head) that this is harmless.

The compression ratio of your engine is say 10:1, the environment is at 1. The ball inflates to a pressure that is greater than that of environment say 3, but it does not exceed that of the engine. The engine shouldn’t know the difference; the “air” takes the path of least resistance.

[Supa Dexta]

The exhaust system is far from sealed, and kills people when snow backs up the flow of exhaust. This has to be bogus.

[95teetee]

"Lift your vehicle in 30 seconds without straining with an awkward, unstable jack"


I'll stick with lifting my (heavy-ass) car in 15 seconds with an awkward, unstable floor jack , thanks:D

[scat19]

Yeah I like my mechanical jack, thanks.

I wouldn't use it. I bet chicks would buy this, and their bf/husband would be like WTF were you thinking?

[EM1FTW]

Originally posted by scat19
Yeah I like my mechanical jack, thanks.

I wouldn't use it. I bet chicks would buy this, and their bf/husband would be like WTF were you thinking?

yes exactly!

[phrozen]

Actually these are pretty effective, and AMA uses these sometimes, I know if it is powered by exhaust, but it sure works, a friend of mine called AMA cause he had a flat and it jacked up his SUV like nothing.

[Zero102]

Some of you guys are looking at this wrong. The compression ratio of your engine has nothing at all to do with it, as the air leaving the cylinders has expanded several times over due to the temperature difference.

For the guy arguing about the "insane stress" your engine would be under, it all depends on the surface area of the bag. The link doesn't work for me and I am too lazy to google it right now, but look at it this way.
You need to lift 1/2 of the car's weight, let's say 2000lbs. You are lifting it with an airbag, so you need to consider the surface area of the bag contacting the car to find the required pressure to make the lift. Let's say the bag is 12"x24", that gives it a surface area of 288 square inches. 2000lbs/288 square inches = 6.944psi. Now if your exhaust system doesn't leak anywhere (and I mean massive leaks), it should have no problem at all generating this kind of pressure. Heck, 30-40psi from your exhaust should be obtainable before you see any side effects. I mean, consider the pressure ratios of exhaust to intake pressures on turbocharged engines. If 7PSI would blow up your engine how do many turbocharged cars run 30-40psi in the exhaust?
Of course, those pressures are pre-turbo, and there are a number of other things that could get damaged, but seriously, at 7psi I don't think you have much to worry about. I can't imagine all your exhaust gaskets blowing out or any other catastrophic failures at such low pressures, and that definitely wouldn't have any impact on your engine.

[alloroc]

It could work just fine.

Woudn't want to store in either of my hatchbacks/wagons after using it thought. The missus wouldn't be too pleased with the smell eminating from the back of the hatch.

[HHURICANE1]

We have an air hose at home for pumping up tires that you remove a spark plug and thread into the hole, fire up the engine and the engine acts as the air compressor. When you think about it all that an engine really is a big air compressor. Works like a darn.

[Mibz]

Originally posted by Zero102
Some of you guys are looking at this wrong. The compression ratio of your engine has nothing at all to do with it, as the air leaving the cylinders has expanded several times over due to the temperature difference.

For the guy arguing about the "insane stress" your engine would be under, it all depends on the surface area of the bag. The link doesn't work for me and I am too lazy to google it right now, but look at it this way.
You need to lift 1/2 of the car's weight, let's say 2000lbs. You are lifting it with an airbag, so you need to consider the surface area of the bag contacting the car to find the required pressure to make the lift. Let's say the bag is 12"x24", that gives it a surface area of 288 square inches. 2000lbs/288 square inches = 6.944psi. Now if your exhaust system doesn't leak anywhere (and I mean massive leaks), it should have no problem at all generating this kind of pressure. Heck, 30-40psi from your exhaust should be obtainable before you see any side effects. I mean, consider the pressure ratios of exhaust to intake pressures on turbocharged engines. If 7PSI would blow up your engine how do many turbocharged cars run 30-40psi in the exhaust?
Of course, those pressures are pre-turbo, and there are a number of other things that could get damaged, but seriously, at 7psi I don't think you have much to worry about. I can't imagine all your exhaust gaskets blowing out or any other catastrophic failures at such low pressures, and that definitely wouldn't have any impact on your engine. Thanks, that makes sense.

[VW337]

How about when the air in the bag cools down? Wouldn't the pressure inside the bag decrease as the temp of the air in the bag decreased??

[Cooked Rice]

What if you have a leaky ass exhaust? haha.

[Zero102]

Originally posted by VW337
How about when the air in the bag cools down? Wouldn't the pressure inside the bag decrease as the temp of the air in the bag decreased??

Point taken, that is correct, the pressure in the bag is directly proportional to the absolute temperature. The air leaving your exhaust (if your cat is working properly) will be ~50-70*C, (~320-340*K), once cooled to ambient it has dropped to 10-30*C (~280-300*K). This gives a percentage change of roughly 10-15%, so the pressure in the bag would decrease by 10-15%. You should be more worried about the water vapor condensing out and the volume change that would make in these cases.

My math and explanations here are crude I know, but really you would see probably a 10-30% decrease in bag pressure as the air inside cools down, but likely you would significantly over-inflate the bag when lifting the car so I doubt you would see the car come down at all (likely pressures in the bag would be 15-20psi, so a 30% decrease means it is still fine).

Above I mentioned that the compression ratio of the car has nothing to do with it due to the air heating, but really I made 2 explanations into 1. The compression ratio is irrelevant, but the relevant quantity is engine displacement, throttle position and engine speed, or the quantity of air moving through the intake, the other relevant factor is the heating of the air during combustion (although this is later negated). Unfortunately the heating will be canceled once the air in the bag has cooled.

I have done too much astrophysics today to rationalize this one out... now, if the bag were a polytrope and we were solving the density of the material relative to its center, then I could offer some more accurate suggestions... Kind of like the old physicists joke.. something about reducing cows to point masses,.

[texasnick]

They do this exact thing in Australia to get trucks unstuck when you don't have a jack. There's a show called "Bush Mechanics" I think that shows how it works. Pretty cool if you ask me. Not sure I would use this method to work underneath a car, but certainly as a way to "unstick" the car if a jack is unavailable.

But then you get into the question of "If you don't even have a jack, why would you have a giant inflatable bag?"

[Antonito]

Originally posted by texasnick


But then you get into the question of "If you don't even have a jack, why would you have a giant inflatable bag?"

Bingo.

[barmanjay]

I would use one,.. but have jack stands ready,.. by no means would I crawl under with that bag inflated.

I think this would be a great tool for offroad, in the event of getting unstuck.

[rumeo]

If youre emo enough, this would be great for suicide as well lol
fill the bag and inhale

[D911]

that bag seemed to lift that corrolla pretty high up..
I would imagine something with a higher center of gravity...like a work van might just tip over if it was fully inflated.

That'd be an interesting law suit.

[Moe Man]

i dont believe it is marketed towards doing oil changes or tranny swaps, it is just ment to be used it uneven surfaces mainly.

i wonder if there is an odour from the bag when stored in your car after use, you must smell exhaust fumes comming from the bag.

and this wont work on diesels (exhaust ports on a diesel are much bigger than the funnel)

also will it work on a car with dual exhaust, most dual exhaust cars have a y pipe, so if one port is blocked the the exhaust will just come out the other side

[Kennyredline]

This obviously is not for people who drive POS'...can you imagine being under your car, wondering if it's gonna stall out?? lol:poosie: