bottle jack safety question

[Piper]

Hi Everyone

When I use my bottle jacks (all hydraulic not the compressed air type) I jack up the vehicle, then place a jack stand on another suitable load point as a safety. I've always assumed that's the way it should be done safely. Now I'm in the process of purchasing a 4 post lift and am looking at the various models available. A number of them show how, when doing wheels off work that you simply jack that area up and remove the wheel. The thing I find interesting is that I've never seen a jack stand in any of these pictures, simply the bottle jack and wheels off. Am I missing something? Don't all the bottle jack manuals say the jack is for lifting, not keeping the weight there?

Can anyone shed some light on this?

Cameron

 

[bmwpower]

My F250 came with a bottle-type jack from the factory. You place it under the shackle in the front, jack it up and remove the wheel.

 

[Der Bugmeister]

If in doubt, err on the side of safety. Sometimes you only get one chance to learn that lesson...

 

[URY914]

Let common sense be your guide....

 

[astroracer]

Never, ever put your life or limbs on the line with a hydraulic jack! I always put two stands under the car when ever I am changing brakes, shocks or going to be going underneath or have body parts under it. I had a new floor jack blow a seal (the third time I used it) right after I had slid out from under the car. It came down hard and fast and would have crushed my chest if I had still been under it. I learned my lesson the "easy" way and have never forgotten it.
mark

 

[Ryan87LX]

I'll change tires with only a jack, but that's it. NEVER put any piece of your body that you want to keep under a car supported only by a jack. Ever. But you're okay just to change a tire. There is no need to go under. Brakes? no, get a jackstand.

 

[iiibdsiil]

The 4 post lift will stop the car from squishing you if the bottle jack fails. When it's on the ground, the jackstand stops it from squishing you (well, in theory, as the jack is usually take out from under the car and the car is left on the jack stand, but you get my point).

I actually never thought about the jack failing when I've been under a 4 post lift.

Also, if you are looking at a 4 poster, look for the jack that slides in the center. You'll thank me later.

 

[thefairlaneman]

Sometimes the illustrations we see are done just for the camera. As a general rule you always use a jack stand if you plan to place any part of YOUR BODY under the jacked up vehicle. Remmeber even a jack stand can fail if its not level on a solid surface.

 

[kartracer55]

They say its for lifting and not supporting the wait because there is the possibility of failure. When we get walk-ins at work with a flat that they need fixed right then and there I will change it using only a jack because Im not actually getting under the car.

On the 4 post lift, the safest thing would probably be a set of rolling jacks, the kind that slide on tracts between each of the ramps. The ones on Hunter alignment racks have mechanical locks pretty much identical to how a jackstand works. I know other brands do not have locks on these center jacks which is bit dangerous, but if the lift is up in the air you really dont have to worry as much on the ground, right?

Jim

 

[TNToy]

Also, the air jacks built into our drive-on lifts are in a different league, Jim.

When they fail, they don't SLAM to the ground. They come down fast, but they'll give you a good half-second to ****** your hand out of the way. And all of ours have safety stops similar to the 2-post lifts like you mentioned anyway...

 

[thefairlaneman]

Also, the air jacks built into our drive-on lifts are in a different league, Jim.

When they fail, they don't SLAM to the ground. They come down fast, but they'll give you a good half-second to ****** your hand out of the way. And all of ours have safety stops similar to the 2-post lifts like you mentioned anyway...

My first mechanic job used old 2 post floor lifts. I raised a car and placed a stand under the rear end and then went to the parts dep to get something, When I came back the rear lift had leaked down and the back half of the car was supported by a small pole stand,,scared me.........I never did that again