If you’ve ever been caught needing a jack and not having one—or having one not up to the job—you know the results can be frustrating, even dangerous. A good hydraulic jack can be the best tool for safely lifting heavy objects while you work on them.
This small floor jack is 18 inches long and weight 18 pounds. Pro-LifT
Hydraulic jacks come in two basic types—bottle jacks and floor jacks. In a nutshell, hydraulic jacks use pump plungers to move oil through two cylinders. When the plunger is first drawn back with a lift of the handle, it opens the suction valve ball within and draws oil into the pump chamber. As the plunger is pushed forward with a downward press of the handle, the oil moves through an external discharge check valve into the cylinder chamber, and the suction valve closes, which results in pressure building within the cylinder and pushing the jack up. Bottle jacks take up less room to store and use, so excel when jacking up an object in small places. They typically lift smaller loads, up to about 6 tons. Floor jacks are bulkier, harder to store and require plenty of room around whatever object you need to lift. But they are safe and easy to use, and large ones can lift several tons.
This large bottle jack can lift loads weighing up to 1,200 pounds. Big Red
The weight of the object(s) you want to lift with your jack will make a big difference in your selection. Study all the pertinent information available on jacks that you are considering. If you’re going to be lifting an 8-ton truck, never consider a jack with a weight limit of 5 or 6 tons. It’s always better to err on the high side when choosing a jack. A jack that will lift more will usually be heavier and harder to stow, but you’ll be glad you have it when you need to lift a really heavy object and have the capacity to do so.
This floor jack will lift a load to a height of 18 1/8 inches. Arcan
The height to which you need to lift an object is also an important consideration when choosing a hydraulic jack. To find the right jack, compare the number of strokes and maximum height for each hydraulic jack you are considering. In order to do that, check the number of steps the piston has: The more there are, the higher each stroke will lift the jack. If you need to lift something higher than your jack will accommodate, some manufacturers sell extensions that enable you to lift objects even higher than the jack’s normal maximum height.