Repair 7

How to Rebuild Bottle Jacks

Although many of todays jacks are designed to be disposable and replaced as soon as they break, you can still rebuild some jacks to get them working like new again. If you can find a repair kit for your jack, then you will be able to tear down the jack, replace all the seals and then rebuild it again. All jacks vary, so you may find you are able to pick up the O-rings outside of a kit although this may result in a less-than-perfect seal.

Instructions

1

Drain the oil from the jack into a pan by removing the oil filler plug and draining the oil through it. Remove the filler plug and put it aside. Remove the handle assembly by unbolting it and put it aside. The bolts you have to use will vary depending on the jack you are working with. Once the handle assembly is off, pull out the pump. This may require you to hold the jack in a vice.

2

Remove the release valve by unscrewing it. In some cases this will require a wrench, the size of which will depend on your jack. Remove the overload valve, which is next to the release valve. This is a screw as well. Be careful since inside are two small balls with two springs. Make sure you recall the order in which the balls were removed. Place the balls and the springs aside.

3

Use the pipe wrench to remove the tank nut, which is at the top of the jacks bottle. Pull out each part individually and take careful note of which goes inside which. If your rebuild kit came with instructions, then you may be able to use it for notes.

4

Examine all the O-rings and seals for cuts, dents, pinches or other damage. Your rebuild kit should tell you which to replace. If you are working without a rebuild kit, then take any damaged O-rings to your local parts store and replace them with new, identical ones.

5

Reassemble the piston by sliding the parts back inside each other in the opposite order in which they were removed. Replace the piston inside the bottle and tighten the tank nut with the pipe wrench.

6

Replace the balls and springs inside the overload valve in the order you removed them. This is usually the smallest ball, followed by the smaller spring, followed by the larger ball and the larger spring. Depending on the jack, you may have extra dividers or hammers. Replace the screw in the top of the overload valve.

7

Replace the release valve by replacing the ball and then putting the bolt back in place on top.

8

Replace the handle assembly by sliding the piston into place and replacing all the bolts holding the mounting assembly in place.

9

Refill the jack with oil and check for leaks. Wipe down the outside with a cloth. Bleed air from the jack by opening the release valve and pumping vigorously several times. Close the release valve and pump the jack to its full height, Open the release valve and let it retract again. If it does not reach its full height, then check the outside for an oil leak and repeat the process until it does. If there is a leak, it may reveal a badly installed seal.

10

Test the jack on a vehicle. Check the outside for any leaks caused by the extra weight you are lifting.