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Hydraulic Jack Parts

Hydraulic jacks are rugged tools that can lift cars, trucks and even houses. There are a couple of things that can go wrong that will cause the jack to fail and that the average do-it-yourselfer can fix on their own at home.

Why your hydraulic floor jack won’t lift

One issue that can occur is air getting mixed into the hydraulic oil. A second issue could crop up when you have an internal or external oil leak. Both of these issues will prevent a necessary pressure buildup that the hydraulic system requires to lift items up.

How to fix your jack

Removing the air from the hydraulic system is fairly easy. All you have to do is refill the reservoir with hydraulic jack oil. Do not use motor oil, brake or transmission fluids in the reservoir. These types of oils can harm the internal parts of the cylinder, with a few exceptions. You should check the manufacturer’s specifications if you are unsure about what type of oil to use.

Find and open the oil filler port and pour fluid into the jack. You need to make sure you only open the port filler and not the cap for the overload valve. The overload valve is a safety feature, and it stops the jack from exceeding its PSI limit. Once the oil cap is off, pump the jack handle a couple of times to push the air out, and then fill the reservoir with new oil.

Fixing a leak often requires taking apart the cylinder to get at the internal parts. These parts include

  • O-rings—The O-rings are used to provide a seal between the piston and other internal parts and the wall of the cylinder. This helps keep the fluids from leaking out of the cylinder and air from getting into it.
  • Ram—A ram is a shaft that comes out of the cylinder and pushes up when you pump the jack.
  • Gland nut—The gland nut is screwed on over the open end of the cylinder where the ram comes out. The gland nut is used to secure the seals and any type of packing that is used inside the cylinder.
  • Neoprene seal—A neoprene seal is used to keep impurities from getting into the cylinder.
  • Seals and gaskets—There are a few different types of seals and gaskets used in the cylinders of hydraulic jacks.

Get what you need at Sears PartsDirect

You don’t have to search all over for parts for hydraulic jacks. Sears PartsDirect has all the parts you need for Companion, Craftsman and Test Rite hydraulic jacks. At Sears PartsDirect, we care about you and can answer any questions you have on how to fix your hydraulic jack.