December 23, 2019

Care and feeding of Hydraulic Jacks

As the video above shows, the problem may just be air. So push the piston all the way down, leave the valve open, top off with oil, cycle the jack while holding the piston down and you are done. Pushing the piston down and holding it down forces all the air out of the "lift piston".

Rebuild kits with O-rings and seals can sometimes be found for name brand jacks. As for replacing the rubber plugs, I will note that the 50 year old Blackhawk jack had a metal plug in a threaded hole. I like that.

The one critical thing that is not shown in the diagram below is the release valve. It generally provides a "bypass" path from the lift cylinder back to the fluid reservoir.

Have any comments? Questions? Drop me a line!

Tom's Auto repair pages / tom@mmto.org