View Full Version : floor jack question.

Mr Fixit
11-01-2013, 11:23 PM
Went to my brothers house today to move a car I had stored there. I tryed to use his floor jack and the darn thing would hardly raise anything up. It seems like it just had no fluid to pump. My question is I have a quart of hydralic fluid but I've never filled a floor jack before, how do you do this job?
The jack is a 2TON generic brand maybe even Harbor Freight. I saw what looks like a fill screw next to the raise lower wheel of the handle is this for the hydralic fluid?

TX in advance I will watch for your responses.
Mr fixit for the family
Chris :)

11-01-2013, 11:43 PM

Most any fluid will work in a hydraulic jack so don't run off for special stuff. I would open the little fill port and add fluid while jacking the thing up. The secret is to add juice until the jack is at full extension, leave the fill port open and lower the jack slowly. Fluid will barf out of the fill port until the jack is fully lowered. When it's fully lowered, screw the fill plug back in and you should be good to go. That's my take on this thing!!!


11-02-2013, 12:22 AM
Sometimes when a hydraulic jack does not hold a load properly or it goes up slowly with what seems like only half effective strokes, it may need to have the air bled out of the system.
First though, do make sure that the jack has the required amount of oil.

There are several ways to bleed the air, but I find this the easiest way to bleed air out of the jack and it always works for me with both horizontal and vertical jacks.

Open the release valve fully open, at least two full turns. Now with the release valve still open, pump the jack handle about 15-20 strokes. That's it you're done! Close the release valve and give it a try.
Occasionally I may have to repeat this procedure one more time, but most times once is enough.
Horizontal jacks usually pick up a little air from being stored vertically and vertical jacks pick it up from being in a horizontal position.

11-02-2013, 12:32 AM
Il have to remember that one, i binned a jack for the same reason, it could have needed a bleed, new dog old tricks lol

11-02-2013, 09:34 AM
If not low on fluid or air bound, the cause will be bad pump or ram seals. The seals will eventually fail from wear on the best of jacks, but the cheap imports seem to suffer from that quite early.

11-02-2013, 09:59 AM
If the jack needs fluid go and buy some jack oil any auto part store should sell it. Jack oil is less then 10 weight and none detergent. Any other fluids or oil will cause problem and for god sakes stay away from transmission fluid

A.K. Boomer
11-02-2013, 10:10 AM
there is also adjustments for pre-load on the check valves...

I had to "jack" with mine because im at altitude and had to lighten up the check valve so it had enough draw to suck in new fluid on the return stroke...

If your jack is a horror freight it should have a rubber access plug on top of the big cylinder... this is where you add...

what a great jack - mine was 49 bucks about 25 years ago and is still going strong, mine leaks but it's from losing the plug and having to use a pen top instead...
iv ran everything from jack oil to power steering fluid to ATF, things still going strong and can't kill it,,, it's outlasted about 4 or 5 of my buddies snap-ons and at close to ten times the price apiece that's really chapped his hide...

11-02-2013, 02:46 PM
Before doing all the above, just check that the valve control is closing the valve properly! My FIL had a 2 year old 2 ton floor jack that wouldn't lift, the type with the valve control on the end of the handle, and the gears were jamming slightly, so the valve never actually turned fully closed and the jack would not lift. If you lowered the handle slightly, the gears meshed properly again, and the valve closed, and the jack worked perfectly. He was going to dump it!!!