I asked this question once before and about the only advice I got was 
to buy a new one.  Strange advice from a group that lives and dies by 
keeping very old cars on the road.

Anyway, I have a borrowed 2 1/4 ton chinese made floor jack.  It works
fine for about two inches.  After that it moves up in very small 
increments.  At least it used to.  I cracked open the big screw thing 
on the back and was met with some fluid and bubbles.  Figuring I was 
onto something I proceeded to try to fill this hole with some jack 
fluid from the local FLAPS.  I tipped the thing up on end and every 
way possible but couldn't get any more into there.  Now the jack works
even less than it used to.  So, how do you fill your jack when it is 
low on fluid?  There is another screw on there (smaller).  A similar 
jack at the FLAPS had tags saying not to touch this screw for fear of 
inflaming the gods of jacks.  I can only guess what it does.  Please 
help, I need this jack to work so I can put my shiny new motor in 
soon.  Thanks, Jim
-- 
James A. Brill Jr.         \\  //
jbrill@unlinfo.unl.edu   \\ \\// //      If you're not outraged
University of Nebraska    \\//\\//     you're not paying attention.
free-lance homo sapien     \/  \/