Help floor jack problem

I have a powerbuilt 2.5 ton floor jack from kragen that won't lift anymore because the little hydraulic nub you push down on with the lever doesn't return back up so I can pump again. When I take a screw driver and pull the nub back up, I pump the jack again and the nub stays down.

If I pull the jack straight up from the lift point, it hold pressure just fine and stays up all the way. And there is no leaking oil from what I can see. The jack is completely filled with oil too.

Any help would be appreciated on helping to get this jack working

sounds like an internal valve went bad... had the same happen to me. hope you were planing on upgrading soon...

i guess i am now.

if i remember right powerbuilt has a lifetime no questions asked return policy. i have broken numerous powerbuilt sockets/ screwdrivers/wreches etc. and i just take em back to checker orielys and the switch it for a new one no questions asked.

^ if they are anything like craftsman, something like a jack wont have a lifetime warrenty

your probably right. but i figure its worth a shot. and i think its a limited lifetime. seals and stuff wouldnt be covered but a valve might be.