[MustGoFaster]

Probably has air in it I have never taken one apart, but I don't think there are any seals that are going to have issues with being upside down. As for fixing it, try pumping it all the way up and letting it down a couple times. (bleed the air out maybe) Also, when it’s all the way up, see how far you can pull it down. Erik D might be a good guy to talk too, he does hydraulics too. And i believe he even had a job fixing them (jacks) at one point.