The hydraulics on my free lift cylinder are acting goofy. The free lift does not go up, instead the outer stages go up. When I took the cylinder apart there seemed to be a vacuum on the bottom of the cylinder, so I had to release the pressure by taking off the hydraulic lines to take it apart. I cleaned everything up put it back together and it worked fine for a little while, but went back to doing the same thing. I am stumped, any help would be appreciated.