Having problems with twin telescope jacks. The jack on the right works great. When I run the car the jack on the left side only pushes out the big cylinder until you get high enough and it hits it's stop ring. The small cylinder pushes out if you continue to run the car. Once you stop running the car the small cylinder sinks back in until it's collapsed back into the bigger cylinder. The small one doesn't seem to hold the pressure in. I have no leaks, bled the jack a thousand times,the jack seemail to always havery air in it, changed the seals in it twice, even tried syncing the jacks a bunch a times also. I'm at a loss. Checked the piping in the pit also, piping is even feeding both Jack's at the same time. Any help is appriciated.