Floor Jack Question

[Tony G]

I have a hydraulic floor jack that works well and doesn't even leak down. The problem is that it wont raise from the fully retracted position. If I lift up the saddle pad slightly and advance the piston it starts working fine. I have bled it
as best I can. No leaks either.Does anyone have any suggestions?

 

[Rookie2]

maybe:
http://www.garagejournal.com/forum/showthread.php?t=197787

 

[Hiball]

Possibility of weak pump seals that can't overcome the vacuum, a overly full reservoir will amplify the affect on a sealed system. It's possible that lifting the arm is creating enough cylinder vacuum to aid in pulling oil, with that said, lifting the arm is ingesting air into the system. Maybe try removing the fill plug, and see if that remedies the situation.

 

[Tony G]

Thanks Hiball, I'll try t.