Floor jack valve

[dd5]

I've got this old Sears 2 ton just about figured out. Turning the handle feeds the square core down on a ball bearing. Is that bearing supposed to seal against the metal seat below? There is no O-ring down there (or in exploded view diagrams I've seen). That seat appears to be a solid part of the body, i.e. not a moving piece.

What am I missing here? The release valve isn't holding and there are no leaks anywhere.

 

[5ubtle]

You might get better responses here if you can post pictures, exploded diagrams, schematics, etc.

*If* I understand what you are asking; yes, the ball bearing and it's seat form a valve (the ball seals against the seat).

By "The release valve isn't holding", do you mean that the ram won't stay up when loaded?

 

[dd5]

The ram fails to lift the jack. Unloaded it goes up, but If I put 160lbs (me) on it, it goes down.

I know tubing flare fittings form a metal to metal seal, but much softer metals. I think I'll try an O-ring down there.