[Davey10]

What seal or O-ring goes bad that would cause the hydraulic lift arms to creep down and raise up constantly on an a 1958 Oliver 550 gas tractor?

 

[Davey10]

Anyone?

 

[TUDOR]

I've thought about your problem and the only thing that I can come up with is broken or corroded centering springs in the control valve that allow the spool to hunt back and forth.

Remover the cover on the back of the valve for a look see and some housecleaning. Maybe pull the spool for an o-ring change as well.

It is a control valve problem for fluid to cycle a cylinder back and forth like that.

 

[Davey10]

Ohh ok thank you! That makes a lot of sense. I will check it out today!