Ford 3910 hydraulic problem

[Growin]

Ford 3910 loader and 3pt work but are jerking lifting.The selector valve has 3 positions (pic added). Lifts loader and 3pt in normal position only. New filer and correct universal oil. When selector is forward to normal the loader and 3pt operate as described and when loader reaches maximum height the valve kicks into middle position, same thing when bucket goes all the way up. Putting the valve in rear, drop position the loader will not move either direction but when valve pushed back to normal the loader will reach maximum height with no issues until valve kicks to center position. Will lift 750lbs cattle panel easily and does not fade. Hydraulic pressure reads around 2600psi on drop position but does not hold. In normal position there is no reading on gage. I am testing from the lift port of the valve. Any opinions in this issue?

 

[MRTOES]

Sounds like pressure relief valve sticking

 

[Harry in Ky]

You're only providing part of the story. The valve you pictured is a single spool remote valve(which we must assume) supplies a loader valve of some sort? Said loader valve can only operate correctly when this valve is supplying flow to the "in" port of that valve. If this is a hydraulically detented valve it WILL cancel to neutral when pressure in the loader circuit reaches max for that portion of the system. All that seems normal to me. As for the "jerking" lifting that could be from different reasons. Low or restricted oil supply, hydraulic filter needs replacement, something on that order.