NAA hydraulics

[loafersglory]

I have a Ford Golden Jubilee tractor. Recently I rebuilt the 3 point hydraulics. Tested after installation everything was working properly until the unit ceased to lift. Hydraulic pressure had tanked (was 1200 - 1500 PSI) at plug on top of unit. A visual inspection revealed fluid leaking from safety/relief valve on piston lift cylinder. I replaced valve and now have no pressure on gauge. I want to know if I have the proper replacement part (see photos)? The shaft end of the new valve is beveled where the shaft the old one is concave. Does the check ball have to be removed to use new valve? Any information would be appreciated. Thanks

 

[Leejohn]

Sure looks like it would not take much to unseat the new valve. I would say it's not the right replacement.