Do you have any hyd flow at all?
If you have flow and raise the 3pt, does anything work.
If you try and raise the loader, does anything work?
If you have a 3000 psi hyd gage, install it in a tee in the IN/input port of the FEL valve.
If you hold the lever on the FEL full fwd, does the relief valve activate, and if so, the pump is working at the set relief pressure. and the trouble lies elsewhere.