3-Point Hitch Deere 670 3PH issue

[bamamarine]

I've got an early 90s 670 that has been sitting in a barn for a couple years. Everything was working fine when it was parked. It runs good now, but after sitting the 3ph has zero movement. The arms move freely by hand, and the pump is moving fluid. Screen is clean as well. Is there a likely culprit such as a frozen relief valve in the system?

 

[DLTTrekkers]

air in suctionhose ?
loosen pressurehose....start engine bleed air out !

 

[bamamarine]

I pulled one of the aux plugs and fired the tractor up and it shot a solid stream out. I don't think there's an air issue in the feed or pressure lines.