1952-59 Ford power steering over heating

Hey, Big Dave from Tn. I have a 59 Ford with power steering. Out of the blue the system has started overheating. I put a kit in the pump, the control valve, and a shaft seal in the cylinder 4000 miles ago. It steers great but the fluid is boiling hot. Start up cold and let it idle and in 10 minutes the reservoir and control valve are hot to the touch. Did not check the temp of the cylinder. I have also changed the filter again. Pump feels good turning by hand. Any input would be helpful. Thanks

 

sounds like a restriction somewhere in the system.