Thanks for the input, I think you nailed it. There’s two o rings and a rubber hose about 4” long to compensate for movement between engine and reservoir it’s directly below the engine oil filter and over the years and oil changes I suspect it’s brittle. It’s up and running and I’ve ordered...
Changed hydraulic oil and pump would not pick it up. Disconnected front loader lines disconnected backhoe lines to eliminate the possibility of those lines possibly sucking air. Still nothing, it took cracking two small bolts on the pump to get the pump to clear the air and start moving oil...