Hi The valve under neath is flow the one on top is the relief, it should be held with lock wire, what have you done with that one because if that's not right it won't build pressure either. I have seen a few of those flow valves come out twice before they worked.It could be the flow valv seat is damaged in the block to, Thing is i'm guessing a lot of this, seeing it all is something i'm dissadvantaged heavily with here.
The Front levers will have neutral in the middle on 1,2and 4. meaning right forward is float next back would be external power one way then neutral, right back would be power other way Make sure those are all in neutral, I think that might affect flow in the block, as you can't use 2 functions together on older tractors. 3 is the one that should go right forward and then back 2 clicks if my books right. You should then be able to raise lower the 3 point, with the position lever by the seat or under the steering wheel depending where it's located on a 530. Just out of interest does the pto work to power an implement?. The hyd pump drive comes off the back of the clutch cover. I have seen a few where the splines wear, but not right off normally to loose drive, the 66 series internationals do this. Then they loose pump drive and pto. I wonder if that could be your problem here also as you say seems like no pump drive. if it is that it's a pretty big job as the front of the trans has to come apart to do it. all my customers so far have said just change the clutch cover and hope it lasts a few more years , before it strips, had one go home like that last week!. Regards Robert