Make sure you are running the PTO near 500-540rpm. Big difference in pump pressure when running slower than rated PTO speed. Aside from that, my guess is your control valve unit needs to be rebuilt.
Also, FYI, in my experience with #30 ejectors, if you run the ejector over 6 to get heavy bales (60+ lb) into the wagon, you are going to break the H frame at the pivot point (most have already broken and show the typical welds and re-welds). So, once you get things running normally, be careful when using the higher numbers on the control valve with heavy bales. 6 should be plenty to throw 45-50lb bales over the back of an 18ft wagon if the ejector is working properly at 500+ PTO speed.