If we were talking about damage to a suction hose, yes, that would be a concern. But on a pressure hose or delivery, any damage not leaking is inconsequential to our troubleshooting. If your pump is in good order, the pump shop said you were good. Their job is to sell you stuff. Why would they fudge when they could make a buck? Let's look at your relief valves. Has anyone, to your knowledge, adjusted them? Are the jam-nuts tight? It's hard to believe that could be the issue, but we can't rule it out.I had another play around tonight on the digger and this is what I found.
this might be a little tricky to understand but I’ll try my best. Okay so I have 3 outlets coming from the pump, P1,P2,P3. We won’t worry about P3 because that goes to the solenoid block. So P1 and P2 both go to the valve block and each side is for left joystick and right joystick, as you know my machine just doesn’t work properly and acts like there is no pressure but at full revs I can get a little bit of control from the left side but nothing from the right side, it won’t even lift the boom. I switched over the hoses tonight and at full revs I can now lift the arm (obviously not quick or how it’s supposed to function) and I haven’t been able to lift it before this. In comparison now the other side controls hardly work. I did notice I have quite a few wear through marks on the (bad) hose/side but no leaking and the horrible vibration/cavitation sound is following the (bad) hose. So I’m not sure if it is the hose or if the pump is just stuffed