Hitachi Zx55u-5A Clr hydraulic schmatic

Hi all, I'm after a technical manual for a Hitachi ZX55U-5A. The machine is running really slow on everything and I'd like to check how the LS system is set up on it. Has anyone run into this before? When I disconnect the LS line from the control valve, nothing comes out whether the levers are moved or sitting still—there's just no flow at all.

The control valve inlet section on the ZX55U-5A is the same as a Deere 50G. I'd check whether the orifice (item #23) is plugged, and also look at the inlet strainer (item #10) if needed. The PLS oil goes through the orifice before it exits at port 41 to the delivery flow rate valve on the pump.

I've got the ZX55U-5A hydraulic schematic here.