Loss of multi function

[TheOldHokie]

Good call putting a gauge on it. That pretty much clears the relief valve and the pump, so I'd stop chasing pressure. Since it only quits once the grapple bottoms out, I'd look at flow. When the grapple cylinder dead-heads, that circuit sits at relief, and how the diverter is teed into the lift circuit decides whether curl still gets oil. I'd also make sure that new return line is fully seated,

There is no diverter. Its multiple valves in series. The grapple is a solenoid operated 4 way valve fed by loader PB. When the grapple is in motion return oil from cylinders is being fed to next valve via neutral (T port). When grapple stalls oil flow to next valve is blocked as is the upstream (loader) neutral.

Dan