4440 low standby pressure?

(quoted from post at 12:35:44 07/04/20) Sudden change in system performance. Everything working fine one day, and at some point during the day the three point and all external hydraulics just stop working. Not weak or slow, just quit. Nothing unusual noted. No strange noises, etc. Steering still working fine, no change there at any point.

I found some earlier threads regarding this sort of thing with mention of a priority valve that can/will block flow to these functions if standby pressure falls below a certain point and steering will still be supplied. I have not checked the pressure yet, but will do so soon. Is it likely a drop in standby pressure to that degree could be corrected by a simple adjustment on the pump somewhere? Is it more more likely related to a drop in charge pressure/supply for whatever reason?

Owner is convinced it's a front pump failure of some sort and has I believe ordered a pump and wants me to install it. I have no intention of doing that until I run out of other options.

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(quoted from post at 21:44:55 07/04/20) Try turning the stroke valve screw in (clock wise) to see if the pressure comes up,, they system has a priority valve in the right front corner of the rockshaft, where the pressure oil enters,that will stop the flow to th rear when the pressure dips below 1750psi,, you may have been operating at the brink of this pressure and didn't know it.

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