Just to clarify, and thank you for the help BTW
I have a guage T'd in right after the pump. When I raise the arms with load, I have a load on the pump, usually around 1k psi. This pressure seems to be from the valve, as I have shut the lock valve eliminating the hyd lift cyl and the pressure on the pump stays the same.
The check valve in the 3ph control valve seems to be good on the new control, as the load stays up after the engine is killed.
Without the 3ph in the hydraulic circut, loader valve output to tranny directly, there is 0 psi.
I can see how the ports attached after the check valve in the 3ph control will show the load, but I'm seeing it at the pump all the time. This could be normal, but I haven't found anybody with a guage T'd in on a Yanny yet to know for sure.
The control linkage seems simple, a feedback arm is attached to the main lift arms which rotates to pull back the block pushing the 3ph control shaft in.
I was thinking that after the load is at the desired height, that the 3ph valve would shut off flow to the main lift cyl. and pass the pump flow to the resevoir, thereby having no load on the pump. However, if the nuetral positon of the valve still involves the use of the internal check valve of the 3ph control, I see why I would see the relief pressure all the time.
The Yanmar pumps have no internal relief valve, but there are Orings and pressure bypass ports to relieve pressure from spots internal. I worry about the temp getting too high and damaging those o rings. The pressure relief valve is in the hydraulic cyl. head of the lift and is the standard spring/steel ball deal.
If I'm rambling, its because this has been a long fight started by a weak pump. I then plumped the infernal pressure guage in which is like giving a stethoscope to a hypochondriac.
Jerry