You are putting a lot of words into the thread that don’t answer the question of exactly how it is currently hooked up.
Could you make a sketch and take a picture of that and post it? That would make it plain how it is or was hooked up, since you also seem to be making changes fairly quickly.
Just slow down and think of it as flow through one hose to another hose with valves that only divert the flow when they are activated.
The (potential) pressure from the pump should be able to get into each valve (P) and then out of that valve (PB or sometimes T) and go to the next valve. If you are capping of that flow the pump can deadhead unless it has some pressure relief in place. You can see that in your diagram you posted above.
I think you can simplify the system to eliminate anything except the loader and 3PH but you don’t need to if you know it worked in the past when arranged in exactly the same manner as it is now.
And are you saying that you have moved four complete quick couplers (eight pieces) around on the loader and the problem did not follow the sets? I am unclear on that. I know you moved male connectors and female connectors around but not 100% sure what you did so perhaps post pictures of what you moved around. Most of these problems seem to be solved by replacing a coupler that is defective is why I am asking you about these again.
Sorry I didn't answer earlier - I missed your post.
Here is the problem: Initially the loader would not lower when the control stick was pushed forward. It would rise, but jerky. This problem started as an intermittent malfunction that has steadily gotten worse. Now pushing the stick forward raises the arms. Curl and dump work fine. Float function also fine. This problem started independent of any change in the hydraulics setup. All was working until it started not to work.
Here is what I have done:
1. Switched the female ends of the quick connects to the loader on the spool valve - A to A and B to B. The problem followed the side of the spool valve; was with arms then shifted to bucket. Switched them back.
2. Switched the male ends in the same manner with the same result. Left them switched.
3. Removed the spool valve and had it inspected by a mobile mechanic who also had it examined by a hydraulics shop. No problem was found by either one although they could not see the internal passages. They made the suggestion the monoblock may have as crack that is widening with time. They advised a new $1070 (+ tax & del) spool valve.
4. At some point I disconnected the power beyond to my WR Long 3rd func controller. That made no difference and it's reconnected now.
5. The 3-point hitch is not connected to an implement because my BH77 backhoe is mounted , but initially it was in the full up position. Lowering it made no difference.
6. Although I have read many times that loader function problems are almost always not the control valve, with the opinions from mobile mechanic and hydraulic shop I put in an order for a new FEL valve then started posting hoping Dan would jump in and show how they were wrong and I could cancel the order. He has tried and may yet guide me to a solution so I can cancel the order.
