OK Gentlemen, With Manual in hand and a nice sunny weekend to tinker, here's what we've got.
The easiest relief valve to check is the Combi System Relief and Diverter Valve. It appears to be OK after removal and inspection. I did however encounter a small bit of metal debris about the size of a large grain or two of sand when I cleaned it out. I'm beginning to suspect some kind of contamination and blockage in the Relief valve(s) located within the 3 PT. system. Any relief valves that are within the 3 Pt. Assy. will have to be checked by the dealer as I just don't feel comfortable opening her up without a garage to keep out of inclement weather not to mention this would really test my mechanical aptitude.
In my flow tests, I got 15 OZ. of fluid from the power beyond hose and 9 OZ. from one of the FEL hoses. I have to keep in mind that the Power Beyond Hose is twice as thick as one of the FEL hoses. It appeared to be quite easy to stop the flow from the Power Beyond Hose. So I've got flow but no pressure.
In the Troubleshooting section of the manual, I looked for common points between "Implement fails to lift" and "Implement rises to slowly". They are as follows:
1. Bad Saftey Valve
2. Bad Hyd. Pump
3. Oil Leak Past Lift Cycl.
4. Restricted Suction Folter
5. Control Valve Plunger Stuck Open
6. Lowering Valve Spool out of Adjustment.
Non Common Points include:
1. Linkage Adjustment
2. Relief Valve Setting Too Low
3. O Ring Failure at Valve Body to Cover
4. Bad Relief Valve.
With that in mind, I think we can eliminate a Bad Hyd. Pump as the FEL works just fine (Can lift a full bucket of sand/Dirt etc...There is no suction filter in the 1920, only the 2120, eliminating that cause. Control Valve Plunger Stuck open doesn't ring true as I can control the rate of 3Pt. arm descent with the control valve. That leaves 1, 3 and 6. I would also include potential blockage in the Hyd.Control Valve and/or the Flow Cntrl.Valve, both of which are contained within the 3Pt. Housing Assy.
At this point, and after discussing with the NH shop last Thursday, I will bring the tractor down to the shop and let them take it from here. They'll charge me $61/Hr. and are just as stumped on this as we all are so they've taken this as somewhat of a challenge. Perhaps they'll go easy on my checkbook but I need to get it fixed.
Any thoughts at this point?
Todd in Placerville