Alright, so its not mine. Guy got it with bad engine put one in, got it running. To find out ps and lift don't work. He took both hoses off front of the charge pump while running nothing really comes out. Puts his finger over the ports and doesn't feel any pressure built up. Both relief valves are up. Says it has fluid in it
You may know this but I will mention it just in case. Under the seat pan those two valves with the little “buttons” on them are often referred to as “free wheel” valves. When you use the lever to depress them it lets you “put the tractor in neutral” so to speak so you can easily push the tractor.
I can't imagine why you say there are three pumps...only one charge pump and one hydrostatic (variable displacement) pump show in the documentation. There is another symbol in the lower part of the diagram, but that is the hydraulic motor that drives the differential to the wheels.
I did watch the MRRBEEF video and he admits in the audio track that he may not be using the factory terminology, so maybe that is the origin of the three-pump confusion.
Here are the names of the numbered items in the diagram:
The P port of the hydro unit is the pressure side out to the steering and the hydraulic accessory ports on the tractor, while the R port is the return to the system reservoir. The axle motor and the various relief valves return to the reservoir directly... The TM1590 has a good legend of what each symbol means if you need to noodle out the various valves.
For the tractor to move under its own power, but have no steering or aux port pressure, the "charge relief valve", which is #5 in the diagram, and/or the "implement relief valve - #6" must be stuck open.
The relief valves only have an effect on the motor driving the axle, and will not be part of the symptom you have been describing in this thread.
EDIT: This is to address the question in post #5 of this thread -- yes a failed pin in the charge pump could also be the reason to have no steering or aux port power and still have tractor motion...I did not realize that the pin was not eliminated as a possible cause this far down in the thread when I made my post/description here.
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