I purchased the JD 410 backhoe from the auction awhile back and have just got around to running it. The hydraulics seem to be staying loaded ( full work pressure). It's more apparent the longer you run the machine. Once is cutoff and you try to crank it you have to open a valve for the outrigger,boom,etc. So the motor will turn over freely and not stall. Any ideas on what the problem is?
That's the way they are. What do you mean by " It's more apparent the longer you run the machine" ? Does it lug at idle with no hydraulics operated? that would mean you have a leak. Some had a destroke solenoid to let it start easier, which model exactly, or a pic of the hydraulic pump with any wires might help.
If all controls are centered, I would suspect a blown seal in the control valve body. This allows oil to bypass and deadhead that circuit.