Wayne County Hose said:
I can double check and I don't know about the PT, but if memory serves me correctly, these valves are ORB threads. You could troubleshoot a valve by screwing in an ORB fitting with a cap (or an orb plug) and running the machine. The ORB fitting would allow fluid flow straight thru and just act as a plug. I'll doublecheck tomorrow, I just thought of this.
Andy,
I am thinking that you would have to put a plug in two holes to force fluid through the block to the PTO block, Here is why, I believe this is an open center valve, and the fluid goes to the input and out to the tank when the solenoid is not activated, so by plugging the solenoid opening, the fluid would still go out to the tank, unless that opening was plugged. The output to tank flow also takes care of any relief fluid.
I still say put a gage on the output of the PTO block, and activate the PTO switch, and if pressure builds up to 3200 psi, then the pump is good, and the solenoid block is good. Nothing should be plugged into the PTO hoses for this test. If you activate the PTO switch and get little or no pressure, then the pump is bad, or the solenoid plunger is hanging up, or the solenoid is not pulling or pushing the plunger, which closes off an orifice and open another. By the way, is this a spring loaded plunger? Spring might be broke or weak.
You could also bypass the PTO block completely by connecting a hose to the hose from the pump, then to a gage and shut off valve, and run the output back to tank. Start the engine, and slowly close the shut off valve, but not all the way. Never close the valve all the way, something will blow up. Watch the pressure on the gage. If the pump is good, the gage will show the pressure based upon how far you turn the valve.
Like Andy said, manifold blocks generally don't go bad, just the internal parts.