Pluming for a loader valve on a 5205 john deere w/553 loader

[386 captain]

I am installing a loader valve on a 5205 JD w/553 loader. Loader originally plumbed through rear remotes. I am installing a 2 spool loader valve that matches hydraulic specs. My question is will I have to run a line from the valve power beyond back to the tractor selective valve on the right side of tractor? Valve has 3 plugs, one is marked R. Pressure. One marked S return, and other one I assume is PB, don't see markings , looking at 5205 manual, does not indicate what it is for. Loader valve has port, pressure inlet, and port for outlet. My question is will I have to run a line from power beyond valve back to selective valve on side of tractor? Any info greatly appreciated. The 5205 is open center.

 

[Tx Jim]

I think you can operate the FEL valve without attaching the PBY port to tractor but I'm old school hyd knowledge. Back in the 70's-80's I attached several OC spool valve to OC hyd tractors with no PBY port on spool valve. BUT this is how hyd valve is plumbed in the 553 FEL PC

 

[J_J]

Most valves with PB come with the PB plugged. Main passage fluid and cyl fluid will exit the OUT port and go to the next valve. There is the potential to damage the valve due to back pressure.

I think I would use a 3000 psi hyd gage and find which plug/port had pressure.

If he already has remotes, and an external hose, he could remove the IN hose from the remote valve and run it into to the IN port of the loader valve.

The PB port with PB adapter hose would go back to the remote valve.

The return/out hose connects to another return hose.