Rear 3PH is not working - running into a wall

[CaptPat]

I had this issue, turns out it was the third-function valve, the switch was defective causing the valve to be open all the time. The third function was "robbing" all of the hydraulic pressure from the 3-pt. The mechanic knew exactly what the issue was when I described the symptoms. Replaced the switch and everything works as expected.

 

[rScotty]

I had this issue, turns out it was the third-function valve, the switch was defective causing the valve to be open all the time. The third function was "robbing" all of the hydraulic pressure from the 3-pt. The mechanic knew exactly what the issue was when I described the symptoms. Replaced the switch and everything works as expected.

 

[rScotty]

Regardless of brand, the open center hydraulic system is used by most manufacturers. All of these open center tractor hydraulics work about the same. That's good, it makes diagnosing them easier.

They do not need to be bled, and there is no special provision for doing so. The sump (return tank) is open to the atmosphere and the hydraulic system is self-bleeding.

Since the power steering and FEL work, there should be pressure at the power beyond port on the control valve manifold. My first guess is that the "sleeve" that OldnSlo mentions in post #10 slipped out and was lost. The purpose of the sleeve is that it blocks extra flow from going to the return post and instead directs it to the power beyond port.

So those sleeves are always there - they have to be there - when power beyond the FEL manifold is used. You may want to take off the hose to that port and make sure the sleeve is stiil there. Sometimes the sleeve screws in, other ones just press in.

On it's way from the PB port to the 3pt and rear BH remotes (if there are any), the fluid goes past a solenoid for 3rd function accessories (front remotes), just as CaptPat says in post #11.
I would sure check that solenoid as well. It is capable of robbing all the flow. Normally, that solenoid will not have any flow diveted to it's return line to the sump.

A simple pressure test kit makes testing all of this easy. Inexpensive. Amazon and others have them.


rScotty

 

[arcteryx]

Are any of the connections marked on the valve? Seems like there is no standard in how that power beyond port is labeled though. In most cases it is on the opposite end from pressure but again not always. This should go back and supply oil to the 3 point valve and rear remote valves if you have them.

Some valves have a “special” fitting sometimes called a sleeve that goes into valve to create power beyond others just have an internal plug. If the fitting or sleeve style it will usually have a taller hex than a standard fitting.

I will have to clean the FEL valve and see. Here are my connections though, there is one on the side that is not shown. None are a quick connect that I can tell. I labeled 1 and 2 when I replaced the hoses for the FEL.

 

[arcteryx]

I had this issue, turns out it was the third-function valve, the switch was defective causing the valve to be open all the time. The third function was "robbing" all of the hydraulic pressure from the 3-pt. The mechanic knew exactly what the issue was when I described the symptoms. Replaced the switch and everything works as expected.

Assuming you mean rear remotes, I don’t have a third-function.

 

[arcteryx]

Since the power steering and FEL work, there should be pressure at the power beyond port on the control valve manifold. My first guess is that the "sleeve" that OldnSlo mentions in post #10 slipped out and was lost. The purpose of the sleeve is that it blocks extra flow from going to the return post and instead directs it to the power beyond port.

So those sleeves are always there - they have to be there - when power beyond the FEL manifold is used. You may want to take off the hose to that port and make sure the sleeve is stiil there. Sometimes the sleeve screws in, other ones just press in.

On it's way from the PB port to the 3pt and rear BH remotes (if there are any), the fluid goes past a solenoid for 3rd function accessories (front remotes), just as CaptPat says in post #11.
I would sure check that solenoid as well. It is capable of robbing all the flow. Normally, that solenoid will not have any flow diveted to it's return line to the sump.

A simple pressure test kit makes testing all of this easy. Inexpensive. Amazon and others have them.

Thanks for this. Where is this sleeve? Is this on the manifold or on the control valve (#21 below), which requires disconnecting the lines and removing the manifold. And to complicate things, the parts diagrams do not have a breakdown of the control valve but the manual does. I am guessing that they replace the control valve entirely and not the valves n bits themselves.

Here is the parts diagram I was able to get. They don’t make it easy to copy/paste links.

https://johndeere.widen.net/content/p5mnf9xpzo/jpeg/0003156839____________A1.jpeg?w=1900&h=1900

And what would be my PB port? Would it be labeled?

 

[oldnslo]

What does the line with the blue zip tie connect too? It is the line in picture 5282 with the long hex fitting two connections above hose labeled 1. That style of talk hex is sometimes an indicator that it is a power beyond sleeve. I can’t tell if line next to it has same style fitting or not.

 

[CaptPat]

Assuming you mean rear remotes, I don’t have a third-function.

The 3-pt is last in line to receive hydraulic press/flow, if anything before that is loading the system the 3-pt may not work. In my case, the 3rd-function valve was the culprit, either flow to the 3-pt is blocked/bypassed or something else is consuming hydraulic service. Since you have the tech man I'd trace the various hydraulic lines to verify proper installation, it's easy enough do and would rule out actions by a previous owner/maintainer. It may also be worth teeing a pressure gauge to verify that your pump is putting out rated pressure and flow.

 

[arcteryx]

OK here are the lines and where they go. Which of these would be the PB port? - EDIT- I don’t have PB

The blue zip tie is a loader hose up front.

The 2 metal lines underneath go to the 2 ports close to each other on the manifold.

The hose on the side of the FEL valve goes to the port at the bottom of the transaxle.

On the manifold, the one on the lower right bottom goes to the transmission. This is Item H on the hydraulic oil line schematic.

There are 2 smaller lines on top of the manifold as the photos show. The one on the left side goes to the piston under the seat, the one on the right side appears to be a return line and enter the top of the transmission/transaxle.

Lastly, here are 2 schematics from the my Deere manual. I don’t have a Bleeder Valve (G), although here is a hex cap. And where H would be on here, there is not a side quick connect

Hope this helps

 

[oldnslo]

Page 70-30 -2 shows item H as implement pump to rock shaft valve supply so if my interpretation is correct line H would be connected to power beyond line from FEL to rock shaft valve which is 3 point hitch.

This is based on that diagram on page 70-30-2 not including an FEL valve.