New Holland 2120 dead headed pump

[RickB]

I’m concerned about that but uncertain how to advise you.

 

[ptsg]

Check the lines on the power steering valve. Could be that someone tried to rebuilt it and messed up the lines. There should be markings on the valve. A and B goes to the cylinder and P should go to pump and T to tank.

 

[MrTea]

Check the lines on the power steering valve. Could be that someone tried to rebuilt it and messed up the lines. There should be markings on the valve. A and B goes to the cylinder and P should go to pump and T to tank.

Will do thanks.

 

[MrTea]

I’m concerned about that but uncertain how to advise you.

I will verify the lines are in the correct locations as recommended by ptsg then look over the valve in the manual and see if there any clues.

Thanks

 

[MrTea]

Today I took the orbital valve(steering) apart and I may have found the problem. I also don't know what I am looking at really so I could be totally wrong.

Here is a drawing of the valve(I think it's the same)

The relief valve I took off my pump(follow number 2 on the drawing all the way to the left).This is the plug for the hole, the cap to adjust the spring or hold it in place and the spring. According to the drawing there is a piece missing. A plunger looking thing.

It looks like it could have been new or reman.

I put it back together because there was no reason to let it sit in pieces. Now air flows through from the pressure port out the return line. I guess I can put it back on the tractor and see if it steers now. Any other idea?

 

[MrTea]

This is what I think the relief valve looks like in mine. If there is a piece in the bottom of the hole(#3) it does not budge.

 

[mike48130]

I would put compressed air (rubber tipped blow gun) into both pump pressure lines and make sure the circuits are open to sump before starting a new pump.

I would not do this. If there are any particles in the lines, you just blew them into the rest of the system. Take off the lines and clean them. Take out the pressure relief and check it out and the cavity. Spray them all out with brake cleaner.

Put a gauge on the test port when you start it. I would back off the pressure relief so you know it is below spec, then reset it once running and safe. Some reliefs use a screw, some use shims to adjust. Could be set too high or damaged, so a good inspection or replace based on cost.

Check the hydraulic schematics, and check the relief port/tube/galley back to the tank. If that for some reason is blocked, the relief valve doesn't do any good, and won't relieve the pressure. That you can check with air since your tank has a filter on it.

 

[mike48130]

It looks like you are missing the plunger in the relief valve. If that were the case, you wouldn't get any steering even if the pump was working. You would just pump oil back to the tank. Any chance you dropped it by mistake? Could be a rebuilt that was rebuilt wrong.

 

[MrTea]

I would not do this. If there are any particles in the lines, you just blew them into the rest of the system. Take off the lines and clean them. Take out the pressure relief and check it out and the cavity. Spray them all out with brake cleaner.

Put a gauge on the test port when you start it. I would back off the pressure relief so you know it is below spec, then reset it once running and safe. Some reliefs use a screw, some use shims to adjust. Could be set too high or damaged, so a good inspection or replace based on cost.

Check the hydraulic schematics, and check the relief port/tube/galley back to the tank. If that for some reason is blocked, the relief valve doesn't do any good, and won't relieve the pressure. That you can check with air since your tank has a filter on it.

I already checked it with air pressure.
I checked the pressure with a gauge first. There wasn't any because the input shaft on the pump was sheared off.
The orbital valve was blocked.

 

[MrTea]

It looks like you are missing the plunger in the relief valve. If that were the case, you wouldn't get any steering even if the pump was working. You would just pump oil back to the tank. Any chance you dropped it by mistake? Could be a rebuilt that was rebuilt wrong.

I believe the plunger is missing, it would be nice to see a picture of one. I didn't drop it...
I went out to double check and found it on the ground. Dang it. Glad you asked, I had everything laid out as I pulled it apart.I thought there was zero chance I dropped it. Going to put it in and test it with air again.