FEL Diagnosis

[Egon]

Put a load in the bucket and lift. Also see what happens when you try to something withe three point that is heavier than what it is rated for??

 

[winston1]

What about this is risky?

I really don't think anything is risky about this on your 240. I really believe your relief valve would take care of any pressure once the stop valve is closed. Some models, not sure which can be over pressured and crash the pump when closing the stop valve. I am just not confident enough in my knowledge not to warn anyone to be careful.

Try this test. 1. Put the 3 point handle all the way down (lowered). 2. Close the stop valve. 3. Very slowly begin raising the 3 point handle watching the gage. You should see pressure rise to 2200 lbs and relief valve go off. No more comment until you try this and report findings. Might have to get engine higher than idle to achieve this.

 

[woolyAcres]

What about this is risky?
Try this test. 1. Put the 3 point handle all the way down (lowered). 2. Close the stop valve. 3. Very slowly begin raising the 3 point handle watching the gage. You should see pressure rise to 2200 lbs and relief valve go off. No more comment until you try this and report findings. Might have to get engine higher than idle to achieve this.

So here's what happens. With the 3 point all the way down and the loader on the ground, I closed the stop valve. With engine RPM at about 2000 I began raising the loader. Loader goes up like it should and pressure runs about 800psi. Same as before. When it hits the top and can no longer extend, pressure jumps to about 1000psi.

I know you didn't suggest doing this next part but...

With the stop valve closed I very gently and slowly tried to raise the 3PT. Almost immediately the pressure jumped to 2200 and I could hear the pressure relief valve on the rear. So, as long as my little test didn't damage the pump, I think my pump is ok. And my conclusion from all this is that the loader relief is set to ~1000psi. There are problems with the loader valve not working the curl correctly, but I'm done worrying about that. The valve is getting replaced. I also think the pump is good. What I don't understand is why there is pressure in the system when the 3pt is up but not moving. Based on that drawing in post #6 it seems like the system should pressurize to raise it but once it's up where it belongs it should not need pressure. It might pulse once in a while to bring it back into position.

 

[woolyAcres]

Put a load in the bucket and lift. Also see what happens when you try to something withe three point that is heavier than what it is rated for??

With a load in the bucket greater than the tractor can handle pressure goes up to ~1000psi. Unfortunately I don't have anything too heavy for the rear. I think this box blade is the heaviest thing that will fit my cat1 hitch. I've got a cat2 back blade but that won't attach.

 

[winston1]

So here's what happens. With the 3 point all the way down and the loader on the ground, I closed the stop valve. With engine RPM at about 2000 I began raising the loader. Loader goes up like it should and pressure runs about 800psi. Same as before. When it hits the top and can no longer extend, pressure jumps to about 1000psi.

I know you didn't suggest doing this next part but...

With the stop valve closed I very gently and slowly tried to raise the 3PT. Almost immediately the pressure jumped to 2200 and I could hear the pressure relief valve on the rear. So, as long as my little test didn't damage the pump, I think my pump is ok. And my conclusion from all this is that the loader relief is set to ~1000psi. There are problems with the loader valve not working the curl correctly, but I'm done worrying about that. The valve is getting replaced. I also think the pump is good. What I don't understand is why there is pressure in the system when the 3pt is up but not moving. Based on that drawing in post #6 it seems like the system should pressurize to raise it but once it's up where it belongs it should not need pressure. It might pulse once in a while to bring it back into position.

I thought that was what I suggested. In my opinion you have proved your pump is good and your 3 point relief valve is good. Would you be against upping the relief valve pressure on your loader valve?

I went back to your original thread and looked at pictures of your loader valve. Couldn't find any picture showing the location of your relief valve. Just guessing it will be behind a cap nut on the front of the valve, toward the radiator.

As to why your 3 point is holding backpressure. With the loader setting on the ground does it read the same 1000psi. That is with the 3 point in the up position or maybe just a tad down from all the way up.

 

[clemsonfor]

They say pumps rarely go bad. Only ones I think we seen here were dead headed? Even aaron at hour and those guys rarely suspect pumps there just that rare to go.

 

[clemsonfor]

I think there is pressure when its up but not moving to hold it up. Cut tractor off with it in air and see how long it holds up. The pressure may be to hold it up?

 

[woolyAcres]

I thought that was what I suggested.

Indeed you did. I simply mis-read what you wrote.

 

[Leejohn]

Check the feed back rod and make sure it is working right and not binding. That should let the oil dump to tank when it gets to where you set the lever and the 1000psi should go away. Also check the spring in the loader relief valve, could be broken or the valve is stuck open a little.When you get the 2000psi it might be because the gpm is greater then what the relief valve can dump.

 

[woolyAcres]

I thought that was what I suggested. In my opinion you have proved your pump is good and your 3 point relief valve is good. Would you be against upping the relief valve pressure on your loader valve?

No. I've got no objection to trying that. But because the loader valve has other problems (curl function, lacks float, etc) I'm replacing it regardless.

I went back to your original thread and looked at pictures of your loader valve. Couldn't find any picture showing the location of your relief valve. Just guessing it will be behind a cap nut on the front of the valve, toward the radiator.

The only (possibly) useful photo I have of the control valve is below. There look to be a couple 'plugs' on one side. Maybe that set screw is under one of these.

As to why your 3 point is holding backpressure. With the loader setting on the ground does it read the same 1000psi. That is with the 3 point in the up position or maybe just a tad down from all the way up.

When the loader is on the ground, and the 3 point is anywhere but on the ground, it reads 1000psi. It will drop down if I lower the 3 point just a bit. It almost seems as if there's something sticking that holds open a valve which allows pressure to build up. I think LeeJohn might be onto something. I'll have to look at the linkage tomorrow (ran out of daylight today). Maybe something there is bound up and preventing it from returning as it should.