3 point lift noise

[Big_Lug]

I need help diagnosin a noise with the 3 point hitch. I have a Case D40, same thing as TC 40, when I lift the 3 point lever all the way up it cavitates or makes a whinning sound until I let the 3 point lever down about 1-2 inches. Is there an adjustement for this? Can someone post a solution with a picture of the solution. I don't have a manual for the tractor.

 

[jinman]

I think your problem is your position control linkage adjustment. If you look at the picture below, you'll see the area of the adjustment rod. From your description, you need to adjust the control linkage so it is longer than it currently is. That way, your HPL will null out the upward movement before it reaches the physical limit and opens the system relief valve. The whining sound you are hearing is the relief valve lifting.

So disconnect the rod with the tractor off. Start the tractor and raise the 3PH just until the relief valve opens and then drop the lever until the relief valve stops whining. Adjust the rod and clevis until it aligns at this position and one additional turn to make it slightly longer. Reattach everything and check operation. Perform readjustments until the 3PH stops and does not cause the system relief valve to open when the lever is all the way up. You now have the position control lift maximum height adjusted properly.

 

[Big_Lug]

Thank you very much Jihnman, I am off Thursday from work, I will fix it then. I hope the previous owner didn't hurt the pump by making it cavitate like that. Thanks again.

 

[djradz]

Thank you very much Jihnman, I am off Thursday from work, I will fix it then. I hope the previous owner didn't hurt the pump by making it cavitate like that. Thanks again.

Probaly not, it just opens the relief. It does make the pump operate though at the maximum pressure continuosly, so still not a good thing. Not sure if any cavitation results. Kind of like when someone turns their automobile steering wheel all the way (such as when pulling-in/backing-out of a parking space or other tight turn) and holds it there for some short period of time. Not good, but not necessarily all that bad.

One note of clarification on Jim's directions. Jim recommends one additional turn. I'm not sure I'd even go that far, but it is the conservative thing to do. I'm not that concerned about being conservative though with this adjustment as it is very obvious if you haven't turned the rod enough - you'll hear the noise you are already very familiar with. Every extra turn you make results in less lift/heigth you get on your 3-pt lower links. I just turn it far enough so that the relief noise stops and no further. You might have to adjust, test, and adjust again.