3 Point hitch control lever not staying in place

[Mark15]

I recently just finished restoring an old Kubota B20 TBL and am loving it! One pesky problem I haven't been able to solve though is height control lever for the 3 point hitch.

This one has the control style where you set the lever for a certain position, and the implement moves to that position. As you then move the lever up and down anywhere in its range, the 3ph follows, as opposed to the style where the lever has an up / neutral / down position and the neutral holds whatever the current position.

The problem with mine is the lever will not stay where you put it. It feels spring loaded, wanting to always immediately return to the full down position.

The previous owner had tied a string to it with several knots to hold the lever where he wanted it. So far I have been using a dirt bike handle bar-end with a piece of rubber hose jammed into the lever slot to act as a physical position stop. Its a hassle to adjust when working with implements that have lots of up / down operations, and sometimes bounces loose dropping the implement down when the tractor gets bouncy.

I have found some other threads with different models talking about the same issue where they said the fix was to tighten a couple of nuts on the lever shaft to increase the friction / tension. That does not seem to help for mine. I have already tried tightening the 13mm nut as tight as I am comfortable tightening it, and no change on the tension / friction when moving the lever.

The parts diagram shows that that the lever (30) is attached to the shaft (60) with a machined flat. The nut (20) just holds the lever onto the flat and the lever / nut / shaft all move as one piece. The shaft (60) is in turn attached to the internal valve with a roll pin (70).

Does anybody have any experience with these or ideas to try?

 

[North Idaho Wolfman]

If the lever #30 is not separately rotating on #60 shaft then you have an internal issue, like a broken spring.
I would get the WSM before you dive into that kind of repair.

 

[Russell King]

What are the 040 parts? They look like washers and could be Belleville (conical spring) washers. If they are crushed or assembled incorrectly they will not hold the lever in position.
Perhaps remove the lever and see if the shaft will stay in position with nothing attached. It looks like you can adjust the shaft with pliers.


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[100 td]

If the lever #30 is not separately rotating on #60 shaft then you have an internal issue, like a broken spring.
I would get the WSM before you dive into that kind of repair.

Fully read the post this time!

I'm wondering if the feedback rod is a long way out of adjustment?

Or broken roll pin or something else in the control valve is amiss as noted?

 

[Mark15]

Thanks for the feedback guys!

Part 40 is listed as spring washers. But since I think they are located between two parts that seem intended to rotate together, I think they are to keep the fastener tight, rather than to add any friction to the lever movement.

If the lever #30 is not separately rotating on #60 shaft then you have an internal issue, like a broken spring.
I would get the WSM before you dive into that kind of repair.

Thanks! I do have the WSM and have read the teardown / re-assembly for this section and didn't find too much additional information on how this was supposed to work. I will try to get a better close up picture later today, but I do think the lever 30 is designed to rotate with shaft 60. The shaft has two flats machined into it, and the lever has a rectangular hole that press fits onto this. At least I think it does from the illustration! I will try to remove the lever today to verify this. These illustrations are hard to see detail sometimes.

Fully read the post this time!

I'm wondering if the feedback rod is a long way out of adjustment?

Or broken roll pin or something else in the control valve is amiss as noted?

Hmm, hadn't considered that. The operation and position control all seem to work well. Full range of movement at hitch, and no oscillating / hunting when changing height. If only the lever would stay in place when I let go!!

I will check into these and post back. Thanks all!!

 

[Russell King]

Part 40 is listed as spring washers. But since I think they are located between two parts that seem intended to rotate together, I think they are to keep the fastener tight, rather than to add any friction to the lever movement.

I believe these are to provide friction for the lever and should be investigated further.



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[100 td]

The parts diagram shows that that the lever (30) is attached to the shaft (60) with a machined flat. The nut (20) just holds the lever onto the flat and the lever / nut / shaft all move as one piece.

What are the 040 parts? They look like washers and could be Belleville (conical spring) washers. If they are crushed or assembled incorrectly they will not hold the lever in position

I believe these are to provide friction for the lever and should be investigated further.

EDIT: Heads up to Russel King, he's on the money, video of the valve and collar appear to show that the collar floats over the shaft between the handle and housing creating the friction required to hold the lever in place. I was looking at the pressure on the handle from the nut and washer to the shaft.

 

[100 td]

Please see edited post above

 

[Mark15]

I made a short video to help demonstrate how it is currently working. I show how the hitch responds when moving the lever, and then I took apart the lever and showed how the various pieces attach.

I am thinking that the tube collar over the roll pin is supposed to apply some friction against the control valve housing, but everything has worn to the point that the nut tightens against the end of the machined flats before it tightens against the control valve.

https://youtu.be/0cHbdwLNnLE

I think I am going to try to find a washer to add between the control valve and the tube spacer to see if that helps. Let me know if you guys think I am on the wrong track. Thanks!

 

[mbu]

... I am thinking that the tube collar over the roll pin is supposed to apply some friction against the control valve housing, but everything has worn to the point that the nut tightens against the end of the machined flats before it tightens against the control valve. ...

I'm thinking you are correct on this. Tightening the nut on the outboard side of the lever creates the tension not the washers.

Edit...

Just checked on that part which is listed as 67156-36910 - apparently it's discontinued but looks like it could easily be machined. What material is it made of?

Meanwhile... make a test. Cut a piece of leather or gasket material to temporally extend the length of the collar. Then assemble; if it keeps the lever in place you'll know that was the problem. Ace hardware has some nylon washers that may work for this test too.

 

[Mark15]

Well I found a flat washer that fit over the roll pin section of the shaft. I had to cut one side down so that it had clearance for the nut and feedback shaft located below the control shaft. On re-assembly everything tightened up nicely, and I can now add a very controllable amount of friction to the lever when tightening the nut. It seems to work perfect now with the additional washer / shim.

I also noticed in the book that the maximum height position should be set so that you cannot max out the lift cylinder. You could see in my video I was able to lift until the cylinder maxed and the control relief activates. I was always careful not to leave it in this position, but it does make more sense to adjust it so this isn’t even possible. I adjusted the feedback rod length until the full up position on the control lever still leaves about ½” of additional movement at the lifting arms when picking on the lower 3 point arms.
Thanks for the suggestions, I think everything is working as it should now.

Just checked on that part which is listed as 67156-36910 - apparently it's discontinued but looks like it could easily be machined. What material is it made of?

It seemed to be ordinary mild steel. Nylon washers are probably a good idea for a fix as well if you can find them in a large enough diameter.

Thanks!

 

[philruff]

Thanks for the feedback guys!

Part 40 is listed as spring washers. But since I think they are located between two parts that seem intended to rotate together, I think they are to keep the fastener tight, rather than to add any friction to the lever movement.




Thanks! I do have the WSM and have read the teardown / re-assembly for this section and didn't find too much additional information on how this was supposed to work. I will try to get a better close up picture later today, but I do think the lever 30 is designed to rotate with shaft 60. The shaft has two flats machined into it, and the lever has a rectangular hole that press fits onto this. At least I think it does from the illustration! I will try to remove the lever today to verify this. These illustrations are hard to see detail sometimes.



Hmm, hadn't considered that. The operation and position control all seem to work well. Full range of movement at hitch, and no oscillating / hunting when changing height. If only the lever would stay in place when I let go!!

I will check into these and post back. Thanks all!!

I am having the same symptom with my b9200hst. Your post is great,but I am confused which part

Well I found a flat washer that fit over the roll pin section of the shaft. I had to cut one side down so that it had clearance for the nut and feedback shaft located below the control shaft. On re-assembly everything tightened up nicely, and I can now add a very controllable amount of friction to the lever when tightening the nut. It seems to work perfect now with the additional washer / shim.

I also noticed in the book that the maximum height position should be set so that you cannot max out the lift cylinder. You could see in my video I was able to lift until the cylinder maxed and the control relief activates. I was always careful not to leave it in this position, but it does make more sense to adjust it so this isn’t even possible. I adjusted the feedback rod length until the full up position on the control lever still leaves about ½” of additional movement at the lifting arms when picking on the lower 3 point arms.
Thanks for the suggestions, I think everything is working as it should now.



It seemed to be ordinary mild steel. Nylon washers are probably a good idea for a fix as well if you can find them in a large enough diameter.

Thanks!

I am having the same symptom with my b9200hst. Your post is great,but I am confused which washer was added, even with the picture. If you could add some words of wisdom, I would greatly appreciate it!