One line not working 3rd functional FEL valve ???

[vanoverp]

Hello all.

I have a Kubota L3400 with a 3rd function hydraulic valve (installed at dealer) on the front end loader. I use it for a grapple. I am having a strange problem.

I can open the grapple, but something is wrong, and I can't close it. It has worked perfect for over a year until now. I had this same problem recently, but I let the pressure out of the line by loosening the coupling. The grapple closed and I tightened the fitting back down. It worked fine after that.

Today the same thing happened again. I opened the grapple, but then I couldn't close it. I don't hear any noise from the pump when I click the thumb button on the joystick. Could this be the pump motor or some type of switch? I have no clue about this stuff.... I really hope I don't need a new motor. If I do, I hope it is under warranty, because the tractor is just under two years old.

Any thoughts? Thanks a bunch!

Paul

 

[mjncad]

Welcome Vanoverp. I'm guessing the thumb switch is bad, or the solenoid on the diverter valve is shot, or both.

Hopefully KennyD will spot this thread as he knows his hydraulics way better than I do.

 

[kennyd]

Welcome to TBN Paul

Relax, your pump is fine as is your switch and valve. I suspect your problem is what is called "regen" or the "regenerative" function of the FEL joystick valve.

Can you please tell me exactly how you operate the grapple? And what kind of switch you have? (is it a momentary switch or does it have 3 positions?) Pictures would help also. I need to know what type of valve you have so I can help you further...

 

[vanoverp]

Thanks so much for the help. I don't have pictures right now, but I can take them when I get home.

The switch is what I would call a 3-way switch, but I could be wrong. You can press it to the left (to open the grapple) and press it to the right to close the grapple. If you don't press it, it centers itself back to the middle position. Does that help?

How would I would be able to find out what type of valve I have? I know nothing about this stuff, so I really appreciate the help!!!

Paul

 

[kennyd]

Thanks so much for the help. I don't have pictures right now, but I can take them when I get home.

The switch is what I would call a 3-way switch, but I could be wrong. You can press it to the left (to open the grapple) and press it to the right to close the grapple. If you don't press it, it centers itself back to the middle position. Does that help?

How would I would be able to find out what type of valve I have? I know nothing about this stuff, so I really appreciate the help!!!

Paul

Great info Paul, That's what I need needed. You have whats called a "3rd function valve" or a "solenoid operated spool valve"

Scratch what I said about regen-that is not your problem...

You will need a volt-meter to diagnose further, you will have to check and see if you have power to the solenoid when the switch is moved Left or Right.

Since the problem is intermittent, I suspect you have a loose connection between the switch and a the valve.

 

[vanoverp]

Well, the rain has settled in here for the day and I can't get outside and do anything, but I will definitely try. I saw two wires that lead to the little motor that operates the 3rd function valve. I guess I have to check each right? Like, ground my voltmeter to the frame and check one wire with the switch pressed one way, and then check the other with the switch pressed the other way?

I will try this and let you know, but I will wait to see if that is what you meant. I appreciate your help big time... My tractor is not under warranty so this is great help..

 

[kennyd]

Well, the rain has settled in here for the day and I can't get outside and do anything, but I will definitely try. I saw two wires that lead to the little motor that operates the 3rd function valve. I guess I have to check each right? Like, ground my voltmeter to the frame and check one wire with the switch pressed one way, and then check the other with the switch pressed the other way?

I will try this and let you know, but I will wait to see if that is what you meant. I appreciate your help big time... My tractor is not under warranty so this is great help..

Yes, that is correct. Not sure what your solenoid looks like so I cannot pinpoint any better.

If it's like THIS one, then one end of the solenoid will have power for one way and the other end will have power for the other way-did that make any sense at all

You can also use the OHM or continuity mode to check the wiring (with the power OFF) from the switch (if you have access) to the solenoid. ALSO check all the grounds-thats the leading cause of intermittent problems.


Oh, and one other thing just to make sure it's electrical...when the grapple fails to close-does the engine bog down at all?

 

[vanoverp]

no, it really doesn't look like that at all, but it could just be because it is mounted up and down on the tractor, not flat.

When the rain stopped a minute ago, I went out and found some writing on it. It had LONS on the top of it. Does that help any? To answer your question, when the thumb button is pushed, the engine does not change at all, it doesn't make a single noise... There are two wires that come out of it and they are taped up and run up and underneath the loader joystick housing.

I am going to research that name LONS and see what I can find...

 

[vanoverp]

D03S-2B-12D-35 - Solenoid Directional Control Valve

I found this valve (link above) and it looks very close to the one on my tractor. Don't know if that helps, but I thought I would throw that in.

 

[vanoverp]

I found it. I didn't realize the LONS was actually LONG, and it is the brand of grapple that I have. Here is the link that shows the valve and control switch:

Valve Kits