L3400 3-point hitch adjustment

[Chilly807]

Chilly,
I have a 2007 year L3400 but I haven't noticed and issues with mine and I think if it were as bad as your "before" video it would be obvious. Do you know if this problem is with gear shift tractors only or HST as well?

Great thread and great information! I have saved the link to my favorites in case I ever need it! I applaud you for taking the time to take photos and post. The good info keeps streaming from TBN.

Internet.....what a great invention. Thanks Al Gore.

Some are better than others, no one mentions they have an issue with a smooth hitch, I guess.

The part that got me interested in working on mine was some have actually been fixed although the process was a little cloudy.

Sean

 

[Chilly807]

Mine is 2010 Hydro, and it is a spitting image of chilly's "before" video. It has the later model of valve. I wish it looked like his "after" video

James K0UA

I think your's will be every bit as good as mine is now, James, once the dealer has a chance to get in there and re-set the valve. That's the only thing I did with mine. If he's open to questions, ask him if they have any kind of a service bulletin on this issue, or if they are just going to use the workshop manual for the specs.

What I'm curious about is whether there are different procedures for the latest valves, and where the serial numbers cut off one procedure from another. What is the serial number of your machine, incidentally?

Sean

 

[Chilly807]

Unbelievable! Great work Sean. Thank you.

Do we all feel this is the same issue with the L3800 model? Do they use the same type valve? I just purchased a L3800 which exhibits the same jerky vertical motion at slower lever movement. NOT acceptable for a normally high quality Kubota product. To be frank, I'm tired of hearing from Kubota that I should have bought a Grand L.

Is the adjustment procedure the same for a L3800 as Sean details so nicely on his L3400?

I think it is the same issue, the L3800 is an updated version of the L3400 to some extent. I tried an L3800 on the dealer's lot a few months ago, it was the same as mine to a slightly lesser extent.

A lot of owners never consider it a problem depending on their use, but I'm just **** enough to insist on it working as I think it should. Using a grading blade is tricky.

My dealer has been very supportive about helping me research this and find a solution, short of tearing into it themselves. I think if they had known how to fix it, they would have done it for me already. Taking apart a customer's tractor in the blind hope of finding a problem with no corporate support isn't good business practice, although it does show the customer that they are willing to do what it takes to keep him as a client.

You'd have to get into the WSM for the L3200/L3800 to be sure about specifics, they could be different. Probably not, but no guarantees.

Like I said earlier, I can't even be sure I haven't changed something I'm going to regret in a few months to the tune of big $$. It's a calculated risk to assume Kubota has a "human error factor" that's been causing this problem. In my experience, the Japanese don't make many mistakes when it comes to machinery.

Sean

 

[Slimson]

Fantastic write-up!
I was just reading through my WSM last night wondering if these adjustments would help on my L3200 and now I know.
I just re-checked my WSM, and the L3200/3800 adjustment dimensions are the same.
The parts manual I have shows a P/N YR908-00105.
The jerkiness on mine is somewhere between Sean's before and after video with a rotary cutter on back. So far been more of an annoyance than a problem. But now I feel better to know when I get the time, I will be able to fix it.

 

[LD1]

The issue with the "settling" wouldnt be an issue for me at all. Honestly, if not mentioned and I did the "fix", I would probabally be clueless, because I always lower the implement before turning the tractor off:thumbsup:

 

[Chilly807]

Fantastic write-up!
I was just reading through my WSM last night wondering if these adjustments would help on my L3200 and now I know.
I just re-checked my WSM, and the L3200/3800 adjustment dimensions are the same.
The parts manual I have shows a P/N YR908-00105.
The jerkiness on mine is somewhere between Sean's before and after video with a rotary cutter on back. So far been more of an annoyance than a problem. But now I feel better to know when I get the time, I will be able to fix it.

Great information to add! Each of us has a tiny piece of the puzzle tucked away whether we realize it or not.

Your finding the same dimensions in your WSM clears up any confusion as to whether Kubota had changed the setup with the newer style valves and tractor models, apparently they haven't.

Sean

 

[Harvest Moon]

Just to note, many of the parts on the L3400/L3700/L3800 etc. line came from previous versions of L's/grand L's including at least some of the valve model variants. And they may still be used on models outside of the L line.

Maybe it's an administrative mistake. The valves may be manufactured to settings matching their original or alternate uses and when they are pulled from inventory for the L3400 assembly, the assembly steps as defined by Kubota may overlook resetting the valves to the Engineer/WSM settings developed for the L3400 family.

For concerns of long term problems associated with making these adjustments, I'd guess there won't be any. It's not an experiment so much as just meeting the OEM specs. - better than the OEM.

 

[smweatherman]

Just to add to the discussion. I have a 2010 MX4700. It has the jerkiness with valve YR908-00104. I have the WSM for the MX4700/5100 and it gives the dimensions 16.0-16.3mm for the plate to valve, and .1-.2mm for the set screw to poppet clearance.

Same-same it looks to me.

 

[Chilly807]

I got a chance to give it a good try today clearing snow with a rear blade.

The good news is it's still silky smooth on the raise stroke.

The bad news is I discovered that if you use hydraulics other than the 3-point, the load settles as it does when you shut the engine off, then when you release the lever for the loader or rear remote, the hitch snaps back to the original position.

What's happening is that with the valve in neutral position, it's using hydraulic power to maintain that position, when you take power away from it by using other hydraulics upstream of the 3-point valve, it drops as if the engine was shut off. This is what I suspected, that there was still flow to and through the valve in a steady state position.

It only drops about an inch, but it's noticeable. The heavier the implement, the worse the shock load is going to be.

I can't say as I'm happy with this "side effect", in fact it means I'll be digging into it again and trying some more adjustments to try and get rid of or at least reduce this problem. If I can't, I'll be going back to the factory settings, to me it's worse than the rough hitch movement.

If I reduce the gap from 0.045" to maybe 0.040" or 0.035" I should be able to reduce the amount the hitch jerks without getting into the "hunting" up and down I was seeing at 0.030". I doubt it'll be as smooth as it is at the WSM settings, but I can live with some compromise.

I'll post the results as I get a chance to make changes.

Sean

 

[k0ua]

Oh, no!... keep us posted.

James K0UA