L3400 3-point hitch adjustment

[LD1]

First move is to set the "spool joint to plate" adjustment to spec, it is 1 mm over the manual recommendations now. I think the only effect that will have is the lift will raise to a higher or lower spot in relation to the scale on the lever bracket, which will necessitate a re-adjustment of the feedback linkage.

I'd save yourself the hastle because you are correct....all that does is set the implement to lever relationship. But changes nothing about how the valve operacts/acts.

When I first measured mine, I was shocked that it was 50.5mm instead of the spec of 47.5:confused2: But upon looking closely I seen it would do NOTHING to adjust it......but I did anyway, and set it to 47.5mm. The result was the implemet started to lift MUCH sooner. And ran out of travel too quick so I had to adjust the feedback rod per their direction. By adjusting until the relief kicks is, and then backing out two full turns. (or 2.5). I could have left it that way and no one would have been the wiser, BUT....I was out fo adjustment in the feedback rod. There are only 2" or so of thread for adjustment. So I put it back where it was @ 50.5mm and that left the "correct" feedback adjustment centered right in the middle of the threads.

With yours only being 1mm out, you probabally wouldnt need much feedback adjustment, but it really isnt worth the hastle knowing it wont help the situation at all.

PS...I hope you arent using RTV sealent everytime either. I found out quickly that I wasnt going to take the time to clean/seal everyting until I had it where I wanted it. I probabally had that top cover on/off at least 10 times. The onlything I re-assembled for testing whas the cover, banjo/hydraulic line, and the two plugs (PTO and N saftey??). I used a pin in place of the lever to test, and just heald the gear selector switch with my other hand. After the second time, I got tire of putting too much back together.

Good Luck once again.

 

[Chilly807]

I'll be at mine again shortly. I only used the sealant on final re-assembly, it doesn't leak much since there's no pressure at the top of the case.

Sean

 

[Chilly807]

I got it apart again, and tried tweaking the distance between the spool joint and plate to 47.5 mm, exactly in the middle of the specified range. As we expected, all that did was change the arm position in relation to the control lever. And the original setting, although out of spec according to the manual, puts the feedback nut almost dead center in the adjustment range. Strike one.

Next was the set screw adjustment to 0.033" gap. The hitch still hunted up and down by itself, although very slowly. Strike two.

Next I adjusted the set screw gap to 0.036", and although it didn't hunt, it was sensitive to any weight added to the hitch, namely me standing on the drawbar. It would edge up slightly, then settle and repeat after a few seconds. Also, instead of a jerk when raising, it was almost a chatter, several small increments. I'd planned to get it stable, then add about 0.003"-0.004" for insurance. It's hard enough to get apart that I don't want something that's going to be temperamental over temperature changes, slight wear, etc.
Adding 0.004" to probably 0.038" (to get it to a stable point) puts me back at 0.042", only 0.003" away from what it was when I started this project. Strike three...

I adjusted back to 0.045" and put it back together with sealant. I'll try it tomorrow, but I should have exactly what I had when I started, which although less than ideal is live-able.

I hope you guys have better success than LD1 and I did. I see now why Kubota wants no part of fiddling with these. I'd love to leave it at 0.006" gap as it was in the video I posted, it is simply super-smooth and controllable. However, I think the settling then jumping back when you use upstream hydraulics is worse than the rough raise I had before, and I still don't know for sure that it won't damage the valve long-term.

The results I got mirror LD1's for the most part. I may do some more research to see which valve is in the L3010, and what differences there are between them, but I plan to leave mine as is at least for the short term.

Sean

 

[sadie72]

Good news here, I think. Just got my L3800 back from my dealer with a smooth operating 3ph. Dealer and Kubota regional service rep took my valve apart yesterday and found it was not set to the appropriate suggested factory settings. I was told they made one adjustment and put it back together to find decent results. I am totally pleased with the performance of the vertical motion at extremely slow lever speed. I did notice that when curling and uncurling the FEL bucket the 3pt does lower about an inch and then goes back to original height after bucket curl. I personally don't feel this will hinder my intended use of the FEL and 3ph as I don't normally use both at the same time.

I asked my dealer what specifically was adjusted, what the original dimensions were and ultimately what it is set to now. He didn't have the numbers with him, but the Kubota rep wrote everything down. I should be provided with this data soon. Will keep you posted.

If I knew how to post a video, I would. Can someone help me with this? I have video of before and after on my iphone.

 

[LD1]

The results I got mirror LD1's for the most part. I may do some more research to see which valve is in the L3010, and what differences there are between them, but I plan to leave mine as is at least for the short term.

Sean

And you even have the newer valve and couldnt get it to work. Boy I'd sure love to hear from one of these dealers that "supposedly" adjusts them to spec and they magically work:confused2:

Good news here, I think. Just got my L3800 back from my dealer with a smooth operating 3ph. Dealer and Kubota regional service rep took my valve apart yesterday and found it was not set to the appropriate suggested factory settings. I was told they made one adjustment and put it back together to find decent results. I am totally pleased with the performance of the vertical motion at extremely slow lever speed. I did notice that when curling and uncurling the FEL bucket the 3pt does lower about an inch and then goes back to original height after bucket curl. I personally don't feel this will hinder my intended use of the FEL and 3ph as I don't normally use both at the same time.

I know you say you dont use the FEL and 3PH at the same time, BUT what you describe is the dynamic pressure situation that Sean and Myself had due to an overlap in valve timing. And (at least on mine) was RPM sensitive as well.

And (if you are like me) change rpm while using the 3PH at times.

So let me ask you to try this:

But your back blade (or even a mower on)....And then lower it to where it is "not quite on the ground" with the tractor at an idle. Now go to full rev and see if it moves.

Because like you, I though I could live with it because I dont use the 3PH and loader at the same time. UNTIL I found out it was RPM sensitive as well. And with my blade ~1" off the ground, (pretending like I was grading and would have put it in gear and reved up), the blade raised up ~3-4". ANd then when I let off the gas (like slowing to make a turn or gear change) the blade lowered again. THIS was unacceptable.

So....see if yours is sensitive to RPM change.

 

[sadie72]

Will try this tomorrow, for sure.

 

[sadie72]

Probably doesn't matter whether you have HST or gear, right? My HST tractor 3ph did not seem to move when I rev'd up from idle earlier this evening. But I'll pay more attention to this tomorrow and get back to you.

Are you suggesting the dynamic pressure condition could wear the valve out prematurely? I better get something from my dealer in writing about their adjustment for after the warranty period...

 

[teg]

...was just surfing the net and ran across this statement, thought I would throw it out for any comments?

"...Unfortunately this is not any easy adjustment as the top of the HST must be removed to gain access to the valve. The valve then needs to be removed to be adjusted, (via shims or springs, not sure at this time) then placed back into the tractor then tested..."

 

[teg]

...the reason the L series has this problem is the 3-point design is flawed somehow...

Just in case you missed this thread. http://www.tractorbynet.com/forums/...21524-l-series-jerky-3-point.html#post2537561

 

[teg]

Did someone want to look up the valve *I THINK* I got: It might be the valve from an L3010 Grand L, part # 31351-39604 but I never saw it or got any paper work to confirm this. Sorry, that's the best I can do.