3-Point Hitch Another L3700 with Jerky lift

[InThePines]

Ok, I have read the threads on this and it seems a problem was corrected years back on L3400. I have even watched the video and seen what it was like. I have a new L3700 with 19 hours. Fast and moderate lift speeds are fine, but when I try to do small position adjustments for a box blade for example, it gets pretty jerky. FEL is smooth. Is this something I just need to accept or should I press my dealer? I have better luck lifting fast and lowering slowly than trying to lift in small increments.
Thanks for your advice.

 

[SmallTimeCountry]

My 3700 does the same thing. I'll be interested in hearing what others have to say about this.

 

[Code54]

Very true, mine is anything but smooth also.... Nice machine and really this is one thing they should work on a bit. let us know what you fine out of yo press it

 

[ritschner]

What is the setting of the three point lowering speed knob? If the setting were all the way open for high speed lowering and there was any play in the control lever linkage, it seems it might cause the jerkiness described.:confused3: It might be worth a try adjusting the setting. Otherwise it may be the adjustment of the three point system itself.

 

[montelatici]

What is the setting of the three point lowering speed knob? If the setting were all the way open for high speed lowering and there was any play in the control lever linkage, it seems it might cause the jerkiness described.:confused3: It might be worth a try adjusting the setting. Otherwise it may be the adjustment of the three point system itself.

I don't have a jerky 3-point the brush hog but I keep the lowering speed knob on a very slow setting.

 

[InThePines]

I don't have a jerky 3-point the brush hog but I keep the lowering speed knob on a very slow setting.

Thanks for that advice. I tried it just now, and I still have the problem when lifting. I have tried different settings on that speed knob and it does slow the release, but does not help with the lift. I hate to trailer it up.....

 

[Harvest Moon]

I've tried to solve this problem with my L3400 but have had limited success. My machine was among the early machines offered with a basic position control valve. The only known fix was to upgrade to a better valve, which I did. It improved things but it's still not smooth.

Later versions of the L3400 included the upgraded valve standard. But then there were reports of another valve change, and for some it seemed a step backwards towards the earlier valves performance.

It appears that the hydraulic cylinder used in the L3400 is too small for the flow rate delivered by the valves, which were originally used in earlier pre L3400 model tractors with larger cylinders.

The L3700, likely has the best of the L3400 valves but also likely has a higher flow rate than the L3400 and therefor is likely even jerkier. I'd love to see a video, there are several posted of the L3400 with different valves. It would be interesting to compare.

When I bought my tractor, it was marked as a "standard tractor." When I sought help, I was told: Sorry, you bought an "economy" tractor. Worse now, the L3700 is marked as an "economy" tractor. So, best of luck to you all.

 

[montelatici]

I've tried to solve this problem with my L3400 but have had limited success. My machine was among the early machines offered with a basic position control valve. The only known fix was to upgrade to a better valve, which I did. It improved things but it's still not smooth.

Later versions of the L3400 included the upgraded valve standard. But then there were reports of another valve change, and for some it seemed a step backwards towards the earlier valves performance.

It appears that the hydraulic cylinder used in the L3400 is too small for the flow rate delivered by the valves, which were originally used in earlier pre L3400 model tractors with larger cylinders.

The L3700, likely has the best of the L3400 valves but also likely has a higher flow rate than the L3400 and therefor is likely even jerkier. I'd love to see a video, there are several posted of the L3400 with different valves. It would be interesting to compare.

When I bought my tractor, it was marked as a "standard tractor." When I sought help, I was told: Sorry, you bought an "economy" tractor. Worse now, the L3700 is marked as an "economy" tractor. So, best of luck to you all.

Actually the term is "Special Utility", hence the SU nomenclature. :laughing:

 

[ccsial]

When I got my 05 L3400 the 3PH would jump about 1 inch at a time. The dealer changed the valve and it now jumps just a bit under 1/4". It made a big difference in being jerky but it is not as smooth as my ford.

I would suggest putting a ruler or stick back there and measure the jump increment while very slowy raising the control lever. If you are getting about 1/4" I doubt there is anything Kubota can do for you.

 

[k0ua]

Here is what I have found, on my 2010 L3400:
If you raise the lift, in one smooth movement, no problem it will go there smoothly, you then can lower the lift by gently moving the lever down in any increments you like, and it will smoothly go down. However if you "overshoot" the place you want to stop at. you cannot just nudge it back up a little it will jerk up every time. so to summarize: move up to one position, in one movement of the lever, no problem smooth movement up to that position and stop. And to move down smoothly, no problem, you can move in one or multiple movements of the lever, and the movement is smooth. BUT if you try to move up in small increments, Big potential problem, jerky upward movement.
Overall this has not really diminished anything I do with the tractor, I just know how it works and I work accordingly. But is is not smooth up with small movements. YMMV
James K0UA