3-Point Hitch L-series Jerky 3PH - Jeff's homebrew repair.

KiotiLK35 · Nov 28, 2013

Thanks to all you guys who responded to my question, particularly thanks to J252 for providing all the details in an illustrative and understandable manner. Seems to me the plumbing on my Kioti is very similar to the L3400 so should be a parallel fix. Will check it out in more detail today and start shopping around for an appropriate flow control valve.

Can I ask one more detail question?. if the main hydro pump capacity is 7.88 GPM what would ideal spec of the flow control valve be?

Here's where I really miss living in the States (we lived in Portland, Or from 2000-2003) - shopping! You guys have access to so much MORE stuff for such LOW prices! Oh well, I guess thats the price we pay in Oz to live in a big place with a small population.

KiotiLK35 · Nov 30, 2013

Can I ask J252 …. did installation of the pressure compensated flow control valve actually remove the jerkiness of 3PH, or did it just reduce the effect? I watched the video and the lift motion looked pretty good after the mods, but I never got to see the "before" version. Also I notice in the video you are moving the lift lever pretty swiftly. Does it make difference of you just inch the control lever up slowly? That's when I get the worst jerky response on my Kioti LK35. If I move the lift ever through it's full ark swiftly I get a much smoother lift action (no jerking) but then I have gone from ground level to full height, which I often do not want to do.
Either way your mod seems to be much better than my current situation. I just want to be as fully informed as possible before I start any mods. Realistic expectations and all that crap.

smweatherman · Nov 30, 2013

Hi KiotiLK35
Wish you well on your attempt to improve your tractor. You might be interested in the thread at http://www.tractorbynet.com/forums/kubota-owning-operating/268927-mx5100-jerky-3pt-hitch.html as well, especially beginning around post #112. I had/have jerky 3pt issues on my MX4700 and installed a flow control valve to alleviate some of the issues.

Best of luck

KiotiLK35 · Dec 1, 2013

Many thanks Weatherman. I read suggested posts and watched your video. Great to see behaviour at different flow settings. I am relieved to see that this problem is quite common. I thought it was just coz I had purchased an "economy" Kioti model. I would be mighty peeved if I had sprung the extra $ to replace my old Kubota with a new Kubota and discovered the same problem with the new Kubota. My old (mid 70's L245) was as smooth as glass in 3PH operation. Having read and viewed Jeff's home-brew thread I can see that the approach is tried and trusted so I am convinced that it is the best option for me to pursue. My local Kioti dealer didn't even know my model (LK35) existed (even though factory manuals are titled LK30/35) so I am very glad I didn't invest too much time trying to get them to resolve the problem while the tractor was still under warranty. I did visit them when they have a brand new DS35 in the yard (seems to have replaced LK35 in 2012) and we tested 3PH operation on the lot. EXACTLY the same jerky behaviour as mine - no surprise. So now I need to shop around for the requisite pressure compensated flow control valve. Looks like the 8 GPM valve from Surplus Centre that Jeff refers to would suit me well (LK35 output is 7.8 GPM). My frustration is that down here in Oz the local dealers want around $350 for a similar valve, whereas you guys can get them for about $80. Having lived in the USA for a few years that really gets up my nose, but I guess thats the price of choosing to live in a BIG country with a small population! Will set about getting shipping quotes from Surplus Centre or Princess Auto to ship to Australia. Seems to me I would still come out ahead! Anyway, thanks for the response and for improving my understanding of the problem. I now feel a lot more confident about what to do. My only challenge is to confirm how the plumbing translates to my LK35. Unlike your tractor (and Jeff's) it looks to me like all 3 lines to/from my FEL are connected to the hydraulic control block, rather than PB port connecting directly on to the 3PH line. The 3PH line appears to come directly out of the back of the hydraulic control block. Shouldn't be a big deal for me to confirm this flow and make sure I install the new pressure compensated flow control valve in the right place. Cheers, Paul

chuck172 · Mar 11, 2014

I just bought a new L3200. The 3pt. is jerky. Real jerky. My tractor has 5 hours on it. When the dealer delivered it, I tried the pto and told him it wasn't very smooth. He said that's cause it was cold. Well, that it never did smooth out. Today it was 60* and the lift was the same.
I called Kubota headquarters today and asked if I'm responsible for getting my tractor back to the dealer. They said yes, it's my responsibility. That's a 60 mile round trip. Will cost me $$$.
It doesn't seem fair. Now reading this topic I don't even know if the dealer will be able to fix the problem.
What should I do?

chuck172 · Mar 11, 2014

I just bought a new L3200. The 3pt. is jerky. Real jerky. My tractor has 5 hours on it. When the dealer delivered it, I tried the pto and told him it wasn't very smooth. He said that's cause it was cold. Well, that it never did smooth out. Today it was 60* and the lift was the same.
I called Kubota headquarters today and asked if I'm responsible for getting my tractor back to the dealer. They said yes, it's my responsibility. That's a 60 mile round trip. Will cost me $$$.
It doesn't seem fair. Now reading this topic I don't even know if the dealer will be able to fix the problem.
What should I do?

k0ua · Mar 11, 2014

chuck172 said:
I just bought a new L3200. The 3pt. is jerky. Real jerky. My tractor has 5 hours on it. When the dealer delivered it, I tried the pto and told him it wasn't very smooth. He said that's cause it was cold. Well, that it never did smooth out. Today it was 60* and the lift was the same.
I called Kubota headquarters today and asked if I'm responsible for getting my tractor back to the dealer. They said yes, it's my responsibility. That's a 60 mile round trip. Will cost me $$$.
It doesn't seem fair. Now reading this topic I don't even know if the dealer will be able to fix the problem.
What should I do?

Oh, dear..What can I say, the dozens of threads about this problem... Well here is the deal, some members have said they got the dealers to "fix" them.. although some of the best mechanics on this forum were unable to do so..There is some thought that the dealers replaced the 3pt valve assembly with one for an older Grand L machine at their expense.. I was unable to get Kubota regional to do anything about mine. A few months later After I stated how I was treated on a tractor survey, I received a call from Kubota Corporate. By then I was a Kioti Owner. They said, well I guess we cannot help you. That is all I know to tell you Chuck. I can tell you Kubota Grand L's don't have this problem.. neither do, well you get the picture.

Chilly807 · Mar 11, 2014

If it's bad enough that you're not happy with it, I'd suggest you put pressure on the dealer to take it back on a permanent basis.. since it didn't get better when the tractor warmed up, essentially he misled you. If that works for you, whether you buy another Kubota product is up to you. I don't think they CAN fix it entirely, but that's my opinion only.

Sean

s219 · Mar 11, 2014

I don't believe there is a true fix -- any fixes I have read about have undesirable side effects. Kubota should be responsible, so I'd say give the dealer a call and have them come pick it up. Did you pay cash or finance? If the latter, you have some leverage.

Now, if you experiment, you will find that the jerkiness only happens when you move the lever up in small increments. It should be smooth moving up with large lever increments, and super smooth going down regardless of how you move the lever. The reason large up increments are smooth is that your lever motion is faster than the hitch moves up, so the internal cutoff valve is tapering off flow, and it's smooth. So in reality, if you can lift the lever up faster than the 3-pt hitch moves, then it will be smooth and you won't see the problem.

The way I use implements, I hardly ever run into the problem -- I'm usually always going up in large movements of the lever, so it's smooth. I rarely even think about the problem anymore. But I still think Kubota should be ashamed to ship a product with a defect like this. If it bothers you or interferes with the way you use the tractor, by all means make a stink about it.

kubotacres · Mar 11, 2014

chuck172 said:
I just bought a new L3200. The 3pt. is jerky. Real jerky. My tractor has 5 hours on it. When the dealer delivered it, I tried the pto and told him it wasn't very smooth. He said that's cause it was cold. Well, that it never did smooth out. Today it was 60* and the lift was the same.
I called Kubota headquarters today and asked if I'm responsible for getting my tractor back to the dealer. They said yes, it's my responsibility. That's a 60 mile round trip. Will cost me $$$.
It doesn't seem fair. Now reading this topic I don't even know if the dealer will be able to fix the problem.
What should I do?

Before i start, this is entirely my experience, so I can't speak for everybody. I bought a L3200 and about 2 weeks after operating i noticed the jerky hitch. The only reason i noticed was from using my dad's Grand L up until i bought mine. I researched here on TBN and found out all about the highly popular "jerky hitch". I then called up my dealer about the issue and he told me to bring it down and they would take a look at it. After talking to the sales manager he explained alot to me regarding the issue and set alot of truth straight from I've read on here and other websites. Alot of info i gathered online was true and alot wasn't as I would learn. I left the tractor and 3 days later i received the call to pick it up. Boy was i surprised. Not a single quirk in the hitch. I tried everything from high rpms's small increments on the adjusting,ect. Perfect! I asked what had been done , his reply back was "some small adjustments to the valve assemly". I asked if it would affect the weight capacity of the lift and he replied "no". After returning home and some 2 years later everything he said was true. So when i decided to upgrade and buy a FEL i came back online and discovered the issue at hand of the fel and jerky hitch. It seemed at that time those who could fix the jerky hitch had problems with the FEL. So yet again after talking to the salesmanger, he told me to bring the tractor and don't worry about nothing. He even told me that if i had a issue he would take off the fel and not charge anything for the install. So with that said i had the FEL installed and much to my surprise not a single issue. He also told me that ever since my inital incident that every tractor on his lot gets the valve adjustment before leaving,and i was told that comes straight from Kubota. However i don't understand why Kubota can't fix the dang issue at the factory rather than leaving it up to the dealers...Which is where i think the second inital problem comes from, getting somebody willing to fix it and working on it till it's fixed. With that said don't believe everything you are told. My experiences only.