L6060 Jumpy at low speeds + stuck in gear intermittent.

[Josh Schneider]

Hello all, thank you for all the great post’s on this forum. I am a Marine Mechanic by trade and come from that side of the mechanical spectrum. A lot of tractor related stuff is a little foreign to me with hydrostat. Etc. I am learning a lot. I thank all the previous posts i have read and have helped me with little issues i have chased.

First off my tractor is a 2015 L6060 HSTC.

I am running across one last issue with my tractor (owned it for about 2 months) and it keeps haunting me. The issues i have is sometimes the tractor will get “stuck” in gear. Sometimes in Reverse and sometimes in forward. If stuck in reverse i have to move the HST pedal to about half throttle in Forward position to obtain “neutral”. Vice versa for Reverse. This issue took a month to show up. Happened twice in a week and now has not happened since for about 2 weeks. (Resolved with letting tractor sit for a few minutes to an hour or more) The other problem is it is very jerky at low throttle input. Mainly reverse but sometimes forward. I am hoping this has something to do with the other issue.

I have read many posts and one in particular from a member peaceofprairie seems to be similar to my issue.

L3540 HST driving strange - Swash Plate Sensor fix

Hi Orange gang, Long time lurker - I've saved so much money with fixes and advice from this forum. I just fixed my hydrostat error, and thought I'd share. Symptom: Hydrostat pedal in Neutral, but tractor is moving as if it's about 1/3 depressed in the forward direction. I had to hold the...

www.orangetractortalks.com

To resolve the issue i am having i have tried to understand the HST electronic system and done lot’s of reading in the WSM. I think i have understood the system and believe the HST pedal sensor speaks to the ECU(computer) and the ECU tells the forward and reverse solenoids/proportional valves what to do. However i have one question, what does the Swash plate sensor play a role in? Could this be causing my issue? My manual states in the section “error message does not indicate on LCD” and sub section “Machine will not stop in Neutral position” page 3-S11, it states that potentiometer damaged.

I replaced the HST pedal sensor a few weeks back and thought this had solved the issue. I did do the “fine adjustment procedure” as well when sensor replaced. The tractor has acted up since.

My question is when i go to page 9-S55 in the manual that the troubleshooting guide takes me to it lists the HST pedal Sensor and Swashplate sensor as potential culprits. It also lists the Hand throttle sensor which i assume would have no effect on this issue.


I wanted to dig a little deeper after reading the link i posted and wanted to do some more electronic testing to see what the swash plate sensor controls? .I have read up on using the Intellipanel and what a handy feature. I had it in mode A and was watching MA readings on FWD solenoid and Reverse. To start my diagnosis on the jumpy issue i placed the range selector in Neutral, i slowly and gradually applied my foot in the forward position from N to wide open, readings were very smooth and steady.

Now the good part. I try this now in Reverse and slowly apply throttle, i stop at about 1/4 throttle and notice my reverse solenoid and FWD solenoid are bouncing on and off constantly (this makes sense why my reverse is so jerky on and off.) so this diagnosis leads me back to what role the swash sensor plays and how it could effect this. I now know the forward and reverse solenoids are activating when pedal is applied in Reverse. What could cause this?? Could this also be causing the stuck in gear issue as well?

Going to make a small quick video and post a link. I feel my well written paragraphs in my head will not communicate to others well and be confusing, if you are still reading thank you for taking the time to read this.

will post up the link shortly to my video. I hope i can compile a nice thread to help others. I have ran across many threads with dead ends and hope i can take this to the finish line and help others in the future.

Josh

 

[Josh Schneider]

Kubota L6060 surges and intermittently stuck in gear

A link to my video showing the “jerky” motion.

 

[mikester]

Do a full hydraulic oil and filters change if this is a new to you machine.

 

[Josh Schneider]

Do a full hydraulic oil and filters change if this is a new to you machine.

Thanks Mikester.

fluids and filters on everything have been changed and swapped out with all Kubota fluids and filters.

 

[Matt Ellerbee]

I’m really no help, but I think you’re on the right track with the swash plate sensor. No idea how it ties in, but after watching your numbers jump around, that’s gotta be it.

Also, damn fine question asking. Lots of info of what has got you to this point.

 

[SDT]

Hello all, thank you for all the great post’s on this forum. I am a Marine Mechanic by trade and come from that side of the mechanical spectrum. A lot of tractor related stuff is a little foreign to me with hydrostat. Etc. I am learning a lot. I thank all the previous posts i have read and have helped me with little issues i have chased.

First off my tractor is a 2015 L6060 HSTC.

I am running across one last issue with my tractor (owned it for about 2 months) and it keeps haunting me. The issues i have is sometimes the tractor will get “stuck” in gear. Sometimes in Reverse and sometimes in forward. If stuck in reverse i have to move the HST pedal to about half throttle in Forward position to obtain “neutral”. Vice versa for Reverse. This issue took a month to show up. Happened twice in a week and now has not happened since for about 2 weeks. (Resolved with letting tractor sit for a few minutes to an hour or more) The other problem is it is very jerky at low throttle input. Mainly reverse but sometimes forward. I am hoping this has something to do with the other issue.

I have read many posts and one in particular from a member peaceofprairie seems to be similar to my issue.

L3540 HST driving strange - Swash Plate Sensor fix

Hi Orange gang, Long time lurker - I've saved so much money with fixes and advice from this forum. I just fixed my hydrostat error, and thought I'd share. Symptom: Hydrostat pedal in Neutral, but tractor is moving as if it's about 1/3 depressed in the forward direction. I had to hold the...

www.orangetractortalks.com

To resolve the issue i am having i have tried to understand the HST electronic system and done lot’s of reading in the WSM. I think i have understood the system and believe the HST pedal sensor speaks to the ECU(computer) and the ECU tells the forward and reverse solenoids/proportional valves what to do. However i have one question, what does the Swash plate sensor play a role in? Could this be causing my issue? My manual states in the section “error message does not indicate on LCD” and sub section “Machine will not stop in Neutral position” page 3-S11, it states that potentiometer damaged.

I replaced the HST pedal sensor a few weeks back and thought this had solved the issue. I did do the “fine adjustment procedure” as well when sensor replaced. The tractor has acted up since.

My question is when i go to page 9-S55 in the manual that the troubleshooting guide takes me to it lists the HST pedal Sensor and Swashplate sensor as potential culprits. It also lists the Hand throttle sensor which i assume would have no effect on this issue.


I wanted to dig a little deeper after reading the link i posted and wanted to do some more electronic testing to see what the swash plate sensor controls? .I have read up on using the Intellipanel and what a handy feature. I had it in mode A and was watching MA readings on FWD solenoid and Reverse. To start my diagnosis on the jumpy issue i placed the range selector in Neutral, i slowly and gradually applied my foot in the forward position from N to wide open, readings were very smooth and steady.

Now the good part. I try this now in Reverse and slowly apply throttle, i stop at about 1/4 throttle and notice my reverse solenoid and FWD solenoid are bouncing on and off constantly (this makes sense why my reverse is so jerky on and off.) so this diagnosis leads me back to what role the swash sensor plays and how it could effect this. I now know the forward and reverse solenoids are activating when pedal is applied in Reverse. What could cause this?? Could this also be causing the stuck in gear issue as well?

Going to make a small quick video and post a link. I feel my well written paragraphs in my head will not communicate to others well and be confusing, if you are still reading thank you for taking the time to read this.

will post up the link shortly to my video. I hope i can compile a nice thread to help others. I have ran across many threads with dead ends and hope i can take this to the finish line and help others in the future.

Josh

Suggest reading about the HST response setting in the Operator's Manual (not WSM). Perhaps setting the response to a less responsive value will help.

Briefly, the swash plate controls the displacement (flow) of the variable displacement pump driven by the engine and ultimately the speed of the tractor.

I suspect that there is nothing wrong with your HST but rather a lack of familiarity with HST operation is likely the issue.

 

[Josh Schneider]

Suggest reading about the HST response setting in the Operator's Manual (not WSM). Perhaps setting the response to a less responsive value will help.

Briefly, the swash plate controls the displacement (flow) of the variable displacement pump driven by the engine and ultimately the speed of the tractor.

I suspect that there is nothing wrong with your HST but rather a lack of familiarity with HST operation is likely the issue.

Thank you very much. I will have to download an owners manual and check it. That is one thing i wish to mess with and haven’t taken the time to read about the response. Thank you.

 

[Josh Schneider]

I’m really no help, but I think you’re on the right track with the swash plate sensor. No idea how it ties in, but after watching your numbers jump around, that’s gotta be it.

Also, damn fine question asking. Lots of info of what has got you to this point.

Thanks Matt. I did not want to be the guy that post’s a “help” and make my life easier. I have been working hard on diagnosing and trying to do it all proper. I was just having trouble understanding what role the Swash Plate sensor plays. The jumpy readings are really funky in my head.

 

[Matt Ellerbee]

Quick google had this.

https://www.kubotabooks.com/AutoIndex/index.php?dir=Tractor%20Owners%20Manuals/&file=L3560%20to%20L6060%20WSM.pdf

Mode

Kubota WSM L3560 Manual Online: Mode ''K'' (Hst Pedal And Range Shift Lever Fine-Adjustment Mode). NOTE • When one of the followings is replaced, this adjustment is required. (Main ECU, HST pedal sensor, swashplate position sensor, range gear shift sensor, HST proportional valve (Forward...

www.manualslib.com

This popped up too. I know you said you went through the fine adjustment, maybe do it again?

Have you gone through to see if you have any codes?

 

[Josh Schneider]

Quick google had this.

https://www.kubotabooks.com/AutoIndex/index.php?dir=Tractor%20Owners%20Manuals/&file=L3560%20to%20L6060%20WSM.pdf

Mode

Kubota WSM L3560 Manual Online: Mode ''K'' (Hst Pedal And Range Shift Lever Fine-Adjustment Mode). NOTE • When one of the followings is replaced, this adjustment is required. (Main ECU, HST pedal sensor, swashplate position sensor, range gear shift sensor, HST proportional valve (Forward...

www.manualslib.com

This popped up too. I know you said you went through the fine adjustment, maybe do it again?

Have you gone through to see if you have any codes?

Thanks Matt. Yes i tried the fine adjustment last night again with no improvement.

no codes are present at all.

when i looked on the WSM it specified for the tractor moves when in neutral and no codes present that the HST Sensor, Swash and throttle. I believe the throttle is on the same page just for a reset. However the weird jumpy MA readings are a concern of mine still.

 

[mikester]

Thanks Mikester.

fluids and filters on everything have been changed and swapped out with all Kubota fluids and filters.

My machine operates much smoother after changing the hydraulic fluids.

I'm not clear on your problem description.

I was having weird hurky jerky and lugging issues. For me the root cause was dirty electrical contacts in the fwd/rev servos. Here's a link to my post describing the issue and resolution:

Kubota L4701 Sometimes Stalls When Moving Forward with HST Pedal

This winter I've been having a problem with the tractor where it starts fine, and then when I press the HST pedal to move forward it stalls. If I leave off the pedal quickly it will not stall and RPMs will come back up. Interestingly, when pressing the pedal for reverse it does not stall. Is...

www.tractorbynet.com

For "stuck in gear" are you clutching when shifting gears?

 

[D2Cat]

Mikester, I like your description of necessary tools to clean the contacts! "... servo harness clips are a SOB to get at unless you have alien long skinny hands and fingers." Good word picture for sure.

 

[Josh Schneider]

My machine operates much smoother after changing the hydraulic fluids.

I'm not clear on your problem description.

I was having weird hurky jerky and lugging issues. For me the root cause was dirty electrical contacts in the fwd/rev servos. Here's a link to my post describing the issue and resolution:

Kubota L4701 Sometimes Stalls When Moving Forward with HST Pedal

This winter I've been having a problem with the tractor where it starts fine, and then when I press the HST pedal to move forward it stalls. If I leave off the pedal quickly it will not stall and RPMs will come back up. Interestingly, when pressing the pedal for reverse it does not stall. Is...

www.tractorbynet.com

For "stuck in gear" are you clutching when shifting gears?

Thanks Mikester,

So basically in video you can see it activating forward and reverse when i am only pressing reverse slightly. I did clean the contacts and checked everything for corrosion/loose ends and all checked out. I thank you for the input on that possible cause.

I replaced my swash plate sensor, turning it while testing with a volt meter resulted in some odd voltage reading jumping around. So i replaced the sensor. However on tractor dash readings OK. I trusted my multimeter more for the jumpy readings.

After installing i checked the readings on tractor and drive ability. It still bucks, surges, pulses, jerky or however one might describe it in Reverse.

I went through the troubleshooting page in the WSM showing all sensor specs and every sensor on the whole troubleshooting page checked out within range and performed well. Including the FWD and REV solenoids. Spec was 0-1600MA and both perfect…..

At last attempt before starting to trace wiring i removed the FWD and REV solenoids and swapped their positions. Upon startup of tractor and while watching and testing on screen the jerky issue that commonly happened in reverse had now moved to the forward position. As i press the pedal FWD the tractor is Jerky, Reverse smooth as silk and problem has reversed itself. Also on the dash on the diagnostic screen where my problem of the fwd and rev solenoids activating when only pressing reverse, you guessed it, they both activate back and forth in FWD now.

Looks like i solved my problem and a new solenoid should be ordered.

Called for parts and my Dad was getting them for me. He spoke to a Kubota tech at the dealer and told him our issue. He said it sounds like a failing solenoid valve. He recommends from his experience change both because the other one usually fails very shortly after the one is replaced. I am excited to finally get to the bottom of this. Will report back and hope to close this thread off with a resolved issue to help others. I ran across many threads with similar symptoms but none ever got to the bottom of it. Will report back when new Solenoids are installed.


As far as the intermittent stuck in gear issue , since it is a HST, i’ll let off the pedal and return it to Neutral. The tractor keeps going in FWD with no way of stopping it. With all my diagnosing i am wondering if a solenoid was sticking and keeping me moving in that direction.

Anyways rambled on enough. Will report back when issue is resolved.

 

[Josh Schneider]

Well Everyone, to finish off this thread and make it handy for someone else having issues i hope to make this paragraph quick and simple.

My Complaint: tractor is very surgey, jerky, pulsing etc on low throttle input. Sometimes fwd’s , sometimes rev. The odd time could be once a month or 3 times a week it would get stuck in gear. By that i mean i let off the pedal to N and tractor goes fwds still or sometimes in reverse.

To solve the jerky feel i finally at wits end swapped the fwd solenoid on HST and Reverse solenoid and the problem moved from REV to FWD. This was very hard to diagnose because both solenoids test within specs. Anyways dealer recommend replace as a pair because the other one would fail not long after. I have replaced both solenoids today and did a mode K fine adjustment reset. Tractor is smooth as silk and solved all issues.

I swapped the swash plate sensor while in there with tank lowered to save a future headache.

I really don’t know what solved the stuck in gear issue because it was so intermittent and so random as sometimes FWD and other times reverse. I want to say maybe a solenoid was sticking and causing it to keep running in one direction. Anyways that was my adventure. If you are reading this and having issues and need a hand don’y hesitate to reach out to me.

thanks to everyone who chimed in.

Josh

 

[retired farmer]

Well Everyone, to finish off this thread and make it handy for someone else having issues i hope to make this paragraph quick and simple.

My Complaint: tractor is very surgey, jerky, pulsing etc on low throttle input. Sometimes fwd’s , sometimes rev. The odd time could be once a month or 3 times a week it would get stuck in gear. By that i mean i let off the pedal to N and tractor goes fwds still or sometimes in reverse.

To solve the jerky feel i finally at wits end swapped the fwd solenoid on HST and Reverse solenoid and the problem moved from REV to FWD. This was very hard to diagnose because both solenoids test within specs. Anyways dealer recommend replace as a pair because the other one would fail not long after. I have replaced both solenoids today and did a mode K fine adjustment reset. Tractor is smooth as silk and solved all issues.

I swapped the swash plate sensor while in there with tank lowered to save a future headache.

I really don’t know what solved the stuck in gear issue because it was so intermittent and so random as sometimes FWD and other times reverse. I want to say maybe a solenoid was sticking and causing it to keep running in one direction. Anyways that was my adventure. If you are reading this and having issues and need a hand don’y hesitate to reach out to me.

thanks to everyone who chimed in.

Josh

You get a attaboy for reporting your happy ending.
rr

 

[Matthew Secours]

Hi Josh, me too am having the same problem with my 2015 L6060 jerking at low speed FWD. i pulled up the forward and reverse Sol display on the tractor and it’s the same speradic readings as you but while driving FWD, i suspect the solenoids, how did you go about changing them ? Do you have a page that refers to changing the solenoids ?
thanks Matthew

 

[Josh Schneider]

Hi Josh, me too am having the same problem with my 2015 L6060 jerking at low speed FWD. i pulled up the forward and reverse Sol display on the tractor and it’s the same speradic readings as you but while driving FWD, i suspect the solenoids, how did you go about changing them ? Do you have a page that refers to changing the solenoids ?
thanks Matthew

Hey Matthew I’m glad that I was able to help someone!

I strongly recommend replace the forward and reverse. The mechanic at the dealer said if one fails the other will sooner than later.

I don’t have a page to help you but will try my best.

go to the right side of the tractor and put a jack under the fuel tank, loosen the bolts at the back support behind the tank and front i believe, the tank will lower down slowly and will give you access to the solenoids. It is tight but can be done. It requires a 5mm allen key i believe to remove them. Make sure the allen is seated as these bolts strip easy. Swap them out and you should be set. Good luck!!

 

[Matthew Secours]

Thanks Josh,

Sure enough it was that front HSt proportional valve, I changed both to be safe and it’s working great now, ready for another snow storm! Expensive little valves haha. Thanks for all the help!

 

[Jmanter]

Can you lower just the right side fuel tank or do you have to follow the full procedure and lower both?




go to the right side of the tractor and put a jack under the fuel tank, loosen the bolts at the back support behind the tank and front i believe, the tank will lower down slowly and will give you access to the solenoids. It is tight but can be done.

 

[Josh Schneider]

Can you lower just the right side fuel tank or do you have to follow the full procedure and lower both?




go to the right side of the tractor and put a jack under the fuel tank, loosen the bolts at the back support behind the tank and front i believe, the tank will lower down slowly and will give you access to the solenoids. It is tight but can be done.

I just lowered the one side and had enough room yes.