LX2610 Hydraulic question

[LakeBeagle]

Short version:

Anyone know where there is a return to "tank" (reservoir) connection on this tractor?

Long version:

I recently replaced an old grey market Japanese tractor with a shiny new LX2610HSD. I ordered it with a 3rd function and a single rear remote. Part of the reason for the rear remote was to hook up a little 3 point backhoe I made years ago. It was designed to connect in the power beyond loop on my old tractor. It also has its own relief valve so it needs a return to "tank" connection as well. I have some industrial hydraulic experience from my early engineering days and the principles of hydraulics are not that complex. Unfortunately, the dealer and I didn't speak the same hydraulic vernacular. They did get the backhoe working, well sort of.

Using the rear remote held in the rear most position the backhoe functions. However, the tractor relief valve is constantly relieving whenever the backhoe is not in motion. Not good. It turns out the mechanic who installed the WR Long 3rd function and rear remotes thought the "T" connection on the 3rd function valve was a tank port so that's where he hooked up the return to tank disconnect. In reality it is the power beyond output which I believe goes to the 3 point hitch. I think inserting the backhoe between the 3rd function valve and the 3 point hitch would solve that part of the problem. However, I still need a low pressure return to the reservoir for the backhoe relief valve.

Any suggestions? A hydraulic diagram for the tractor would be great but all my Google searches have failed to locate anything useful.

John

 

[TheOldHokie]

Short version:

Anyone know where there is a return to "tank" (reservoir) connection on this tractor?

Long version:

I recently replaced an old grey market Japanese tractor with a shiny new LX2610HSD. I ordered it with a 3rd function and a single rear remote. Part of the reason for the rear remote was to hook up a little 3 point backhoe I made years ago. It was designed to connect in the power beyond loop on my old tractor. It also has its own relief valve so it needs a return to "tank" connection as well. I have some industrial hydraulic experience from my early engineering days and the principles of hydraulics are not that complex. Unfortunately, the dealer and I didn't speak the same hydraulic vernacular. They did get the backhoe working, well sort of.

Using the rear remote held in the rear most position the backhoe functions. However, the tractor relief valve is constantly relieving whenever the backhoe is not in motion. Not good. It turns out the mechanic who installed the WR Long 3rd function and rear remotes thought the "T" connection on the 3rd function valve was a tank port so that's where he hooked up the return to tank disconnect. In reality it is the power beyond output which I believe goes to the 3 point hitch. I think inserting the backhoe between the 3rd function valve and the 3 point hitch would solve that part of the problem. However, I still need a low pressure return to the reservoir for the backhoe relief valve.

Any suggestions? A hydraulic diagram for the tractor would be great but all my Google searches have failed to locate anything useful.

John

The WR Long valve is plumbed correctly. The T port is used for power beyond.

Does your backhoe valve have both power beyond and tank ports. It's not a silly question because Kubota hoes have a pressure relief but do not have power beyond and Kubota techs are going to be perfectly happy hooking tank port on hoe to power beyond for 3pt.

Dan

 

[TheOldHokie]

Short version:

Anyone know where there is a return to "tank" (reservoir) connection on this tractor?

Long version:

I recently replaced an old grey market Japanese tractor with a shiny new LX2610HSD. I ordered it with a 3rd function and a single rear remote. Part of the reason for the rear remote was to hook up a little 3 point backhoe I made years ago. It was designed to connect in the power beyond loop on my old tractor. It also has its own relief valve so it needs a return to "tank" connection as well. I have some industrial hydraulic experience from my early engineering days and the principles of hydraulics are not that complex. Unfortunately, the dealer and I didn't speak the same hydraulic vernacular. They did get the backhoe working, well sort of.

Using the rear remote held in the rear most position the backhoe functions. However, the tractor relief valve is constantly relieving whenever the backhoe is not in motion. Not good. It turns out the mechanic who installed the WR Long 3rd function and rear remotes thought the "T" connection on the 3rd function valve was a tank port so that's where he hooked up the return to tank disconnect. In reality it is the power beyond output which I believe goes to the 3 point hitch. I think inserting the backhoe between the 3rd function valve and the 3 point hitch would solve that part of the problem. However, I still need a low pressure return to the reservoir for the backhoe relief valve.

Any suggestions? A hydraulic diagram for the tractor would be great but all my Google searches have failed to locate anything useful.

John

OK -I went back and reread your post and I am totally confused. Here is how I think your tractor should have been plumbed without the backhoe.

To add the backhoe you disconnect the T port on the thisrd function at the 3pt and use that hose to feed the backhoe. If you have a PB port on the backhoe it is used to feed the 3pt. If no PB then the T port is used to feed the 3pt. If using the T port the the 3pt lever must be locked in the full down position whenever the hoe is connected. Thats the 100% Kubota blessed design.

Now where is your single remote in this picture? It would NOT BE NEEDED for the backhoe.

Dan

 

[beckmurph]

On my LX2610 with backhoe, the return to tank is under the seat frame.

You can reach it from back end of the tractor.

 

[LakeBeagle]

OK -I went back and reread your post and I am totally confused. Here is how I think your tractor should have been plumbed without the backhoe.

View attachment 112052

To add the backhoe you disconnect the T port on the thisrd function at the 3pt and use that hose to feed the backhoe. If you have a PB port on the backhoe it is used to feed the 3pt. If no PB then the T port is used to feed the 3pt. If using the T port the the 3pt lever must be locked in the full down position whenever the hoe is connected. Thats the 100% Kubota blessed design.

Now where is your single remote in this picture? It would NOT BE NEEDED for the backhoe.

Dan

 

[LakeBeagle]

Dan,

Thanks for the picture it will help describe my challenge. The dealer inserted the WR Long 3rd function exactly as you show in red. Essentially they replaced pipe 90 with the 3rd function valve. So far so good. Then to provide a return to "tank" they ran a separate hose from the "T" port on the 3rd function valve to a disconnect at the back of the tractor. My guess is that the banjo connector, 130 in your diagram, feeds hydraulic power to the 3pt hitch. Somewhere inside the transmission housing the 3pt hitch returns unused hydraulic pressure to the reservoir. If this is true creating a power beyond loop for my backhoe is not the problem. I can break the loop from the "T" port on the 3rd function to the port at 130 with 2 hoses with male/female disconnects. Without the backhoe these hoses would be connected to each other essentially matching the original installation. With the backhoe the hose from the 3rd function "T" port would feed the backhoe and the power beyond port on the backhoe would connect to the other hose completing the loop. But I still need a low pressure return to tank from the relief valve on the backhoe. Which brings me back to my original question. Hopefully, the picture and further description makes my issue more clear.

 

[TheOldHokie]

Dan,

Thanks for the picture it will help describe my challenge. The dealer inserted the WR Long 3rd function exactly as you show in red. Essentially they replaced pipe 90 with the 3rd function valve. So far so good. Then to provide a return to "tank" they ran a separate hose from the "T" port on the 3rd function valve to a disconnect at the back of the tractor. My guess is that the banjo connector, 130 in your diagram, feeds hydraulic power to the 3pt hitch. Somewhere inside the transmission housing the 3pt hitch returns unused hydraulic pressure to the reservoir. If this is true creating a power beyond loop for my backhoe is not the problem. I can break the loop from the "T" port on the 3rd function to the port at 130 with 2 hoses with male/female disconnects. Without the backhoe these hoses would be connected to each other essentially matching the original installation. With the backhoe the hose from the 3rd function "T" port would feed the backhoe and the power beyond port on the backhoe would connect to the other hose completing the loop. But I still need a low pressure return to tank from the relief valve on the backhoe. Which brings me back to my original question. Hopefully, the picture and further description makes my issue more clear.

That's exactly how Kubota does it except that with rare exception their hoes do not have PB so the 3pt valve provides teh tank return. Thats why it must be locked down when the hoe is hooked up.

Since you are not cheating and doing it according to hydraulic Hoyle you can use the loader valve for your tank return. The loader valve has a formed low pressure tank return hose that goes into the side of the transmission. You can cut that hose in two and install a hose barb tee for your additional tank return.

That leaves you with a left over remote valve You can just put it in betweem the 3rd function and outlet for the hoe if you want to keep it.

And just FYI there is another outlet block under the seat. It is immediately upstream of the 3pt valve and has a pressure out and pressure return port. There is a blanking plate on it from the factory
If you want to use it you need to purchase/fabricate a new plate with external ports.

Dan

 

[TheOldHokie]

Here is the diagram for the auxiliary outlet block and factory remotes. You can hijack it for anything you want by fabricating a simple aluminum adapter block with OUT and IN ports in it. It simply bolts on same as the valve adapter I circled in red.

Dan

 

[TheOldHokie]

Dan,

Thanks for the picture it will help describe my challenge. The dealer inserted the WR Long 3rd function exactly as you show in red. Essentially they replaced pipe 90 with the 3rd function valve. So far so good. Then to provide a return to "tank" they ran a separate hose from the "T" port on the 3rd function valve to a disconnect at the back of the tractor. My guess is that the banjo connector, 130 in your diagram, feeds hydraulic power to the 3pt hitch. Somewhere inside the transmission housing the 3pt hitch returns unused hydraulic pressure to the reservoir. If this is true creating a power beyond loop for my backhoe is not the problem. I can break the loop from the "T" port on the 3rd function to the port at 130 with 2 hoses with male/female disconnects. Without the backhoe these hoses would be connected to each other essentially matching the original installation. With the backhoe the hose from the 3rd function "T" port would feed the backhoe and the power beyond port on the backhoe would connect to the other hose completing the loop. But I still need a low pressure return to tank from the relief valve on the backhoe. Which brings me back to my original question. Hopefully, the picture and further description makes my issue more clear.

BTW - as you have learned most (not all) Kubota techs are hydraulic circuit challenged. They blindly install factory equipment according to the instruction sheets Kubota provides and from time to time even manage to screw that up. So your problem was not so much nomenclature as it was a lack of basic understanding on the part of the techs.

Dan

 

[LakeBeagle]

BTW - as you have learned most (not all) Kubota techs are hydraulic circuit challenged. They blindly install factory equipment according to the instruction sheets Kubota provides and from time to time even manage to screw that up. So your problem was not so much nomenclature as it was a lack of basic understanding on the part of the techs.

Dan

Thank you very much. The pictures are a great help and hopefully will allow me to communicate to the dealer more effectively. I will crawl under the tractor tomorrow and confirm it matches the pictures. A younger me would make the necessary changes but those days have passed. The dealer will get the opportunity to make the changes assuming I can get them to understand. I have discovered they have a limited understanding of the fundamentals of hydraulics. I'm no expert but a couple engineering degrees and 36 years of industrial experience help figure out most problems given basic information. Your pictures provide the missing information.

BTW I have the OEM remote shown in your last picture. While it does not really help with the backhoe it will enable a hydraulic top link so it was worthwhile.

 

[TheOldHokie]

Thank you very much. The pictures are a great help and hopefully will allow me to communicate to the dealer more effectively. I will crawl under the tractor tomorrow and confirm it matches the pictures. A younger me would make the necessary changes but those days have passed. The dealer will get the opportunity to make the 7 assuming I can get them to understand. I have discovered they have a limited understanding of the fundamentals of hydraulics. I'm no expert but a couple engineering degrees and 36 years of industrial experience help figure out most problems given basic information. Your pictures provide the missing information.

BTW I have the OEM remote shown in your last picture. While it does not really help with the backhoe it will enable a hydraulic top link so it was worthwhile.

Should be a piece of cake. Tell them to plumb it like a BH77 but use PB not T for the return line. They do those all the time. Then the additional tank return should be easy to explain. I see you are in VA - care to share what dealership is doing the,work?

The factory remotes are super handy.

Dan

 

[LakeBeagle]

Thanks for the BH77 tip and the pictures worth a thousand words...

I bought the tractor from Spaulding Equipment Co. in Randolph, VA (South Boston). They have been good to work with just not real knowledgeable about hydraulics. Only about 30 miles from our house.

 

[TheOldHokie]

Thanks for the BH77 tip and the pictures worth a thousand words...

I bought the tractor from Spaulding Equipment Co. in Randolph, VA (South Boston). They have been good to work with just not real knowledgeable about hydraulics. Only about 30 miles from our house.

Small world - my wife grew up in South Hill (LaCrosse).

Dan