BX23S Hydraulic thumb on backhoe

[Gary Francis]

Hi All,

New BX23s owner here. I'm wondering, has anyone tried to fab up a hydraulic cylinder for the mechanical thumb on their BX23s? I'm guessing that you could leverage the 3rd function on the FEL. Just wondering how the electric switching would work or be wired to the loader switch. Any advice is welcomed.

Thanks in advance.
G

 

[Kubit]

Gary,

I run the thumb cylinder by simply reaching the control stick to my left & a bit behind while in the backhoe seat. I have it connected so that the bucket & the thumb controls are moved in the same functional direction so there is no confusion. That is both in "out" position to open & both in "in" position to close--picture your arms in front of you opening & closing. Works pretty smooth, strong grip & of course, no getting off & on tractor.

The cylinder I used was Surplus Center 9-8771-12

Photos:
#1 Connections @ 3F Valve
#2 Connections @ Loader to Tractor Rear
#3 Connections @ Tractor Rear to Backhoe
#4 *Connection @ Top of Cylinder. Note Cross Tube Cut & Welded Parallel to Hydro Fittings. All cylinders that I found had the cross tube perpendicular to the hydro fittings & that would have put the hydro lines in an un-neat route & had them stretched when dipperstick was moved--it could be made to work but I preferrred the route I took.
#5 *Connection @ Bottom of Cylinder
*Note Spacers Required to “center” Cylinder in Thumb

Hope this helps

PS: Forgot (it's been a year). Pic #4: At top of cylinder I added 3/4" THK x 3/4" H x 2 3/4" L spacer. This to increase OAL of cylinder to maximum travel both ways so to accommodate mechanical travel limitations of thumb min/max.

 

[Gary Francis]

Gary,

I run the thumb cylinder by simply reaching the control stick to my left & a bit behind while in the backhoe seat. I have it connected so that the bucket & the thumb controls are moved in the same functional direction so there is no confusion. That is both in "out" position to open & both in "in" position to close--picture your arms in front of you opening & closing. Works pretty smooth, strong grip & of course, no getting off & on tractor.

The cylinder I used was Surplus Center 9-8771-12

Photos:
#1 Connections @ 3F Valve
#2 Connections @ Loader to Tractor Rear
#3 Connections @ Tractor Rear to Backhoe
#4 *Connection @ Top of Cylinder. Note Cross Tube Cut & Welded Parallel to Hydro Fittings. All cylinders that I found had the cross tube perpendicular to the hydro fittings & that would have put the hydro lines in an un-neat route & had them stretched when dipperstick was moved--it could be made to work but I preferrred the route I took.
#5 *Connection @ Bottom of Cylinder
*Note Spacers Required to “center” Cylinder in Thumb

Hope this helps

PS: Forgot (it's been a year). Pic #4: At top of cylinder I added 3/4" THK x 3/4" H x 2 3/4" L spacer. This to increase OAL of cylinder to maximum travel both ways so to accommodate mechanical travel limitations of thumb min/max.

Thanks for the info and sharing the pics. Much appreciated. Now just need to source the cylinder and order a 3rd function kit.

 

[GreensvilleJay]

you can get 2 remotes for the rear (levers fill that 'hole' in the right side behind loader lever)....
one could be the rear thumb, other for a grapple (true,live 3rd function).

 

[GaltsGulch]

Paul & Kathy Short have a few vids on YouTube where he added it, pretty much the same as Kubit did. Used his third function from his loader to run it. That was how I was planning on doing it if I ever get my BXPanded thumb. Been watching for the delivery email for a couple weeks now. It will be along soon I hope.

 

[BXHoosier]

When I built the thumb for my BX24, I found a 2”x8” log lift cylinder that has the ports on the correct side so that I didn’t have to modify it. I added dual rear hydraulic remotes with a valve from a JD garden tractor that I use to control the thumb.

 

[Xizervexius]

I've been trying to place rocks for a rock wall with my bx23s using the manual thumb while inventing new curse words. A hydraulic thumb would make this task, and others, so much simpler.
I found one video where they installed a Kubota factory hyd thumb kit, part number BT1975, but its for a BX25.
Not really sure what the differences are, would this work for a BX23S?

 

[hoening]

I’m trying to do the same thing on my Bx23s tlb as well as add rear remote using the kubota kit which supposedly will not work on bh models? To add the hydraulic thumb I’m trying to determine if the scv’s on the bh can modified to extend the power beyond to a new valve for the hydraulic thumb and then back to tank. Don’t know who makes kubota’s valves and right now the tractor is at my cabin so haven’t looked at them yet to see if this can be done. I think I’ll be able get the rear remote kit to work if I incorporate some tee’s in the lines to be able to maintain the bh connections.
Not an answer to your question but I’ve learned a lot researching what I want to do and thought I would share.

 

[TheOldHokie]

I’m trying to do the same thing on my Bx23s tlb as well as add rear remote using the kubota kit which supposedly will not work on bh models? To add the hydraulic thumb I’m trying to determine if the scv’s on the bh can modified to extend the power beyond to a new valve for the hydraulic thumb and then back to tank. Don’t know who makes kubota’s valves and right now the tractor is at my cabin so haven’t looked at them yet to see if this can be done. I think I’ll be able get the rear remote kit to work if I incorporate some tee’s in the lines to be able to maintain the bh connections.
Not an answer to your question but I’ve learned a lot researching what I want to do and thought I would share.

The add-on valve for the thumb is the least of your worries. You can easily put it ahead of or after the backhoe valve. If you put it ahead of the hoe it will likely block all hoe functions when the thumb is being acutated. If you put it after the hoe the hoe may or may not block the thumb depending on the design of the Kubota valve. I would have to look at the WSM to see how it works to answer that question.

In either case pick a location on the hoe for mounting the add-on valve. Next you have three hoses going to the tractor from the hoe - ports A, B and C as shown in the attached drawing. All of the plumbing is done on the backhoe itself using those ports and three new hoses.

1. To put the valve ahead of the hoe disconnect the pressure IN hose from the backhoe valve (port A) and connect it to the pressure IN on your new valve. Then using a new hose connect the power beyond port on your new valve to pressure IN (port A) on the backhoe valve.
2. To put the valve after the hoe disconnect the power beyond hose from the backhoe valve (port C) and connect it to the power beyond port on the new valve. Then using another new hose connect the power beyond port (port C) on the backhoe valve to pressure IN on the new valve
3. Lastly put a tee on the tank return port (B) of the backhoe valve and connect the existing tank return hose going to the tractor to the tee. Then using the third new hose connct the tank return port on your new valve to the third leg of the tee.

All done except plumbing the lines to the thumb cylinder.

Now the Kubota OEM remote kit is another issue. What kit is that and how are you planning on using it?

Dan

 

[DustyRusty]

It might be easier to use the LandPride 3rd function kit that is made for the BX23S, and also purchase a second 3rd function knob from LandPride to use on the backhoe. Then splice the second 3rd function knob that is mounted on the backhoe into the wiring for the 3rd function loader valve knob. You will need to add a male and female electrical connector to the wiring so you can still remove the backhoe from the tractor. I would plumb the thumb cylinder with short hoses and use flat-faced male and female couplers on those hoses. Then have 2 lines that will go from the 3rd function valve that is mounted on the left side of the tractor and run them back to the backhoe and plug them into the 2 short hoses on the thumb. You need the dealer training PDF to fully understand how the LandPride 3rd function mounts to the BX23S. What I described might sound difficult to accomplish, but it is quite easy and straightforward.
I just looked up the LandPride 3rd function valve price and got sticker shock. I paid $830 (07/2602021), and today it is $1087.30! The control knob went from $180.19 to 236.29! I guess that you should forget my suggestion.

 

[TheOldHokie]

It might be easier to use the LandPride 3rd function kit that is made for the BX23S, and also purchase a second 3rd function knob from LandPride to use on the backhoe. Then splice the second 3rd function knob that is mounted on the backhoe into the wiring for the 3rd function loader valve knob. You will need to add a male and female electrical connector to the wiring so you can still remove the backhoe from the tractor. I would plumb the thumb cylinder with short hoses and use flat-faced male and female couplers on those hoses. Then have 2 lines that will go from the 3rd function valve that is mounted on the left side of the tractor and run them back to the backhoe and plug them into the 2 short hoses on the thumb. You need the dealer training PDF to fully understand how the LandPride 3rd function mounts to the BX23S. What I described might sound difficult to accomplish, but it is quite easy and straightforward.
I just looked up the LandPride 3rd function valve price and got sticker shock. I paid $830 (07/2602021), and today it is $1087.30! The control knob went from $180.19 to 236.29! I guess that you should forget my suggestion.

KISS. You can put a simple D03 solenoid valve (seventh function ???) on the backhoe itself for around $150. It plumbs in exactly as I described earlier except there is no tank return. It would not take a lot of ingenuuity to mount it directly on the power beyond port of the backhoe valve. A fancy-spansy replacement joystick knob with buttons costs more than the valve and subplate.

Dan

 

[Dave Ogren]

If a person had the rear remote to operate a hydraulic top link, could that be used to operate the thumb??
Dave

 

[GreensvilleJay]

yes, it could.....

 

[TheOldHokie]

If a person had the rear remote to operate a hydraulic top link, could that be used to operate the thumb??
Dave

The thumb don;t care where the valve is but you would have to connect the thumb hoses into the rear remote outlets. Only a minor inconvneience to be dealt with when mounting and dismounting the hoe. Also likely operation of the thumb will block all other backhoe functions. Putting a valve in the power beyond outlet of the back hoe valve gives the backhoe priority.

Dan

 

[hoening]

Just seeing all the replies. Thought I would have gotten email notices when something was posted? Anyway, thank you for the input. I will update in the spring when I take off the snowblower and can work on my tractor. Too cold in the garage UP there right now.

 

[hoening]

Just seeing all the replies. Thought I would have gotten email notices when something was posted? Anyway, thank you for the input. I will update in the spring when I take off the snowblower and can work on my tractor. Too cold in the garage UP there right now.

The backhoe control valve I believe comes from Roquet Group company https://www.roquetgroup.com/en/products1/c/298-202p-|-monoblock-parallel-|-flow-rate-60-lmin.html
They do not show a PB fitting to be able to add another valve for a hydraulic thumb but there does appear the valve has the openings in the monoblock to be able to incorporate one to add this valve. Will try to reach out to them to get more info.

 

[TheOldHokie]

The backhoe control valve I believe comes from Roquet Group company https://www.roquetgroup.com/en/products1/c/298-202p-|-monoblock-parallel-|-flow-rate-60-lmin.html
They do not show a PB fitting to be able to add another valve for a hydraulic thumb but there does appear the valve has the openings in the monoblock to be able to incorporate one to add this valve. Will try to reach out to them to get more info.

Your BT603 backhoe has three hoses - one is pump pressure from the tractor, one is power beyond out back to the tractor , and the third is tank return to the tractor. You can add a valve for a thumb at either pump supply or power beyond out. If you use one of the ubiquitous D03 3rd function solenoid valves you can put it on the pump side (ahead) of the backhoe valve and it will work in series with all other backhoe functions. If you put it after the backhoe valve (power beyond) the backhoe functions will block the thumb and you will only be able to use it when all backhoe spools are in neutral.

Put the switch for the valve on the joystick for the backhoe bucket and it will operate just like a front loader grapple.

Dan

 

[DustyRusty]

I was just wondering if anyone that has done this modification to their backhoe has any updates and pictures to post showing their progress. In old age, I move more slowly and am still contemplating moving forward with this project.

 

[TheOldHokie]

I was just wondering if anyone that has done this modification to their backhoe has any updates and pictures to post showing their progress. In old age, I move more slowly and am still contemplating moving forward with this project.

Which modification - several were discussed?

Dan

 

[DustyRusty]

Actually, I like te modification for the BX25 since it was a off the shelf cylinder without any modifications. Last night I googled the cylinder and found a CYLINDER: 2" BORE, 8" STROKE, 1.25" ROD, 3 O'CLOCK PORTS for under $100. https://ruggedmade.com/log-lift-cylinder-2-bore-8-stroke-3-o-clock-ports.html I am thinking of ordering this cylinder, however, I just need to check the lengths of the thumb open and closed. It would be a lot easier on my old body not to have to get off and on the tractor to move the thumb.