Backhoe Backhoe Thumb

[davisgary2]

I have a L3560HSTC with a BH92 Backhoe. The backhoe has the mechanical thumb. I want to convert it to Hydraulic. Has anyone ever done this? I already have a cylinder that fits in place of the stiff arm. I am thinking some hoses and a single spool DA valve and I would only be into it for a couple hundred dollars.

Any Thoughts. Thanks

 

[Michael In Tennessee]

If I were doing this (and I might in the future) I'd use a electric valve that you would typically use on a loader 3rd function. You can source 12 volts from under one of the rear fenders usually. Then, buttons on the right stick for activation. It would be a bit more expensive, but not much if you are careful in your switch selection. Knobs with switches can be pricy.

 

[davisgary2]

Thanks Mike I do have a third function for Grapple and Snow Plow. That would be a good way to go but I think above my budget.
After some research I found the valve pictured. I believe I could mount that to the side of the tower that holds the controls at the operator station. Disconnect the connection in the upper left of pictures 3 and 4. Run A new hose from the disconnected port on the backhoe valve body to the in port of the new valve. Then connect the original hose from the out of the new valve to flow back to the tractor.

Am I getting in trouble Yet LOL ? Then two new hoses from the working ports to the new cylinder for the thumb. Tractor has 12.8 gpm total only 8.1 gpm after power steering. So a Valve rated for 10 gpm should be ok?

 

[bdhsfz6]

I have a BH92 on my L6060HSTC and used the 3rd function valve to operate the thumb. I used some hydraulic hose I had laying around and ran it back to the hoe. I also had to wire a switch for the valve near the backhoe seat. It didn't cost much since I had most of the fittings. If I had to buy them now, I'm sure the cost would be over $200 for the project.

You may already know this but do NOT use a rear remote to operate the thumb cylinder. According to the manual, using a rear remote with the BH92 attached can cause damage to the hydraulic system.

BTW, what cylinder did you use to replace the manual strut on the BH92? The one I have works but it isn't the right size.

 

[davisgary2]

Thanks for the idea. No worries as I don't have rear remotes. I have an extra curl cylinder for the loader ( long story ) that appears to be the right length may have to have some minor resizing of the pin holes so they will fit.

 

[nyone]

I would just get another valve section and longer bolts.

 

[rScotty]

with a thumb, you have to have a special relief circuit because the bucket can and will overpower the thumb and pressurize the system. Be sure to do this or you risk your entire hydraulic system.
Just be sure to put in a dedicated relief valve properly plumbed for the thumb.

 

[Michael In Tennessee]

I would just get another valve section and longer bolts.

If you can figure out what valve it is,sure. Sourcing the valve from kubota is expensive.