Mechanical thumb to hydraulic on BH 92

[bikerdib]

Hello friends. I have an L4701 with 2 rear remotes and a BH92 that I already have a mechanical thumb on. I'm wondering if I could buy the ram for the hydraulic thumb kit from Kubota parts and simply use one of the rear remotes to operate the thumb? I would get the entire kit but man oh man... $$$$

I know I wouldn't be able to operate both the thumb and the backhoe bucket at the same time but for my use it wouldn't ever be necessary. I just want to be able to set the thumb position then use the backhoe without having to climb off and on the backhoe to set the mechanical thumb position.

 

[GreensvilleJay]

I don't know your tractor but...
..If you have two remotes, why can't you use BH and thumb at the same time ?
Remotes are totally separate from the BH

 

[Donystoy]

Hello friends. I have an L4701 with 2 rear remotes and a BH92 that I already have a mechanical thumb on. I'm wondering if I could buy the ram for the hydraulic thumb kit from Kubota parts and simply use one of the rear remotes to operate the thumb? I would get the entire kit but man oh man... $$$$

I know I wouldn't be able to operate both the thumb and the backhoe bucket at the same time but for my use it wouldn't ever be necessary. I just want to be able to set the thumb position then use the backhoe without having to climb off and on the backhoe to set the mechanical thumb position.

I also have a mechanical thumb that I hope to someday add hydraulics to. My plan is to just install a generic control valve of proper capacity and install it in series with the pressure hose supplying the BH. My hydraulics comes from a pto driven pump where I believe yours comes from one of the remotes on the tractor. I see no reason as to why you could not do the same assuming yours is an open center system like most are. You could probably even fab up a foot pedal mechanism which would give you the same function as the oem for the BH92. Just depends on how good you are with fabrication. My mechanical thumb I fabricated when I had to remove the dipper to weld up a crack that had appeared. I designed it to accept an economical generic hydraulic cylinder available to me.

 

[BXHoosier]

I use my rear remotes to run the homemade thumb on my BX24. I used a 2”x8” log lift cylinder because it has the ports on the side where they’re less likely to get damaged.

 

[bikerdib]

Yes, I'm pretty sure I can make everything work as far as setup and plumbing the thumb, my main concern and question at this point is if there is a possibility of damaging the remote hydro circuit? The curl on the BH bucket has a lot of force so could it damage the rear remote valve or worse?

 

[Tarmy]

Go for it OP...it is the handiest tool I own. No more jumping on and off the BH. I swapped mine over and plumbed it myself. Bought aftermarket ram.

 

[ruger1980]

The problem with running a hyd. thumb off a rear remote or separate control valve is there is no circuit relief. In this situation you can easily over power the thumb and bend stuff. I have seen this happen before even with a circuit relief installed but set too high.

 

[kubotafreak]

Hello friends. I have an L4701 with 2 rear remotes and a BH92 that I already have a mechanical thumb on. I'm wondering if I could buy the ram for the hydraulic thumb kit from Kubota parts and simply use one of the rear remotes to operate the thumb? I would get the entire kit but man oh man... $$$$

I know I wouldn't be able to operate both the thumb and the backhoe bucket at the same time but for my use it wouldn't ever be necessary. I just want to be able to set the thumb position then use the backhoe without having to climb off and on the backhoe to set the mechanical thumb position.

I did just that. I bought the factory valve kit (pedal) from dealer. Then waited and found a used cylinder for the thumb on ebay for 200$. Factory and works great. Has its own adjustable relief as mentioned earlier. Take it one step further like my sig and get the quick change buckets. The k7770 quick coupler for the l47 fits, and allows the excavator buckets to be used.