Hydraulic Question

[CSalemi]

I’m getting a third function valve installed on my L3901 to allow me to get a grapple.
But it made me think about my BH77 backhoe.
There is only one line going to the backhoe, but I have two controls for the backhoe.
Does the backhoe have some sharing/diverter system built-in?
If so, why can’t the loader do the same?

 

[mikester]

The answer is "it depends" on your plumbing and your hydraulics.

 

[torch]

I’m getting a third function valve installed on my L3901 to allow me to get a grapple.
But it made me think about my BH77 backhoe.
There is only one line going to the backhoe, but I have two controls for the backhoe.
Does the backhoe have some sharing/diverter system built-in?
If so, why can’t the loader do the same?

It's built into the control valve set. The backhoe controls have internal passages to route the flow in the bank of spool valves according to the position(s) of the lever(s). As with the loader control.

However, you are adding an external control with it's own independent spool valve. There is no way to interface that spool valve directly with the bank in the existing FEL control. The additional control must be fed via the "Power Beyond" outlet on the FEL bank.

Now, it is certainly possible to design a FEL control bank with an additional spool valve for a grapple. And perhaps one is available via the aftermarket. But it costs more to add spools and Kubota has apparently opted to keep the base FEL price down. You pay more as a grapple consumer because you have to buy the kit if you add a grapple which is certainly more than the cost of adding another control to the existing bank at the factory. But those without a grapple pay a little less for the FEL alone.

 

[Fedup]

The loader "can do the same". You can put as many valves as you want in series if use the power beyond concept. Many people have done it many times. You don't need electric valves.

 

[Russell King]

To add a bit more to this, you can also stack valves together and they then share the hydraulic fluid from the pump so no extra hoses required. Those usually each have a lever that operates one valve at a time. But for some they arrange linkages so one handle can control all the valves (like the FEL)

 

[TheOldHokie]

I’m getting a third function valve installed on my L3901 to allow me to get a grapple.
But it made me think about my BH77 backhoe.
There is only one line going to the backhoe, but I have two controls for the backhoe.
Does the backhoe have some sharing/diverter system built-in?
If so, why can’t the loader do the same?

The backhoe has two lines, one in and one out.

The third function will also have two hoses, one in amd one out.

Dan

 

[TheOldHokie]

Now, it is certainly possible to design a FEL control bank with an additional spool valve for a grapple. And perhaps one is available via the aftermarket. But it costs more to add spools and Kubota has apparently opted to keep the base FEL price down. You pay more as a grapple consumer because you have to buy the kit if you add a grapple which is certainly more than the cost of adding another control to the existing bank at the factory. But those without a grapple pay a little less for the FEL alone.

Kubota is not keeping valve prices down. Just the opposite. This 3 spool loader valve sells for 1/5th the cost of a 2 spool Kubota valve.

Dan

 

[CSalemi]

It's built into the control valve set. The backhoe controls have internal passages to route the flow in the bank of spool valves according to the position(s) of the lever(s). As with the loader control.

However, you are adding an external control with it's own independent spool valve. There is no way to interface that spool valve directly with the bank in the existing FEL control. The additional control must be fed via the "Power Beyond" outlet on the FEL bank.

Now, it is certainly possible to design a FEL control bank with an additional spool valve for a grapple. And perhaps one is available via the aftermarket. But it costs more to add spools and Kubota has apparently opted to keep the base FEL price down. You pay more as a grapple consumer because you have to buy the kit if you add a grapple which is certainly more than the cost of adding another control to the existing bank at the factory. But those without a grapple pay a little less for the FEL alone.

Thanks for the good explanation