Backhoe Anyone with a Grand L40 series and a backhoe

[Timan]

Can someone please tell me where the hydraulic connection for the backhoe is on a 40 series cab tractor that already has remotes installed using the tap on the top of the hydraulic manifold (under the seat)?
My old 30 series had a seperate block that distributed hydraulic pressure to the backhoe. I cant find any part numbers for this type of block for the 40 series.
Any Help??
Thanks

 

[hayden]

On mine (5740 HSTC), there is a line that runs from the loader valve to the top of the trans case. That's been re-routed to a set of couplers that are either connected to each other when the BH is removed, or connected to the BH mating couplers when installed. I'd have to look at it again to provide more details, so let me know if you need to know more.

I've got the parts (I think) to install a manual diverter value so the fluid flow can be diverted to the BH or bypassed on demand, and more importantly, while the tractor is running. As soon as spring arrives I'll install it all.

 

[Timan]

Thank You for the info Hayden. Are you using a Woods backhoe? Did the connection kit come with the backhoe or is it a Kubota kit?

 

[hayden]

Mine's a Bradco. I'm not sure what came with the BH and what hoses and fittings my dealer supplied themselves. The hydraulic fittings are all standard sizes, though there are several different standards so you need to be sure which one you are working with on each fitting.

Are you planning to install this yourself?

 

[Timan]

Yes, I will install it myself. I just finished installing 2 remotes, top and tilt and draft control.
Im really surprised that Kubota doesn't make a kit to add the remote hydraulic power needed for the backhoe when remotes are already installed. It seems as though they make kits for everything else.
I had a L4330 before this tractor and I believe the power for the backhoe was tied into the Power Beyond circuit which is the circuit you are speaking of that goes from the loader valve to the hydraulic block on top of the transmission only it had a small hydraulic block that kind of manifolded everything together.
I spoke with a rep at Kubota today and he said to tap the main power from the pump and not the power beyong circuit so now I'm really confused.
I appreciate your help on this

 

[hayden]

I think there are a number of places where you could successfully tap the hydraulics, but be carefuly about the various relief valves to be sure there is always at least one in action. From what I can tell, the only relief valve in the standard L40 is in the loader valve, hence it's the first thing in the curcuit. The only exception is when the front 3rd function is installed, and that has a built in relief valve of it's own. My recollection is that it inserts between the pump and loader valve. In the 5740, both are set to about 2900 PSI. My backhoe has a relief valve set to 2500 PSI. Placing it ahead of the loader would reduce the loader, remotes, 3rd function, and lift pressure to 2500 PSI which is a 20% reduction in capacity. With the BH plumbed in just before the transmission case, the only thing that get the reduced 2500PSI is the 3PH, and that's not used when the BH is attached anyway. The loader, 3rd function and remotes all still get 2900 PSI.