Woods BH70-X to Kubota B3200 hydraulics connections.

[JCC]

I have a BH70-X backhoe which I want to mount to a Kubota B3200 tractor. On the B3200 the loader power beyond port goes to the 3PH. To mount the BH70-X I need to re-route the PB port to the BH but then I need a PB port on the BH to go to the 3PH.

Anyone know how to configure the BH70-X to have PB port? The manual has a drawing with a plug that goes on the BH output port to route the oil to the BH power beyond port but it looks like that simply re-routes the BH output tank port to the PB port, there would not be any oil coming out of the output port anymore?

That seems not right to me, would not the BH valve be exposed to high pressure when the 3PH is operated? Just as would happen if the BH output port was connected to the 3PH instead of the tank. That kind of makes the BH PB port irrelevant. If the BH output port is plugged no oil would come out of it so it could be just left free?

Is that the proper configuration, that is plug the BH output, route the BH PB to the 3PH and leave the output port free?

I appreciate any feedback on this as I am a hydraulics noob.

 

[oldnslo]

connections required like you state power beyond from loader to inlet of the backhoe.

Power beyond of the backhoe to 3PH

Tank of the back hoe directly to tank on the tractor. This can be teed into the loader tank line if no other ports are available

 

[TMGT]

Is this a subframe mounted BH?Do you need to be able to operate the 3pt with the BH installed?
If not you can just rout the outlet of the valve into the 3pt inlet. You can lock out the 3pt lever if it makes you feel better.

This is how Kubota plumbed the BH65 and I believe the BH77 that was factory for B3200

 

[JCC]

The BH is subframe mounted and the 3PH is never used when the BH is on, the 3PH arms are removed.

It would certainly be simpler to just connect the BH output to the 3PH. Being a hydraulic noob I have been looking to do things "by the book".

If I hook up the BH output to the 3PH will the possibility of damage from high pressure back-flow occur only if both the BH valve and 3PH are operated at the same time or is using the 3PH alone a cause for problems?

I know I would never use the 3PH lever when the BH is attached but I worry about someone else doing it and I do not what to start drilling holes in the tractor for a lockout. It would be physically kind of hard to do both levers at the same time without 2 people.

If I go the BH PB to 3PH route would that not effectively be doing the same as above since to enable the BH PB port the output port is plugged and putting a line back to the tank from the output port would not be doing anything since it is plugged?

I really do not understand this put a plug on the output port to enable the power beyond port unless there is some kind of relief valve which somehow opens up the output port even when it is plugged to allow flow back to the tank. How does that whole plug the output thing work? I have seen it in other spool valves but do not quite understand it.

 

[oldnslo]

The BH is subframe mounted and the 3PH is never used when the BH is on, the 3PH arms are removed.

It would certainly be simpler to just connect the BH output to the 3PH. Being a hydraulic noob I have been looking to do things "by the book".

If I hook up the BH output to the 3PH will the possibility of damage from high pressure back-flow occur only if both the BH valve and 3PH are operated at the same time or is using the 3PH alone a cause for problems?

I know I would never use the 3PH lever when the BH is attached but I worry about someone else doing it and I do not what to start drilling holes in the tractor for a lockout. It would be physically kind of hard to do both levers at the same time without 2 people.

If I go the BH PB to 3PH route would that not effectively be doing the same as above since to enable the BH PB port the output port is plugged and putting a line back to the tank from the output port would not be doing anything since it is plugged?

I really do not understand this put a plug on the output port to enable the power beyond port unless there is some kind of relief valve which somehow opens up the output port even when it is plugged to allow flow back to the tank. How does that whole plug the output thing work? I have seen it in other spool valves but do not quite understand it.

The power beyond plug isolates the tank port of the valve from the power beyond function. Removing this plug makes the power beyond common to the tank port. Pressurizing the tank port on most mobile valves will cause the seals on the ends of the spools to leak and worst case crack the valve housing.

My 2 cents route the return line directly to tank and you have no concerns of damaging of the Back hoe valve.

 

[TMGT]

The plug is internal to the valve, maybe that's causing some confusion.

As for how I have mine run with the OUT connected to the 3pt without PB is based on how the factory BH is plumbed on my B series. I've never had an issue with accidentally operating the 3pt and it would require it being held in the raise position once the lift arms reach the end of their travel to provide back pressure on the BH valve but I can understand your concern.

I believe kubota offered a lockout for the 3pt that was just a knob that slid and could be tightened down, similar to the stops on the models with position control.

As stated you can also just take the 3pt out of the equation since it isn't needed by having a 3rd hose connected to the tank and hooking the BH return to that and leaving the 3pt IN line disconnected.

There's a few different ways to hook it up and all will work, I just went the simple route and only have 2 lines for my BH hookup.