Backhoe Adding Backhoe Hydraulics

[ptrotter]

I am installing a Woods BH-80 on my B7800 and have a question on the hydraulic connections. I have a single rear remote valve on the tractor so the backhoe connection is a little different than normal. I believe I can connect the backhoe hydraulic input to the power beyond port on the remote valve and the output to the PB port on the engine, effectively putting the backhoe in series with the loader valve and remote valve. These hoses would then be connected together when the backhoe is removed. I was wondering if, as an alternative, I could stack a 2nd remote valve with a detent and connect the backhoe to that valve and keep the valve in the detent position when the backhoe is in use. This would make for a neater installation if it would work. Has anybody done anything like this?

Paul

 

[rScotty]

Has anybody done anything like this?
Paul

Well, I've done something sort of like that. On your original plan, explain again where you would plan to plumb the output of the backhoe?

My open circuit type loader control valve on an old JD is a replacement made by some US company (I got it surplus) and came with several inserts for the the power beyond port. The one I chose theoretically allows the full hydraulic flow to go to the PB port and thence on to any other implement...if anything is plumbed there, otherwise the flow stays in the loader control valve where it is either metered to the cylinders or returned to the sump.

If the PB port was used it could allow the hydraulic flow to go to the backhoe where the flow would then be used in the same way and returned to the hydraulic sump. In the real world, how much of the flow actually ends up going to the backhoe and residual flow is still available to the loader is entirely dependent on the flow rate of the pump and the fluid resistance of the whole system.

The downside of plumbing the backhoe through the loader control valve PB port is that unless the tractor has a huge hydraulic pump or some way of turning off the flow to the backhoe then you have just effectively bypassed the loader. I think that might be what you are trying to avoid?

As to your second question...Yes, I have run implements
- in fact I still do - by tying down the lever in the full flow position just like you are thinking of doing in the second scheme. I use a bungy cord which lasts about a season. The only problem is that the additional fluid resistance of running the oil through the unnecessary valve body makes a screeching noise until the oil warmed up and lost viscosity. Obviously that isn't good for the valve, but so far it hasn't given up. So it works, but isn't so great.

You probably know that there are flow diverter valves that do the same thing with a simple lever and are way better because the fluid resistance is low. There are also adjustable "demand-type" flow diverter valves where flow will automatically go to a second circuit when the flow to the first circuit is satisfied.

My recommendation? Go with quick disconnect hose connectors. That's the easy way.
rScotty