Backhoe Hydraulics for Backhoe

[herringchoker]

Now I see where the Ford guy is coming from...your tractor pump puts out 26 GPM and your backhoe valve is designed for 14 GPM. I'm no hydraulics expert, but it seems to me that would put quite a restriction in the circuit.

 

[MadReferee]

Well, now it makes a little more sense. It always helps to have the entire set of specs and circumstances.

First of all, I would never plumb the backhoe before the loader valve, even if the loader valve didn't have power beyond. Since you never activate the backhoe valve and loader valve together, the loader not having PB is a non-issue.

With the backhoe having less flow capacity (it will still flow but heat might be an issue) the diverter option or simply breaking the circuit and installing the backhoe only when needed (manual diversion) is starting to sound better.

 

[jgbanshee]

Well about 30 posts before this one the 9-14 GPM spec was listed. That is why I had so many talks with Ford people and post on here and was not completely understanding. So I would have two choices to go with now.

One being, plumb the backhoe and loader in series with a diverter valve that transfers excess flow back to the reservoir.

Two being a selector valve that I would have to throw the valve on to use either the backhoe or loader.

Anyone have any opinions on the first one being a bad option?

 

[MadReferee]

Well about 30 posts before this one the 9-14 GPM spec was listed. That is why I had so many talks with Ford people and post on here and was not completely understanding. So I would have two choices to go with now.

One being, plumb the backhoe and loader in series with a diverter valve that transfers excess flow back to the reservoir.

Two being a selector valve that I would have to throw the valve on to use either the backhoe or loader.

Anyone have any opinions on the first one being a bad option?

Hey, 30 posts ago is a long time.

As for option one, I don't think there is such a thing that "diverts excess flow". All the common diverters I have ever seen diverted all flow to whichever output was selected. You would want something like a splitter or metering valve that will take the full flow and split it between 2 outputs. Keep in mind that this can't be done simply with a valve. Since fluid will take the path of least resistance some type of metering will have to be done inside the splitter. Maybe the valve the dealer suggested does that, but before I spent any money on that suggestion I would want to see the spec sheet on what he is proposing to see what it "really" does.

 

[jgbanshee]

Again I misused the word diverter, I mean divider. Im looking through a Surplus Center catalog and found dividers that have Max Input of 30GPM and divide the flow to two outputs ratios like 2:1. The one I found has a priority "A" that is adjustable from 2-14GPM and the excess will flow out "B." The only thing is that the ports are 3/4" NPT and not 1".

Surplus Center Item Detail

 

[MadReferee]

That will work. You have to plumb so that the loader valve is first, the flow divider is second and the backhoe valve is last. This gives full flow to the loader and whatever you have the divider set for to the backhoe.

Where is the 3pt in all this? It's hard to make out the earlier diagram.

 

[jgbanshee]

Good. The 3pt hitch on this tractor has its own hydraulics system seperate from the front mount engine pump.

If I use the divider valve and direct fluid from outlet "B" on divider valve back to the reservoir can I TEE that into the same return line that will come from the backhoe outlet.

 

[montejw]

Well about 30 posts before this one the 9-14 GPM spec was listed. That is why I had so many talks with Ford people and post on here and was not completely understanding. So I would have two choices to go with now.

One being, plumb the backhoe and loader in series with a diverter valve that transfers excess flow back to the reservoir.

Two being a selector valve that I would have to throw the valve on to use either the backhoe or loader.

Anyone have any opinions on the first one being a bad option?

I'm not trying to dispute what MadReferee has been saying, just adding my 2 cents worth, and maybe just saying the same thing a little differently.

The outlet from the loader valve (open center, no power beyond) is all flow IF nothing is plumbed after the loader valve. If you plumb the backhoe in series after the loader valve in the loader valve outlet line you will be able to operate the backhoe if the loader isn't being used at the same time. However you will be restricting the flow through the loader valve because your backhoe valve is only rated at 14 gpm. That's all the flow you'll get through the loader valve even if the backhoe isn't being used.

If you use a diverter, it's plumbed between the pump and the valves, giving full flow to whichever the diverter is set to select.

If the loader valve has power beyond the backhoe is plumbed to the power beyond line, and the outlet line is still going to the tank.

The 3 pt hitch is the last thing plumbed no matter as it dumps to the tank directly. At least you can't easily get to the outlet in any case. Plumb it to either the outlet of the backhoe or loader, whichever is second. Or plumb it to the power beyond of the last thing if that's what's there.

Monte

 

[MadReferee]

Good. The 3pt hitch on this tractor has its own hydraulics system seperate from the front mount engine pump.

If I use the divider valve and direct fluid from outlet "B" on divider valve back to the reservoir can I TEE that into the same return line that will come from the backhoe outlet.

I don't see why not, unless I am missing something.

 

[MadReferee]

The outlet from the loader valve (open center, no power beyond) is all flow IF nothing is plumbed after the loader valve. If you plumb the backhoe in series after the loader valve in the loader valve outlet line you will be able to operate the backhoe if the loader isn't being used at the same time. However you will be restricting the flow through the loader valve because your backhoe valve is only rated at 14 gpm. That's all the flow you'll get through the loader valve even if the backhoe isn't being used.

Yes, if the flow is restricted by any valve then your flow can only be that value.

If you use a diverter, it's plumbed between the pump and the valves, giving full flow to whichever the diverter is set to select.

Correct.

If the loader valve has power beyond the backhoe is plumbed to the power beyond line, and the outlet line is still going to the tank.

Yes. The loader's PB outlet line goes to the backhoe and the tank outlet line goes to the tank. PB valves have 2 outlets so you must be specific as to which you are talking about.

The 3 pt hitch is the last thing plumbed no matter as it dumps to the tank directly. At least you can't easily get to the outlet in any case. Plumb it to either the outlet of the backhoe or loader, whichever is second. Or plumb it to the power beyond of the last thing if that's what's there.

According to the poster, the 3pt has its own circuit (see above).