power beyond / rear hydraulics gpm?

[sodhead]

Howdy all. Does a power beyond hydraulic connection typically have more gpm capability than a rear implement hydraulic connection would have? You see I have a JD 3120 CUT that has rear hydraulic ports for implements, and also a power beyond kit installed. So basically I have two options for hydraulic connections at the rear of the tractor. I just bought a 3pt mounted hydraulic post pounder so of course I need to tap into a hydraulic feed somewhere and I'm trying to decide if it would be better to use the rear implement connecter, or hookup to the power beyond connecter. I know if I use the power beyond as my pounder hydraulic source I will loose the function of my 3pt while its attached (thats how it is when I use the power beyond to power my backhoe attachment,, but I dont need the 3pt to function with the backhoe so its not an issue there), but I do want my 3pt to work with the pounder so I can move it around. So I thought I'd just hookup to the rear implement port and use a zip-tie to hold the rear implement valve control open to keep flow to the pounder while using it. That way I could have my pounder operational and my 3pt would still operate. But I was wondering,, if the gpm flow of a rear hydra implement connection is alot less than a power beyond hydra connection, my pounder might work slower?

I looked for gpm specs for each but I'm not having much luck. Thanks for any help.

 

[6sunset6]

Whose hydraulic post pounder did you get? I have been looking at them for a while. They seem to need unrestricted free flow back the tank. You might be able to feed it from a remote but the return through the remote might slow down the pounding.

 

[kennyd]

Welcome to TBN

First, the specs on your 3120 are as follows:

Hydraulics

Type Open Center

Pump Rated Output, gpm (L/min.) 13.9 (52.5)

Steering 5.3 (20.0)

Implement 8.6 (32.5)

Pump Type Dual gear

Maximum Operating Pressure (PSI) 2500

Draft Control Type Position control

Remote Control Valves Available 5




So you have 8.6 GPM to work with on your machine, that will power a PP just fine.

Since the PP has it's own valves, the proper hookup is to use the PB connection on your machine. There should be two return on the back of your tractor...One feeds the 3PH(what your "loop" hose plugs into when your BH is not on) and the other goes directly to the tank bypassing the 3PH (what you use when the BH is on). You would simply use the return that feeds the 3PH to keep it operational.

 

[Eric_Phillips]

I am going to go out on a limb and disagree with Kenny on this one. As stated earlier you need unrestricted return for the post driver. The way I plumbed mine was to put a valve between the PB and the driver. The new valve has a PB to the 3PH and the return on the driver goes directly to the filler port in the tranny. So when operating the driver you activate the new valve and all the flow is diverted to the driver and allows the cylinder to dump quickly. Use as large a hose as you can for this. When you need the 3PH just flip the new valve back and the flow goes back to the 3PH. You shouldn't need to run them at the same time but you will need to flip back and forth. A bungee cord or a detent kit on the new valve will both work. Also there probably is not a PB on the driver valve so running the 3PH off the return from the driver may not be the best for the valve.

 

[kennyd]

I am going to go out on a limb and disagree with Kenny on this one. As stated earlier you need unrestricted return for the post driver. The way I plumbed mine was to put a valve between the PB and the driver. The new valve has a PB to the 3PH and the return on the driver goes directly to the filler port in the tranny. So when operating the driver you activate the new valve and all the flow is diverted to the driver and allows the cylinder to dump quickly. Use as large a hose as you can for this. When you need the 3PH just flip the new valve back and the flow goes back to the 3PH. You shouldn't need to run them at the same time but you will need to flip back and forth. A bungee cord or a detent kit on the new valve will both work. Also there probably is not a PB on the driver valve so running the 3PH off the return from the driver may not be the best for the valve.

HOW DARE YOU!

But, after a good night sleep, I have to agree-I did give bad advice because of the need for the unrestricted flow back to the tank...my suggestion would not have provided that.

So you used a manual diverter...not really a valve then?

 

[sodhead]

I knew the return for the PP would need to be unrestricted straight back to the tank from reading other posts about this setup. So I knew if I used the PB I'd loose my 3pt function from not having the return plumbed back to the PB connector and completing the hyd loop. Thanks for the idea of adding a valve Eric, that sounds like a solution if I use the PB for the hyd source, so you can select beteen the two functions (3pt or the pounder)? Yes I think I get it.

So Kenny would that 8.6gpm rating be the same for the 3rd SVC Implement outlets as well as the PB outlets on my machine? The reason I ask is that it seems like in my case maybe I could get my hyd source for the PP from the 3rd SVC outlet, and bungee cord the 3rd SVC control lever into position to constantly feed the PP,, and that way I wouldn't have to break my PB loop and loose the 3pt (or add a selector valve as Eric noted).

6Sunset6 - the PP is a Shaver HD8.

Thanks again guys.

 

[6sunset6]

I think that would work but you would have to dump the return from the PP valve right into the fill port as Eric said he did.
The advantage to this is that you would never dead head the BH loop if you somehow forgot to put the loop back in non BH service .
I assume the PP valve has a return to tank when at rest? Other wise the PB BH loop is dead headed. Not good from what I have read.

 

[RickB]

I knew the return for the PP would need to be unrestricted straight back to the tank from reading other posts about this setup. So I knew if I used the PB I'd loose my 3pt function from not having the return plumbed back to the PB connector and completing the hyd loop. Thanks for the idea of adding a valve Eric, that sounds like a solution if I use the PB for the hyd source, so you can select beteen the two functions (3pt or the pounder)? Yes I think I get it.

So Kenny would that 8.6gpm rating be the same for the 3rd SVC Implement outlets as well as the PB outlets on my machine? The reason I ask is that it seems like in my case maybe I could get my hyd source for the PP from the 3rd SVC outlet, and bungee cord the 3rd SVC control lever into position to constantly feed the PP,, and that way I wouldn't have to break my PB loop and loose the 3pt (or add a selector valve as Eric noted).

6Sunset6 - the PP is a Shaver HD8.

Thanks again guys.

That installation will work just fine, provide essentially equal flow as from a PB circuit, and be the most economical to set up. You will, however, need to return your SCV to neutral to use the 3PT. As stated several times, a zero-pressure return is required in any event.

 

[kennyd]

So Kenny would that 8.6gpm rating be the same for the 3rd SVC Implement outlets as well as the PB outlets on my machine? The reason I ask is that it seems like in my case maybe I could get my hyd source for the PP from the 3rd SVC outlet, and bungee cord the 3rd SVC control lever into position to constantly feed the PP,, and that way I wouldn't have to break my PB loop and loose the 3pt (or add a selector valve as Eric noted).

6Sunset6 - the PP is a Shaver HD8.

Thanks again guys.

That is the best way...You will still get the 8.6 GPM from the remote.