That is correct, the idea was to have pressure readily available to operate cylinders. This is why a couple of us have mentioned about getting power beyond the "Diverter Valve". I wish it was not so long ago that I would better remember how it was all plumbed?
I do remember that the quick couplers always had pressure on them meaning I had to shut the engine down to couple or uncouple the hoe as we used it ro run a wood splitter. So it may have been teed in before the loader valve assembly? By doing that and having a Diverter Valve on the outlet of the hoe valve body. You would always have pressure ready for use.
At least this is what I remember of it??

Drujinin, would I even need a diverter valve in this case? Couldn't the pressure be routed straight into the blade control valve??

The problem with using closed center valves (if they are) in a gear type pump system is, the valves do not return oil through the valve body when in the neutral position, instant hydraulic lock, unless you have a relief system for the oil something has to give, valve bodies, hoses, pump housings are subject to max pressure, that is why the JD pump destrokes itself to maintain pressure, not volume, until called upon to do so. A gear pump can not do that, relief valves are not the answer because you are at max pressure and max volume, you will be able to cook off that oil tank in no time flat, a pilot operated flow portioning valve(diverter valve) that operates by downstream pressure, (A manual push/pull diverter valve will not do the job) would be the same as opening a valve to vent pump pressure/volume back to the tank when the hoe control valves are not actuated and then closed instantly when a demand is made. Your blade control valves should be open center, the oil flows through the valve body in a loop to the tank with very little pressure until a demand is made, the portioning valve would have to go after the blade valves but the blade valve relief would still effect both the blade and the hoe. I have never been a big fan of the JD hydraulic system, the radial pump is a problem, destroke valve is a problem, just too much stuff and too much problem and like druginin said, you have to shut down the tractor to plug in hydraulics and the couplers on all models seem to leak constantly and the pre-pioneer JD couplers with the ball, are worse yet. Tad

Yes, what TAD said.
But he explained it alot better than I could have.

As I said, I know little about hydraulics. So what I have done is contact Pape, the S. Oregon J-D dealer and have requested they let me know if the "OUT" labeled port on the hoe is a power beyond port. If it is, it makes sense to run the line from the pump straight into the hoe, and then run a high pressure line back from the "OUT" port to the inlet for the blade controls. Does this make sense? I'm attaching a couple pictures that show the controls on the hoe.

Drujinin, I don't mean to be stepping on your toes here.
4D2Ken, I believe the port marked "out" is simply a return to tank or exhaust if you will, there should be the same thing on the other end of the valve body, that won't tell you if your valves are of the closed center variety, the fact that I can not see a relief valve in the end cap assembly but there appears to be some built into the individual valves indicates "closed center" Remove both quick couplers or what ever connectors there are from the two supply hoses, apply compressed air to one, if it comes out the other, the valves are open center,you could do as you suggested, if not, proceed very carefully. Tad

I'm not in to John Deere stuff but that looks like typical open circuit hydraulics to me. Load check valves in the center (under the plugs). Circuit relief valves under the plugs top and bottom. With that plug in the "out" port there probably is an anti-cavitation check valve in the housing that supplements the flow to the boom and swing cylinders, otherwise flow would be directed to the reservoir. I wouldn't mess with that.
See if you can get a flow schematic for that set up.

I sort of recognize that blade control valve, can you post a couple more pictures from top and far side. Appears to be three valve unit, we're looking at inlet side, pressure relief valve to the right, power beyond plug should be on opposite side.

I was just trying to say that your explaination shows far more expertise on the subject and wanted to "Thank You".

OK. Tad, it appears you are probably correct; the OUT port that is plugged has the same on the opposite side of the hoe control and is where the return line to the hydraulic tank is plumbed in. Well that's a bummer because they only needed one return line port and could have set the hoe up with an available high pressure point.

Old Magnet, here are a couple more pictures of the blade control valve. It has Gresen and what looks like Minneapolis embossed on the top (part of the Minneapolis is gone).

So now I'm really confused. We tried to run both the blade and the hoe by putting a T in the line coming from the pump but that didn't work as the blade and hoe have/need different pressures to operate. I spoke with a tech at Grainger who suggested a 2 spool tandem center control valve (P/N 6W566) to switch between high pressure for the blade and hoe. But it costs $400 bucks! Gaa

I'm getting more tempted to install two ball valves and hose clamp one open, one between the control on the hoe and one between the control on the blade. The tech at Grainger couldn't guarantee that the diverter valve (P/N 6W567) would prevent hydraulic lockup. What to do, what to do...

There is no reason that you can't run the hydraulics in series ( bad business to tee hydraulics) if the hoe valves are open center, so it is imperative to find out what you have, either by schematic as Old Magnet suggested or by flow testing. Being a huge AC fan myself and also an HD7 owner, how about some pictures of that marvelous machine. (they can't tar and feather you over the internet:lol:, not yet anyway, and I am sure the fellows over at the AC forum would certainly be interested) Tad