Do any 3 pt hitches provide downforce?

[CobyRupert]

Thanks for explanation.
I was thinking that when one SCV port is sending pressure, the other port is open to return to tank, so if 2nd hose is outlet from relief valve on kit, it seems the same as being hosed to the fill port?
Does the act of raising the 3 point hitch retract the downforce cylinder (without operating SCV lever)? If so, it makes sense that 2nd hose need to go directly to unrestricted fill port.
...but doesn’t that mean when the 3 point hitch is raising mechanical leverage pushes the cylinder to retract with enough force to force oil through relief valve so cylinder can retract? Otherwise it wouldn’t retract right?

 

[Bavarian]

Put the service control valve in float position and both ports are internally connected to the tank. Then there should be no binding while raising the auger.

 

[MtnViewRanch]

Put the service control valve in float position and both ports are internally connected to the tank. Then there should be no binding while raising the auger.

You are correct. The problem is you have to have an SCV that has the float feature. Most do not have that feature.

 

[MtnViewRanch]

Thanks for explanation.
I was thinking that when one SCV port is sending pressure, the other port is open to return to tank, so if 2nd hose is outlet from relief valve on kit, it seems the same as being hosed to the fill port?
Does the act of raising the 3 point hitch retract the downforce cylinder (without operating SCV lever)? If so, it makes sense that 2nd hose need to go directly to unrestricted fill port.
...but doesn稚 that mean when the 3 point hitch is raising mechanical leverage pushes the cylinder to retract with enough force to force oil through relief valve so cylinder can retract? Otherwise it wouldn稚 retract right?

Without writing a book to explain this, you only apply the scv pressure for going down. This can be a constant pressure with the excess going out the relief valve. When the hole is finished you let off the scv. Raise the 3pt and the rod retracts pushing the oil out through the by-pass valve.

So yes, the 3pt is what forces the rod to retract and the oil is forced out through the by-pass valve to the tank.

 

[CobyRupert]

When I bought my used PHD, previous owner had SCV fittings on both hoses. It didn't work, I figured out why, then I forgot why.

Yes, the ole' brain cells woke up after a few years and it FINALLY dawned on me there's no way to retract (single action) cylinder if 2nd hose is connected to SCV port....regardless if operating SCV lever is required for retraction or not....that is: Trying to retract using SCV lever with 2 hoses to SCV you'd be putting pressure to the outlet of relief valve even though you're giving (single-action) cylinder a path back to tank. And if you don't use lever, all paths are closed = no retraction. Dooh!

...but it seems 2 hoses connected to SCV should be able to extend cylinder...but just once and then you're stuck extended.

 

[MH8675309]

A good auger with decent teeth should work well enough without down pressure. I usually have to start the hole with a hand digger otherwise - like others have said - it wount bite in to the ground. I usually am working by myself so it means getting up and down off the machine but once the hole is started the digger will go in decently at an idle. One thing to do is go slow going in so that the ground pulls on the auger keeping it fairly straight up and down. Our dirt is clay about 6 or 8 inches down below the topsoil and is tough work to do with a hand digger - I've done many by hand and a good working auger is a God send.

 

[Bavarian]

Without writing a book to explain this, you only apply the scv pressure for going down. This can be a constant pressure with the excess going out the relief valve. When the hole is finished you let off the scv. Raise the 3pt and the rod retracts pushing the oil out through the by-pass valve.

So yes, the 3pt is what forces the rod to retract and the oil is forced out through the by-pass valve to the tank.

You are talking about the pressure lelief valve that's in the primary circuit. I've never seen a SCV on a tractor that's equipped with a secondary valve.
If you put the SCV in neutral, both ports are closed. Otherwise the equipment would dump/drop.
The primary relif valve sits on the pump side and sealed is away from the closed ports.

 

[MtnViewRanch]

You are talking about the pressure lelief valve that's in the primary circuit. I've never seen a SCV on a tractor that's equipped with a secondary valve.
If you put the SCV in neutral, both ports are closed. Otherwise the equipment would dump/drop.
The primary relif valve sits on the pump side and sealed is away from the closed ports.

No, I'm talking about the relief valve that is on the PHD to accommodate the down pressure unit. The relief valve comes with any and all PHD down pressure kits that I know of.

 

[Bavarian]

No, I'm talking about the relief valve that is on the PHD to accommodate the down pressure unit. The relief valve comes with any and all PHD down pressure kits that I know of.

Ok. Didn't know that.
But then the relief valve needs its own connection to the tank. Makes sense.

I just thought about the situation for a while. If the down pressure is set up like in the picture, it should be possible to lower and raise the PHD with the down pressure cylinder only, as long as the 3 PTH is in the lower position. And the cylinder is extended/retacted by the SCV.

 

[MtnViewRanch]

All I can say is that they have it designed this way for a reason. The system works very well.

You can't screw it up when set up and used how it is designed.

No good reason to reinvent the wheel here.