Main PTO-Possible to switch direction of flow and flow rate?

[PowerTracManiac]

My PT1460 has a switch on the dash to turn the Main PTO flow on and off. That is the extent of my control. Whatever direction the flow is in "is what it is".
Has anyone made up a 3 way switch that would allow for flow in one direction when switch is in up direction, then no flow when switch is off in the middle position, then flow in the other direction when the switch is in the down position?

I recently bought a sickle bar mower and there is a small 12 volt solenoid switch that works to change the flow from the sickle bar mower motor to the cylinder that controls the arm of the sickle bar. This switch works great to control the flow through a block where the hoses are attached. The switch does not give you flow rate control.

The quick attach lever on the tractor does the same function as switch would for the smaller hoses that connect to the quick attach cylinder. With the added bonus of flow control depending on how much you activate the lever. (On/Off/Direction of flow and flow rate)

Seems like a 3 way switch of some type with/without a flow control would be a very nice feature for the main PTO also?
Not a hydraulics expert by any means but want to learn how this might be done?

 

[oldnslo]

What you are describing in the function of a 4 way - 3 position valve. Mobile versions may be called 6 way - 3 position since have flow path for power beyond.

Things to consider when applying a valve:
Flow rate of system. GPM or LPM
pressure in system PSI or Bar
Function: operating a cylinder or motor.
Is float or regenerative circuit required
Etc..

Not sure what style would be required on your power trac.

 

[m5040]

My experience is the PT's hyd run hot and every fitting or valve would add some restriction and more heat. What implements would need to be reversed?
It wouldn't be too difficult if you need it, just another sizeable valve and electrics.
I have a similar 12 volt valve on a stump grinder as you describe on your sickle bar. I think it takes backpressure from the cutters hyd motor and when actuated, it uses the back pressure to move the cutter-head right or left. It doesn't direct all the PTO flow to the hyd cylinder. My cutter keeps spinning with power as the head swings.

 

[PowerTracManiac]

Agreed the hydraulics seem to run hot. However a flow direction valve would not increase heat significantly IMHO. The switch would be from off-to a direction of flow-which is what is happening now. Restricting the flow to the larger PTO hoses to slow down an implement and would add significant heat as you suggest.
Truth be told, I am currently running the sickle bar through my lever arm hoses for the quick attach cylinder hoses-so there must be decent pressure at these hoses. Reason being is I can go up and down with the cylinder/sickle bar slowly with the lever arm hoses-pending direction of flow I select for the lever arm hoses. I cannot do that with the PTO switch hoses. If I used the PTO switch hoses for the sickle bar, I would only have on/off flow to the sickle bar and not direction of flow. Therefore the cylinder would only go in 1 direction with the PTO switch large hoses.
Also, currently the cylinder goes very nicely either way with the lever arm control and feathering the lever arm.
The sickle bar cutter works well with the quick attach hoses but I have to keep the speed of the engine up pretty high to get the flow rate needed to move the sickle bar at a decent pace. Also, I have to hold the lever arm up or down to get continuous flow through the quick attach cylinder hoses and have the sickle bar continue to run.
Surprisingly to me, this is actually working very well as I thought the pressure and flow in the quick attach hoses would be too low and too slow to run the sickle bar. I am cutting 1 inch branches coming into the driveway-no problem.
I assume the pressure and flow through the quick attach hoses is significantly less than what I have at the large PTO hoses (I have inquired as to the Pressure and flow specs on these smaller quick attach hoses here on the forum and I also sent an email to PT but I have not gotten an answer back yet).

The reason I am interested in this is because my next attachment is going to be an post hole auger. I will have many large holes to drill and I dont think the lever arm hoses will have enough pressure/flow to run the auger with a large bit. Also would be nice to have forward and reverse for the auger so I can back it out when it gets stuck and possibly other implements I havnt thought of yet?

 

[ponytug]

I did a deep dive on this, and didn't pull the trigger on it. I do have the valves and block, as the parts came with a third party attachment that I plumbed differently.

So, as @oldnslo described, there are valves to do what you want. The not so great news has to do with where your existing solenoid might be, as well as some motor news.

On my 1445, the PTO solenoid is against the tank, so swapping the solenoid block for a solenoid block compatible with three way operation requires either draining the hydraulic tank, or hooking up a shop vacuum you don't like to the filler cap, and hustling. The other potentially not so great news is that some of the PT attachment motors are gerotor type motors that have bad things happen if the flow is reversed.

As reversing flow in motors and lines is almost guaranteed to knock debris loose, when I went down this path, I thought that it would be prudent to plumb a reversible shock pressure compatible return line filter on your return flow.

In the end, I decided it was easier to plumb it in outboard of the the PT PTO connectors, as the filter wouldn't need to be bidirectional, though it would still need to be shock resistant. I have all the parts, except the filter, so the fact I haven't gotten to the project speaks for itself.

YMMV.

In practice for me, the only attachment that bidirectional flow would be really nice on is my wood chipper, as I have only gotten the auger stuck once. I learned how to lower the rototiller and backup, which instantly frees it of rocks.

All the best, Peter

 

[m5040]

I have a post hole auger on my tractor, when it jams I lift the auger up and it frees itself.
An attachment that turns at high speed and then jams with a foreign object may not have a hyd motor that can have reverse flow and start out with enough torque from a standstill to unjam itself. The momentum may have added much additional force.
The addition of a reversing valve, even when in the same flow as before the installation, will have small passages in the spool for the oil to travel through generating additional heat. It is your tractor, I am just saying there will be a downsides.
Can't you just put identical fittings (properly labeled) and switch the hoses on the stock configuration if you jam the implement and can't free up in normal methods? This wouldn't allow toggle switch control of your implements, but would help if you jam them up.
I would have thought your sickle bar motor would have run on the PTO circuit and the up/down run off your quick disconnect circuit.

 

[PowerTracManiac]

I would have thought your sickle bar motor would have run on the PTO circuit and the up/down run off your quick disconnect circuit.

a good solution and suggested by Pony also. I didnt want to spend any more money on hoses at this time. I wanted to make it work with the electrical hydraulic solenoid switch that came with it.

Appreciate your feedback and thoughts on the heat and other suggestions!