Home brew 3rd function questions

[ericm979]

I'm going to get a grapple for my Branson 3725 and will probably make the 3rd function setup myself. It's looking like the loader's torque tube may be the best bet for locating the solenoid valve. The other possible locations are under oil filters or block access to the fuel filter and engine dipstick. The disadvantages that I can see are that it's more likely to get damaged, and I have to run long hoses out to it and those will carry pressure all the time as they're P and T lines. The valve would be in line between the dealer installed rear aux valve and the factory rear aux valves whose T line goes to the 3pt. The 3725 puts out 10.3 GPM. The charts I've looked at would indicate 1/2" hose for 10gpm. But the dealer installed 3rd rear valve has 3/8 between it and the loader valve. Should I use 1/2" to my 3rd function valve? Should I replace the dealer installed lines with 1/2"?

I realize that putting the valve on the torque tube puts it out in harms way, I will probably make a guard to keep branches from poking it.

The P and T lines to the 3rd function valve will have couplers roughly where the loader valve couplers are for removing the loader. I will make them so that they can be connected together to bypass the 3rd function. I'm a little worried that I or someone else (future owner) would disconnect the loader and forget to connect the bypass. Which would make the system deadhead. Does deadheadding for a few minutes until you figure out what's wrong hurt anything? If so are there connectors that would automatically make that bypass when disconnected?

One more dumb question. There's two kinds of solenoid valves I see- one central box for the electric connections like this:
D3 HYDRAULIC VALVE TANDEM CENTER 12 volt DC
or two separate boxes like this:
D3 HYDRAULIC VALVE TANDEM CENTER 12 volt DC

What's the difference? Is there anything in those boxes?


BTW thanks to guys like N2Dfire and aerojunkie who have posted their home brew third function process and everyone who helped them out.

 

[Xfaxman]

I have no experience with this, but from what I have read I think you need this kind: Hydraulic solenoid operated selector diverter valve 12 volt DC - Fremont Industrial Supply

 

[LouNY]

The pieces that you have mentioned in your post are electrically operated hydraulic control valves when activated you will get full flow instantly
and be slamming your grapple shut and open with no ability to modulate it and gently close or open it, the seconds posting is more like what most
people would use the two supply ports would be plumbed to your existing usually bucket curl lines with the two normally open ports piped to your
bucket curl and the other two normally closed ports to your grapple, to use it you would activate your switch to operate the valve then using
your curl valve operate your grapple releasing the switch to go back to your bucket curl function.

 

[ericm979]

People use both 3rd function and diverters for grapples. At 10 gpm it'll take about half a second to open or close the grapple If I did the math right. It's probably less than the 10gpm the pump produces at that point but I don't know how much less. I was figuring that I could put adjustable one way restrictors in the A and B lines to slow the grapple's response if it is fast.

The ergonomics for the diverter seem like they'd be weird to me. Also you can't curl the grapple and close it at the same time.

If I went with a diverter most of my questions are moot as it's not in the main circuit.

I could be fancy and get a porportional control valve along with the appropriate switch and control board. It's probably expensive though.

 

[LouNY]

It will work that way, and true using a diverter you can't curl and clamp at the same time,
on my 8050 I ran a pair of hoses from one of my rear remotes for my front auxiliaries.
The only thing is having to move my hand from the loader joystick to the remote lever.
View attachment IMG_20171008_135654348.jpg View attachment IMG_20171008_135741142.jpgView attachment IMG_20171008_135710673.jpg

 

[bindian]

I have no experience with this, but from what I have read I think you need this kind: Hydraulic solenoid operated selector diverter valve 12 volt DC - Fremont Industrial Supply

View attachment 524037

This style valve is what I have to operate my grapple and auger on the front loader. I also have a similar setup running the thumb on my 15,000 pound excavator. Plumb the lines into the bucket curl and dump lines. Then you only have to move your finger or thumb on and off the loader's joystick button to move the grapple. Moving one function at a time is no problem. Plumb the grapple lids to close with the same curl movement of the joystick and open the lids with the same movement to dump, you only have to move your finger on and off the button to close the grapple lids or tilt the grapple up. I've been using my grapple for 5 years this way and there second nature with no learning curve when I run my thumb on my excavator.

Also, grapples only need 1/4 inch lines to operate a grapple. 3/8 inch lines at most.
hugs, Brandi

 

[kennyd]

My opinion FWIW is that a true 3rd function valve should be mounted on the tractor, not up on the torque tube of the loader since the P and T lines are flowing constantly. Yes, deadheading the system for “a few minutes” can damage the system if the PRV (pressure relief valve) is not working 100% and the fluid may overheat as well.

 

[N2DFire]

Hey Eric,

Thanks for the props already. I'm just glad the information has been helpful to others.

For your situation as far as mounting location if you're thinking Diverter then the torque tube might not be *that* bad just be sure to mount it as protected as you can (a guard is a great idea). If you're going 3rd function then I would try to find somewhere much closer to the "core" of the tractor (and more protected) - I have even seen some set-ups where the valve was mounted on the rear of the tractor (near the top link mounts) and some under the hood just behind the "firewall" The biggest issue is being able to route the hoses.

As you probably already read, I used 1/2" for the P & T lines between the loader valve, 3rd function valve, and 3pt on the tractor & then 3/8" lines to the torque tube for the grapple. This restriction will slow the operation of the grapple down some by itself. You can also add flow restrictors if more reduction is needed.

As to your question about the different valve wiring - I used the top single box style and there's nothing inside there except the screw terminal for ground and the two positive terminals (one for each coil) - the only real advantage I can see is not having to run a separate ground wire to each coil on the dual connector style (and possibly any size / orientation issues)

As the old saying - to each their own but personally I would not make the 3rd function "bypass-able" - I would plumb it in series somewhere between the loader valve and the 3pt like the other aux valves are already. I would put disconnect on the lines to the torque tube where ever your factory loader disconnect valves are.

The only other advice I can offer is design it over and over on paper & in your head before you start. Measure everything twice & then measure it again. Make sure you have all the little fittings to go between everything. You'll still run into some gotcha somewhere but hopefully with good planning it will be minor.

Best of luck and don't be afraid to ask questions.

 

[ericm979]

Thanks! I learned a lot from your writeup. I agree that the tractor's the best place for the valve but I'm having a hard time finding room where it's not in the way of something or under an oil filter. Last night I figured out a really clean way to do a diverter by breaking into the curl circuit's hard pipe tees out on the loader. But after reviewing a couple threads about diverter vs true third function I'm still thinking the true 3rd would suit me more.

 

[Xfaxman]

Here is a good explanation that I bookedmarked a long time ago for future reference: http://www.tractorbynet.com/forums/...ppling-fun-picture-thread-13.html#post4299680

 

[N2DFire]

I found the write-up I was thinking about where they installed a W.R. Long 3rd function kit.

Check out the first picture in this post and see how the mounted the solenoid off the rear of the tractor. Maybe this is something that will work for you.

http://www.tractorbynet.com/forums/kioti-owning-operating/331759-3rd-function-install-summary-dk40se.html#post4052068

 

[ericm979]

I finally got around to testing my tractor and when I am moving the loader the SCVs don't get any flow at all (or at least not enough for the tilt cylinder to raise the box blade). 3pt doesn't get flow either. I think my loader valve sends everything to the tank instead of power beyond. I would prefer a 3rd function for ergonomics. The idea of having to move the curl to position the grapple then
return to center, press the diverter button and move the lever again seems like something I'd have a problem with (like forgetting to center the lever between diverted and not diverted). Having separate controls even if they are buttons makes more sense to me.

But with this loader valve I'd have to stop moving the loader before I could open or close the grapple. With a diverter I could theoretially raise or lower the loader while opening or closing the grapple if I can get my brain to do it. Its too bad the 3rd function wont' work as I found a good place for the valve under the seat where the gear shift would go on a gear model.

I have an email into the dealer to verify how I think the loader works and to double check that the curl doesn't have regen (the factory 3rd function is a diverter so I think not).

I think I can make a clean setup with the diverter by disconnnecting the hard lines from the tees that feed the curl cylinders on each side. Those are out on the loader near the torque tube so I'd only need short hoses to a diverter located out on the torque tube.

 

[N2DFire]

With a diverter I could theoretially raise or lower the loader while opening or closing the grapple if I can get my brain to do it. Its too bad the 3rd function wont' work as I found a good place for the valve under the seat where the gear shift would go on a gear model.

True - in theory.

The definitive answer will come if you try to Raise/Lower the loader and Curl/Dump the bucket at the same time right now.

On our Kioti, this is possible - BUT you have to feather into both functions very lightly and since they are dividing the available fluid flow - both movements are very slow.

I think you're going to find that on tractors this size & with the style/design of the hydraulic systems the only real difference between a 3rd function valve & a diverter valve is going to be in the ergonomics of the controls (and perhaps a little cost difference).

I ended up doing the 3rd function for the exact reasons you stated - it just felt more natural to me to operate that way vs having to move the loader joystick back and forth. Especially since to orient it the way it "makes sense" you would have the joystick pulled one way to dump and pushed the opposite to open the grapple lid. In my mind that's just a lot of back and forth movement & lots of chances for my uncoordinated self to forget to press/release the diverter button.

 

[ericm979]

The definitive answer will come if you try to Raise/Lower the loader and Curl/Dump the bucket at the same time right now.

It does that but not as well as the Kubota I had. If I push the stick all the way into a corner it'll move the loader and curl the bucket at about the same rate. But I can't feather the curl a little as I'm raising or lowering the bucket. Could be I need more practice on this loader- I'm at 72 hours but a lot of that's been chipping mowing and box blading. Not a lot of loader work until recently.

At pto rpm it'll move the loader and curl the bucket together at a reasonable speed. It's got 10.3 gpm.