Installing 3rd Function Hydraulics - Electric over Hydaulic

[matoyan]

Hi,

I am installing my 3rd function this weekend and I wanted to know if I could hook up the new hoses to a snow plow that has SA cylinder? It's an old plow that has two cylinders, one on each end of the plow or do I have to install a DA cylinder? We have another snow storm due to hit us on Monday and it would make life easier for me to move the angle of the plow using hydraulics instead of physically man handling it. Thanks.

 

[aczlan]

Hi,

I am installing my 3rd function this weekend and I wanted to know if I could hook up the new hoses to a snow plow that has SA cylinder? It's an old plow that has two cylinders, one on each end of the plow or do I have to install a DA cylinder? We have another snow storm due to hit us on Monday and it would make life easier for me to move the angle of the plow using hydraulics instead of physically man handling it. Thanks.

The two cylinders connected to the plow act as one DA cylinder. Hook one DA hose to each cylinder and you should be good to go.
If using your loader valve's bucket curl/dump circuit, you might have to play with how far over it needs to go as the "regen" mode may not work.


Aaron Z

 

[matoyan]

I finally got my 3rd function installed today. Thanks to Irsmun and JJ for all their help and guidance. It really wasn't as hard as I thought. The most difficult part was stopping all of the hydraulic leaks from the connections. I still have one tiny leak, but it's really hard to get to. I'm going to wait until the weather warms up a bit. My fingers were numb from the cold weather and the snow on the ground. I hooked up my snow plow and it works great. I just need to order a grapple now. I connected the switch to my dash and when I upgrade to a joystick, I'll move it. I just have to get wire protectors to make sure nothing happens to them.

 

[AaronS]

Thanks so much for such a great and detailed write-up! I'd like to do this to my L3400 to angle a snow-plow and hopefully one day power a grapple, and now I feel that I can do this myself.

 

[irsmun]

matoyan, good job. I had a heck of job getting all the leaks sealed. The guy a discounthydraulics.com told me I did not need any type of sealer unless I was taking them on and off, on and off. I did not find that to be true. I used high pressure pipe sealant and it worked great.

I have had mine on for a few months now and my only disappointment is that I cannot do all the functions (lift, curl, open or close) at the same time. That is something I wanted to do and why I went with this set up. Its not a problem with the design as much as it is tractor hydraulic pumps in general. 11gpm's at a few hundred rpms doesn't give you enough flow to share. You'd have to rev it to PTO speed to do it and I don't get that aggressive using the foot throttle usually.

I am glad this thread is helping. I drove JJ crazy before I took the plunge. It is getting a little crowded though with other chatter. Oh well, all the info is at the front.

 

[J_J]

Do you understand why you can not use lift, curl, and grapple at the same time using the 3rd function valve?

 

[irsmun]

I do understand. I need more gpm's so there is enough hydraulic fluid and pressure to share. When I have it reved up at high rpms I can do multi functions as long as I'm not 100% on any one. But most of the time I'm operating the grapple with low to medium rpms with the foot peddle. Like I said, I don't slam it down all the way to get 2100 or so. Its not practical to set the hand throttle since you are stopping and starting a lot using the grapple.

I'm sure it also has something to do with the loader control valve and its rating. When I'm not feeding it its max (12gpm?) then the functionality of the valve has different properties with lower hydraulic flow. I guess its like if you used a 50 gpm valve with a 12 gpm pump. I see why you recommend people go with the diverter. For most people, they will get the same functionality...at least with a grapple.

It was one of my basic misunderstandings from the beginning when I was going over this with you. I thought 11 gpms and 3000psi was a constant. I did not realize that was only at max engine rpms. How nice it would be for the pump to be operating at max without regard to the engine rpms. Then you could idle and do all your hydraulic work...but the power would still have to come from somewhere. You would need a super efficient pump that could put that out at 800 rpms.

 

[J_J]

Some people don't understand the flow path and GPM's when trying to use more than one spool or valve at the same time.

On a tractor, it is rare that you need to use more than one spool or valve at the same time. A few seconds will not destroy your operation when selecting different spools or valves. .

Even the guys at WR Long do not understand the flow through the 3rd function. What they say is that when using total flow to the cyl, that there is flow from the PB port going through the 3rd function. There is no flow to the PB when full cyl flow is being used. When the relief is activated, the flow is also diverted to tank.

I am not sure he realizes that if all pump flow is going into a cyl, there is flow coming out the cyl, but, it is going to tank, and nothing goes downstream until you let off the lever, and then the pump flow now passes through the PB port for downstream use.

It doesn't take but a few seconds to fill a cyl and you are ready for the next spool operation.

When using a solenoid valve with subplate, all flow exits the T port including the cyl flow and pump flow.

Downstream valves, when fully activated, will affect all valves up stream by the back pressure generated, as that fluid is competing with the pump flow.

If you could use all spools in parallel, what would happen would be that the hyd component requiring the least pressure would operate first and when that component is satisfied, the next hyd component will operate. If more that one hyd component is equal, then the flow will divide.

Loader valves with a parrallel setup can use two spools at the same time, and the flow is divided.

If you half loader spool, you can also use the 3rd function at the same time, such as loader lift and grapple.

 

[matoyan]

Hi J_J

I bought a brantly backhoe for my John deere 750 and I wanted to know what's the best way to get hydraulics to the backhoe? I have a 3rd function installed already for the grapple and the snow plow. Thanks.

 

[J_J]

Is your tractor open center hyd?

Do you have any hyd at the back now except for the 3pt?

Do you have a hose going to the back for the 3pt?

You could add a remote to the back with PB and use the PB from the remote valve to power the BH

It might be as simple as adding the valve in series with the 3rd function valve and putting a QD on the remote valve PB line. Your BH would then plug into the PB QD.

When not using the BH, the QD would connect to the 3pt.

Show some pictures of the right side and back side.