sickle bar hydraulics / Kubota 2620

[TheGreyRider]

does anyone know if I can use the hydraulics on the back of a Kubota 2620 to control a sickle bar mower? The sickle bar only has one connection for lift and it is gravity down. When I don't have the backhoe on the machine I connect the in and out hydraulics together, can I just use one of those for the mower?

 

[J_J]

Use the pressure line and a SA hyd valve for power up and gravity down.


Or a DA valve and plug the B port or run the B port to tank.

 

[Creamer]

Or buy a lightweight double acting cylinder. The sickle bar floats by itself and sometimes a double acting cylinder lets it drop faster.

 

[TheGreyRider]

The sickle bar mower has a hydraulic cylinder now, but only one hose, could I connect another hose to the cylinder, and then run back to my two connections on the tractor? I guess I would need some kind of control. I really have no clue when it comes to the hydraulics.

I also thought about just running that single hose to the front of the tractor and using one of the loader outlets as well. would that work?

 

[J_J]

Yes, that will work,but you still have to do something with the other valve work port.

Is the cyl a DA cyl with two ports or a SA cyl with one port and a breather port?

 

[Creamer]

Loader controls are typically set up for a closed system, i.e. what flows out of one side of the cylinder flows into the other side of the cylinder, i.e. dual acting. Therefore I doubt your loader controls would work.

I picture of the cylinder on the mower would be very helpful showing the two ports.

 

[J_J]

Creamer,

Just what is it that you are trying to explain?

Kubota's do not have Closed Center hyd systems.

Cyl expended fluid flows to tank.

 

[TheGreyRider]

Man you guys are losing me on this stuff. So from what I am reading here the back on the tractor where I connect the hose back to the tractor when not in use is because there has to flow there correct? Like I could not just disconnect that back hose?

The front of the tractor for the loader there are 4 hoses, do they need to be " looped" thru when not in use? Like can I just use one of those?

The hydr cylinder on the mower has a fitting on each end of the cylinder, but only one hose coming out.

 

[CDN Farm Boy]

I'll try a different way to explain for you....

When you mount the BH that loop gets disconnected to hook up the BH. This allows the hyd fluid to go from that loop to the BH valve and then to the BH cyl depending on which lever you pull. Fluid comes out the other side of the cyl back thru the valve and to the other side of that loop. There is constant flow on that loop when the tractor is running that's why you have to reconnect it as the loop when you take the BH off.

If you were to hook your mower cyl to that loop, you would be missing the valve to control it and there still has to be a loop somehow. Since tractors have what's called an 'open center' hyd system part of that is that when the nalve is in neutral, fluid still flows thru the valve from the pressure inlet to the tank return bypassing what are called the work ports which are the lines that go to the cyl themselves.

The simplest thing for you to do would be to get a 'single spool open center valve'. Connect the pressure and return of this to that loop and put a pair of quick disconnects on the work ports giving you one pair of rear remotes. From this you can run your mower or anything else that has a cyl or motor on it. Unhook the BH, hook this valve up and good to go.

 

[Creamer]

I may have confused you - my apologies. I am not real familiar with Kubota loaders but I thought the were closed circuit hydraulics. J_J knows them better than I do and if he says they are open circuit then that is what they are.

If your hydraulic cylinder has a fitting on each end then it is a double acting cylinder being used as a single acting. You should be able to connect another hose to the cylinder and connect it to the tractor and all will be good.

FYI - open circuit means that when you actuate the hydraulics oil is pushed into the side that you want to use, i.e. lift side and the opposite side of the cylinder has the pressure released and allows the oil to flow back to the reservoir
Single acting cylinder is where only the lift side gets pressurized and when you lower the pressure is released and gravity on the mechanism forces the oil out of the cylinder
Double acting cylinder has pressure one one side or the other to move the cylinder and does not need gravity