Kubota L2250 BF400G Loader - adding control for snow plow lift and angle

[Colonel Monk]

Howdy

Last year, I finally got around to making a plow frame to attach an old Western 7.5ft plow to the bucket of 1985 Kubota L2250 Tractor with BF400G loader. Hydro is 2250 psi @ 6.7 gpm.

I never did get the hydros on the plow hooked up, relying on the FEL to raise and lower and manual angle. While it worked, it wasn't a great solution. The lowering was very sensitive, and partly because of how I designed the mount, care had to be taken to make sure there wasn't downforce on the plow. Couldn't just drop it and plow, had to lower it carefully....

So this year, I'm going to redesign that mount so the plow has more natural float, and I'd like to separate the plow's controls for more, well, control.

I have looked plenty at adding a double selector valve, and while I could do that to get the plow angle hooked up via the bucket curl, I have been thinking about instead adding another double spool directional control valve for plow lift/angle in the winter, and thumb and rear grapple in the summer.

To run both plow angle and a plow lift cylinder from existing joystick, I'd need two double selector valves one for lift and one for curl/angle. They are a few hundreds bucks each, so that's not cheap.

To add a second dbl spool valve, looks like I can do that for $100 to $200 bucks.

Can't seem to find a schematic for the existing hydraulic system.

My thought was that the hydraulic return from the existing loader valve could be run to the input of second control valve, and then continue to tank.

Would that work?

There are 3 hoses from tractor to loader. I understand one is pressure send and one is tank return, but what would the third one be? How to identify which hose is which?

Appreciate the help, I'm looking forward to having a better setup this year.

Regards,

CM

 

[Dave M7040]

Of the three hoses, one will be a power beyond line to feed other hydraulic circuits on the tractor such as the 3 pt hitch and any rear remotes.

To identify which is which start by studying the loader valve body for cast in letters like P which will be the supply from the pump, T for the return to the reservoir

You should never use a valve return or tank line as a supply for another valve. Tank or return ports are only rated for around 500 psi so you can end up cracking the valve body.

Power beyond is provided to supply other circuits.

If you want to add another double spool valve order it with the power beyond feature. Usually a special sleeve or plug.

You can daisy chain valves using their power beyond ports

Dave M7040

 

[Colonel Monk]

Dave,

Thanks again, I really appreciate your help! (btw, was able to fix the dragging brakes with your help also)

So P would be pressure, T would be tank? And is there a typical label for Power Beyond?

Far as choosing the new valve, as long as I've got it rated above the system flow and pressure and it's got PB should be fine, yeah?

Thanks

CM

 

[ptsg]

Power Beyond can be label as: N, C or PB depending on the valve manufacturer.

 

[Colonel Monk]

Power Beyond can be label as: N, C or PB depending on the valve manufacturer.

Thanks much. I'll try to drop in today in our barn and get a look at the valve. Time to get the plow rig ready for winter!

CM