Help tapping into HYDRO Kubota b5100

[LazyGator]

I am making a FEL for my Kubota B5100e, in an effort to save costs I would like to use the existing hydraulic pump, in theory I should be able to tap it somewhere for the feed and find a return line to add. I don't know Hydraulics very well at all this is my first time dealing with them, any help would be great.

 

[BeezFun]

Most tractors provide a place to connect to supply and return. There is typically a small block held on with bolts to cover the open ports. You buy a block to replace that cover that has threaded fittings on it that allow you to thread in a hose that goes to the supply/return on the loader valve. That is not a large tractor, it's possible it didn't offer a loader as an option. But it may have provided a way to add rear hydraulics, so look around on the transmission for something that looks like a cover or plug for access to the hydraulic system.

 

[rScotty]

These older compact tractors typically had the hydraulic pump up on the engine, and most of them were plumbed so that the only use for the hydraulics was to feed fluid under pressure to the 3pt lift hydraulics at the rear. Usually via a steel pressure line about 3/8" in diameter.

It was possible to interrupt that line with a "Y"" flow divider block and tap off some of the pressure to run a loader. The block was nothing more than a block of aluminum about 1"x4" threaded and drilled internally to serve as a "Y" type connector. As Beezbun wrote, the factory blocks sometimes also had some holes drilled to mount the divider block to the top of the transmission case.

But all too often this system meant that the ran slow, and worse yet....the 3pt worked erratically. Adding a either/or type selector valve to the divider block allowed just one system to work at a time and that was an improvement....but then you couldn't use both at once. So if one had leaky cylinders, then both suffered.

The best solution on those under 20 hp tractors was for the loader to use an accessory hydraulic pump, often one that was driven off the front of the crankshaft and had its own oil reservoir in one of the loader uprights. Look around at some older compacts and you'll see what I mean.

 

[ptsg]

I second 100% what said.

On the B7000 I had, I used a 0.366 ci pump, if I recall correctly.

The stock pump is like 0.122 ci or something close to that. I once had one of this pumps apart to figure out the displacement. It would work on a loader but as said, just way too slow.

If you still end up going that route, make sure you get a valve for the loader with power beyond capability and the proper power beyond sleeve for that valve.

With the valve figure out, you can then take the hardline from the pump to the 3 pump. Either cut in half or just replace everything with hoses, but you run a hose from the pump to the In port of the loader valve, then a hose from the Power Beyond port to the 3 pt hitch. Then figure a way to run the Tank line of the loader valve back to the transmission sump.

 

[Leejohn]

I posted your parts manuals for the 4 wheel drive and the 2 wheel drive. Don't know what you have so just done both.
It looks like you well have to cut the pressure line and jump up to the loader valve in port.
The loader valve well need a PB fitting, then that line well go the line you just cut. The return line from the loader valve well have to dump into the rear end. You well have to see if you can find a way to do that.

 

[LazyGator]

Thank you for all the help, If I were to mount a external pump lets say to the front crankshaft, the engine spinning is counter clockwise if I remember correct, does the rotation the pump is spinning matter? or is it directional?

 

[LazyGator]

In addition I'm not 100% confident in my abilities to splice and dice the lines, knowing me I'd probably manage to do it backwards

 

[LazyGator]

I second 100% what said.

On the B7000 I had, I used a 0.366 ci pump, if I recall correctly.

The stock pump is like 0.122 ci or something close to that. I once had one of this pumps apart to figure out the displacement. It would work on a loader but as said, just way too slow.

If you still end up going that route, make sure you get a valve for the loader with power beyond capability and the proper power beyond sleeve for that valve.

With the valve figure out, you can then take the hardline from the pump to the 3 pump. Either cut in half or just replace everything with hoses, but you run a hose from the pump to the In port of the loader valve, then a hose from the Power Beyond port to the 3 pt hitch. Then figure a way to run the Tank line of the loader valve back to the transmission sump.

Okay so I just had a thought, If I did this with the lines and got rid of the hard line that is there, ran the new line from the pump where it already connects run it with some kind of diverter valve so if I want the loader I can just turn the valve to allow flow up to the loader controls, then if I need 3ph I turn it the opposite way to allow flow the normal route, for the return I could find the proper thread size, and take out the oil fill into the transmission have it flow straight back into there?

 

[LazyGator]

This is the idea I sketched up with my understanding it should work, any suggestions? I feel like I am on the right route

 

[LazyGator]

I know I am asking a lot of questions but I thought of another... if I have pressure into a spool control valve that has a power beyond setup can I run the beyond part into my 3 point, and not run a return line since the 3 point has one?

 

[Leejohn]

No.. Best to forget the diverter valve, less work and money. There are fitting that you can cut the hard line and hook in real easy. There is a good changes you could dead head the pump with a diverter valve.

 

[ptsg]

Yes, let's forget the diverter valve. All it takes is actuating the diverter valve, creating a pressure spike with no where to go and there goes a cracked pump.

And yes, you do need to connect the Tank line of the loader valve to the transmission sump, no matter what route you use. Unless you use a separate pump with a separate tank, then the line connects to that tank.

 

[LazyGator]

I was looking around and under the seat there is a plug I知 not sure how to describe it, If I tie into that then that could be the source of my high pressure? I saved the photo somewhere I will attach it. They have the stock diverter valve however I do not I will also attach a picture of mine

 

[LazyGator]

So the first one is what I would like to do, the second one is my tractor. I have a plug in the end of the not sure what you call it port I suppose, I cracked it open and it started dripping out with fluid, the return will be as straight forward as the design shown that should function just fine as my return line... I'm not sure if that piece coming from under my seat is pressurized I would assume it is but I could be wrong. Id rather forget the diverter valve as to not risk wrecking my pump. If that piece coming from under the seat is pressurized then my 3 point should still be able to work while the loader is in operation?

My next question I believe PTSG said the pump on the b7000 was 0.122CI what does this mean exactly? when I am looking to get the cylinders and a spool valve what should I be looking for?

 

[Leejohn]

1st off where you get that 1st picture? If on TBN give him a PM. By the looks of it he has to unplug the QC to made the point work, but you can't see all of it. BTY it looks as if his plug is still in. One thing you should find out is if the trans and rear end share the same tank. Some older models might not. It also looks like he isn't using the PB port from the loader, just the return port.

If you do end up cutting the pressure hard line go here https://www.discounthydraulichose.com/ and look at 27405 or 27455.

 

[LazyGator]

I found that picture on another forum I believe he was having troubles with a front snowplow or something, the Trans and rear end do share the same tank, the sump is located I believe just behind the fill plug. I cracked open the plug that's under my seat and it has pressure I'm not 100% sure what the original purpose was for, I was looking at 1" bore Cylinders I think that they should run smoothly? the tractor should be able to handle that size cylinder I would think.

This is the Cylinder https://www.princessauto.com/en/1-i...-cylinders/product/PA1000000428?skuId=8557662

 

[LazyGator]

So I decided I am going to do a pump mounted on the front off my crankshaft, I was able to make a deal to buy a used working pump. The pump is a Ronzio, the pressure bar is 210 which equals 3000 psi I believe, that should be plenty enough for me and I can run whatever cylinder size, I think I will probably end up with a 2 inch cylinder. I believe it is a Ronzio Z1 says made in italy on it thats about it

 

[Dave M7040]

I know I am asking a lot of questions but I thought of another... if I have pressure into a spool control valve that has a power beyond setup can I run the beyond part into my 3 point, and not run a return line since the 3 point has one?

Your sketch does not show a relief valve before the diverter valve so it is possible you could dead head your pump destroying it.

Your 3 pt hitch is a single acting cylinder so only one line is used. Gravity returns oil to the reservoir to lower the 3 pt hitch.

Start at the outlet of your main hydraulic pump and trace the rigid line as it goes towards the rear of your tractor. Look for any location where the rigid line enters and leaves a rectangular piece of metal.

If you find this take pictures and post them.

If you have that hydraulic block life will be much simpler

Dave M7040

 

[Dave M7040]

So I decided I am going to do a pump mounted on the front off my crankshaft, I was able to make a deal to buy a used working pump. The pump is a Ronzio, the pressure bar is 210 which equals 3000 psi I believe, that should be plenty enough for me and I can run whatever cylinder size, I think I will probably end up with a 2 inch cylinder. I believe it is a Ronzio Z1 says made in italy on it thats about it

Make certain the pump will rotate in the proper direction.

Coupling to the front of your engine can be a challenge. It there is a splined stub on the end of the crankshft, finding a fitting wi mate your pump to this splined stub is the big deal

Dave M7040

 

[LazyGator]

I ended up picking up a bi rotational pump as it was more local, 6.7 gpm around 2000 psi I believe. I知 not really sure how I will couple the 2 I might have to make up an adapter of some kind to fit if I can稚 find something I believe it痴 1/2 shaft on the pump