Torch, excellent mill work. I have a question. Your description of needing to use the Power Beyond fitting confuses me. In attached image, I came out of the hydraulic block to the inlet of a Prince open-center valve, & back to the block from the return port of the valve & both my three-point & front blade work. Why is the Power Beyond hose needed?
B7100-HST hydraulic confusion
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torch
Well-known member
Equipment
B7100HSD, B2789, B2550, B4672, 48" cultivator, homemade FEL and Cab
Ok, right now you have effectively piped the Tank line to the 3ph control valve instead of the Tank. When your Prince valve is in neutral, fluid simply flows through the open centre and on to the 3ph, just as if it was piped via a PB port.
However, when you operate your Prince valve and the cylinder reaches the end of its travel causing the relief valve to operate, the excess fluid goes to the 3ph control instead of the Tank. Let us say for the sake of argument that the Prince relief valve is set to 2,000 psi.
The 3ph spool valve is also open centre, so when it is in the neutral position the fluid flows into the tank and pressure on your hydraulic pump, Prince valve and cylinders is limited to a safe 2,000psi.
However, when the 3ph spool valve is operated, that open center is closed off. The only path to the tank is now through the 3ph relief valve. Let us say that is set to 1,700 psi.
So if both valves are operated at the same time, the relief valves are in series and therefore the pressure on the hydraulic pump, Prince control valve, cylinders and all connecting lines could hit 2,000psi + 1,700psi = 3,400 psi!
At that pressure, it is very likely something will break. Hopefully something cheap like a hydraulic line and not something expensive like the hydraulic pump drive tang on the fuel injection camshaft.
So yes, you might get away with just 2 hoses and no PB adapter. But do you really want to chance it?
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Very well done, thanks. I will be attempting to make this, this week. Great job on detail and explanation.I don't know if you are aware of this, but to use the hydraulic block as I have described, you need to swap out the top to redirect the flow. The original looks like this:
You can make your own by drilling and tapping a suitable block of steel or even possibly aluminium, like so:
Here are the details:
I am new here but just do a lot of reading mostly. I have a 1977 Kubota B6000 that I just got a loader for and I built a twin snow blower to go on the front. I can’t post pics yet because I am new.
Block are still available?I don't know if you are aware of this, but to use the hydraulic block as I have described, you need to swap out the top to redirect the flow. The original looks like this:
You can make your own by drilling and tapping a suitable block of steel or even possibly aluminium, like so:
Here are the details:
(EDIT: for those led here by Google, see also https://www.orangetractortalks.com/...ock-diverter-70060-00360-or-70070-00385.56471 to get one.)
The diverter valve (PN# 70070-00385) has been discontinued for a while. If you can't find one through salvage, you can have one milled like the OP.
torch
Well-known member
Equipment
B7100HSD, B2789, B2550, B4672, 48" cultivator, homemade FEL and Cab
I'm working on another batch. Have them cut and milled to size, just boring and tapping the holes yet to be done.
North Idaho Wolfman
Moderator
Staff member
Lifetime Member
Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Good morning I am new on this site. I own a small lathe and milling, I was looking at your block drawing it is well made, I was looking at your drawing, if I follow right, the tapping will be on both side of the block, the drawing was from the face only . You would be very nice to help me. i could also buy a block from you
First Kubota a old one but i a good shape ( project front end loader on a B 7001) i wish you a good day
torch
Well-known member
Equipment
B7100HSD, B2789, B2550, B4672, 48" cultivator, homemade FEL and Cab
No need to buy one from me if you are set up to make your own! I am just a hobbyist and provide these at my cost to those in the community that don't have the capability of making their own. It's not a business and I don't lose any money by sharing my "secrets" with anyone else. Not that they are really MY secrets anyway -- Kubota made the basic dimensions publicly available and it was this community that figured out how to make a "universal" version.
Here is a picture of the "universal" design we came up with to fit multiple models. This angle shows the outer face, with tapped outlets. So there are a total of 6 tapped outlets in the "universal" version -- but you only need and can only use 2 of them. The other 4 have to be plugged. So If you are making your own for your specific tractor you only have to drill and tap 2 of them.
The OEM version for the B7100 just had the large face drilled and tapped -- none on the edge or the ends. When I made mine for my own B7100, I found the best hose routing for me was one on the face and one on an end.
The picture below shows the opposite face -- the face that mates with the tractor's block. Note that the holes on this side are NOT tapped, and the face is polished smooth and flat on a surface plate to remove any milling marks that might eventually cause damage to o-rings or leakage.
Mine are tapped 3/8" NPT. My blocks are 30mm thick 6061 - T6 aluminium. (The first ones I made were steel, but aluminium is easier to machine, lighter and cheaper to ship, doesn't rust and works just as well). The holes on the edge and end are not centred -- they are offset towards the mating surface by 2-1/2mm (if I recall correctly -- I'm at work and don't have the measurement here with me). The offset is to ensure the intersecting holes leave sufficient meat on the threaded side to ensure strength and integrity.
I ship mine with new o-rings and pipe plugs for convenience of the end user. The o-rings are 7/8" ID x 1" OD, IIRC. Butyl will work for this application. Viton or nitrile (Buna-N) are even better. The recesses for the o-rings are already machined into the tractor's block. All you need to make is a smooth surface.
One last picture, showing all sides in one image:
