Need a little help on Hydraulics for a 3 Point Log Splitter

[Kzooandy]

BX 25D Need a little help on Hydraulics for a 3 Point Log Splitter

As one other poster has done, I picked up an older Bush-Hog brand Log Splitter 3 Point mounted.

I want to just try running it with the BX25D on board pump and hydraulic ports, but confusion crept in and I'm hoping to get some input and help.

I have doctored some pictures and taken a shot from my manual.

First question What is Power Beyond? Or what does that refer to.
I have two lines on the splitter to couple to the tractor. An inlet and an outlet. HOWEVER... the tractor has an outlet hose, that loops to the Power Beyond Port on the tractor. And the Return pipe has a cap.

I would guess that the splitter return line, would go into the return pipe (white capped on tractor)

The mystery is trying to understand what the hydraulic fluid is doing when the backhoe is removed and that looped line is there.
If I hook up my inlet to the splitter to the (4) Outlet Hose Tractor (looped when backhoe removed) what do I do with the "power beyond" port that appears to be a return.

ALSO... If I combined the Power Beyond and the "tractor Outlet... would one get higher GPM. The tractor pump is rated at 6.2 GPM, but the Tractor Outlet hose (per the picture below) is only 3.7 GPM. I'm guessing the Power Beyond is also just an additional pump outlet? Would they be common or equal pressure from the pump? Would they combine to make close to the 6.2GPM. That's nearly double the output that could go to the splitter ram.
It's all a bit confusing so take a look at the pictures and tell me what you think.
Thanks for the help.

 

[Tractor Seabee]

I also have a BX 25. The Operating manual does not provide much info on what you are seeking. I have studied the hydraulic system in the Workshop Manual. I always recommend on these posts that if you are doing any mechanical service or work yourself then the WSM is a must have. You can order through your dealer, any other source is violating Kubota's copyright.

As far as I know the GPM is the same throughout the system, that is what the PB circuit does. The PB circuit is a continuation of the power (P) output of the pump. I goes from P to PB to P as it continues through the BH, FEL and then the 3PT control valves. You cannot connect it any other way. Each valve cluster has a return to the hydraulic sump/tank the T connection.

You can connect the splitter to the P and T connections leaving the PB hose hanging plugged. You need the splitter set where you want it as once connected w/o continuing the PB the FEL and 3 Pt will not function. You will get the full GPM to the splitter.

With that used splitter you need to purge the hoses, valve assembly, and cylinder with new SUDT2 fluid as you do not want to mix UKN fluid and maybe dirt into the tractor system. You need a QC fitting to put in the T hose to do this. Purge each posistion of the valve till you get clean new fluid flowing from each side. Dispose the purged fluid same as crankase oil. You may need up to a gallon or more depending on cylinder size.

If you are mechanically inclined you should understand this dialog and fill in the blanks as it is not as detailed as if I was standing over your shoulder. If not you will probably be dependent on your dealer's shop/friend/neighbor to help you. LOL

Ron

 

[Kzooandy]

Ron,
I don't want to belabor this, and thanks for the detailed response.
Sounds like the WSM is a good investment. I do all my own service work, (for the most part). Always feel violated when dealing with service departments. It shouldn't be that way, but I think thats an age old argument.
Do you know the Kubota part number for the Workshop Manual for the BX 25?

Ok, the outlet hose from the left side is (P) and disconnects from the right side (PB Steel pipe hard fixed to tractor)...so If I understand your description of the Hydraulic system, the P and the PB are the same potential. So...by combining them with a brass "T" (or equivalent) will not gain me anything in GPM?
Will combining them essentiall keeping the loop (when BH disconnected) keep fluid going to my 3PH arms and FEL, so I can pick up the splitter. Seems like a PITA to have to unhook the splitter hoses, and reconnect the jumper hose...P to the PB port to have hydraulic lift. Win Some Lose Some type problem? Very curious if there is a way to connect to keep all things working.

Completely understand the fluid issue, and will order some Super UDT2... Best I'm seeing it at is $`$28 a gallon (Messicks) to the door in a 5 gallon, I'll call the dealer too, but they are quite a ways away, so gas money time etc comes into play. Lowest price I saw on 1 gallons was $28 and $9 shipping.

I glaze over when it comes to Hydraulic couplers too, You mentioned a QC fitting to put in the T Hose (fixed port on tractor?). Is the QC what's on the Kubota BX 25 stock? I can work through this, as I have a hydraulic hose supplier nearby that I can get all of it figured out, but knowing some of the numbers helps. On the splitter, one hose is open right now, and one has a Pioneer fitting on it, which will come off, so I can purchase any correct fitting to complete the connection.

 

[J_J]

Perhaps I can help.

Your hyd system is an open center hyd system, and the log splitter should have a open center valve on it to work correctly.

If your valve has two lines, the PB out of the tractor should be connected to the IN port on the log splitter valve.

The log splitter return line should go to tank/return line. Like your capped return line

All PB pressure lines can handle the pressure developed by the pump and hyd components, and connect from valve to valve in a series configuration.

The loop is the PB feeding the 3pt.

The return pipe with a cap, is for a return flow like from a log splitter or a BH.

If your log splitter has three hoses or outlets, the log splitter PB line would go to the 3pt in port, and provide all functions including 3pt.

Option 1,

and I don't recommend this, but if the log splitter valve has two hoses, the return could go to the port for the 3pt and provide a complete path..

The only problem with this is that the log splitter OUT port is not designed for high pressure, and by routing the flow through the series hyd circuit, the log splitter OUT port could see up to 2500 psi. If you simply want to position the log splitter, you can probably get away with the configuration.

When you remove the log splitter, re-connect the loop hose.

You say that you only have 3.7 GPM pump flow.

You would benefit using this valve made by Prince. LSR-3060

TYPICAL PERFORMANCE with a 3 GPM pump, and a 4" bore cylinder with a 2" rod:

Rapid-Extend speed: 3.7" per sec. (24" in 6.5 sec!) Full bore speed: .92" per sec.
Rapid-Extend force: 7,850 lbs @2,500 PSI Full bore force: 31,400 lbs
Retract speed: 1.22" per

http://www.princehyd.com/Products/Hydraulic-Valves/Mono-Block/Rapid-Extend-Log-Splitter

http://www.ebay.com/itm/PRINCE-HYDR...ID-EXTEND-25GPM-PART-LSR-3060-3-/261333596332

 

[The Fred]

Perhaps I can help.

Your hyd system is an open center hyd system, and the log splitter should have a open center valve on it to work correctly.

If your valve has two lines, the PB out of the tractor should be connected to the IN port on the log splitter valve.

The log splitter return line should go to tank/return line. Like your capped return line

All PB pressure lines can handle the pressure developed by the pump and hyd components, and connect from valve to valve in a series configuration.

The loop is the PB feeding the 3pt.

The return pipe with a cap, is for a return flow like from a log splitter or a BH.

If your log splitter has three hoses or outlets, the log splitter PB line would go to the 3pt in port, and provide all functions including 3pt.

Option 1,

and I don't recommend this, but if the log splitter valve has two hoses, the return could go to the port for the 3pt and provide a complete path..

The only problem with this is that the log splitter OUT port is not designed for high pressure, and by routing the flow through the series hyd circuit, the log splitter OUT port could see up to 2500 psi. If you simply want to position the log splitter, you can probably get away with the configuration.

When you remove the log splitter, re-connect the loop hose.

You say that you only have 3.7 GPM pump flow.

You would benefit using this valve made by Prince. LSR-3060

TYPICAL PERFORMANCE with a 3 GPM pump, and a 4" bore cylinder with a 2" rod:

Rapid-Extend speed: 3.7" per sec. (24" in 6.5 sec!) Full bore speed: .92" per sec.
Rapid-Extend force: 7,850 lbs @2,500 PSI Full bore force: 31,400 lbs
Retract speed: 1.22" per

Model LS3060 Rapid Extend Log Splitter

Prince Hydraulic Log Splitter Valve Rapid Extend 25GPM Part LSR 3060 3 | eBay

It's great to have an expert on these forums J.J. You are the man! Thank-You.

Fred

 

[Tractor Seabee]

Ron,

See my responses in red.
Do you know the Kubota part number for the Workshop Manual for the BX 25? No, I just ordered by name, like OEM parts you can only get the WSM through a dealer.

Ok, the outlet hose from the left side is (P) and disconnects from the right side (PB Steel pipe hard fixed to tractor)...so If I understand your description of the Hydraulic system, the P and the PB are the same potential. So...by combining them with a brass "T" (or equivalent) will not gain me anything in GPM? True, Any fittings you use need to be forged steel, 3000 PSI rated, your hydraulic shop will have.
Will combining them essentiall keeping the loop (when BH disconnected) keep fluid going to my 3PH arms and FEL, so I can pick up the splitter. Never thought about that. If you did you would need to also tee the T connection so the Tank/discharge side of the valve is not pressurized to the P pressure. Seems like a PITA to have to unhook the splitter hoses, and reconnect the jumper hose...P to the PB port to have hydraulic lift. Win Some Lose Some type problem? Very curious if there is a way to connect to keep all things working. The splitter valve JJ mentioned will give a power boost but it is not a PB type. I think you are wrong on the GPM. I find nothing in the WSM that indicates the GPM is less than the pump output other than the Power steering which is controlled separately. Prince makes a PB splitter vale but it costs twice as much as the one JJ cited. GPM at the splitter only affects the cycle time not the force. Hope there is someone else out there that has done this setup.

Completely understand the fluid issue, and will order some Super UDT2... Best I'm seeing it at is $`$28 a gallon (Messicks) to the door in a 5 gallon, I'll call the dealer too, but they are quite a ways away, so gas money time etc comes into play. Lowest price I saw on 1 gallons was $28 and $9 shipping. Kubota's price is why I buy NAPA 85-505 in 5 gallon cans. I get 5 gallons for a little more than K's 2 gallons. NAPA gives me their fleet discount. 1000 Hr later and no apparent problems, buy my filters there also. This subject has been discussed plenty in other threads so it does not warrant discussing on this one. (HINT)

I glaze over when it comes to Hydraulic couplers too, You mentioned a QC fitting to put in the T Hose (fixed port on tractor?). Is the QC what's on the Kubota BX 25 stock? I can work through this, as I have a hydraulic hose supplier nearby that I can get all of it figured out, but knowing some of the numbers helps. On the splitter, one hose is open right now, and one has a Pioneer fitting on it, which will come off, so I can purchase any correct fitting to complete the connection. You will need to get matching fittings for you hoses. My BX has standard Parker QCs. The number is embossed on the side of the female fitting. Your hydraulic shop should have or can order. Kubota keeps this a secret from the WSM, I suppose as they sell them for twice as much.

I am working on the same issues as your are but have not finalized my design. I plan to incorporate one detent valve in a rear remote array that will use a PB valve block. That way the PB is covered there and will be in place whenever the BH is off to control a top and tilt arrangement for the 3PT.

Keep us posted.

Ron

 

[Kzooandy]

Thanks.. More questions and replies in Red


Perhaps I can help. ... I Appreciate the help, not trying to be a Pain, just trying to get my head around this. I like to truly understand machines and Hydraulics have eluded me, mostly because I never needed to set anything up like this. Most hydraulic things...are all done, so there is no need for most "users" to understand the flow schematic. So.. please bear with me, and I truly appreciate your knowledge and how you share with the forum.

Your hyd system is an open center hyd system, and the log splitter should have a open center valve on it to work correctly. Yes it has a ENERGY brand DSKCVA-200 with the older hydraulic over mechanical pin (that moves) to kick it back to neutral position) Center Open and 4 ports. In Out and the A and B. It detents in the return position then when the hydraulic ram reaches the end of stroke, the extra pressure pushes a pin to kick to neutral.

If your valve has two lines, the PB out of the tractor should be connected to the IN port on the log splitter valve. Still not sure which port is PB The one with the short whip hose male coupler connected to what looks like a pressure regulator type housing (left)... or the one with the female coupler and is a hard pipe down to a thingy with about 4 or 5 hard pipes that go out to the FEL.

The log splitter return line should go to tank/return line. Like your capped return line I'm good with this one. White capped one = return from log splitter

All PB pressure lines can handle the pressure developed by the pump and hyd components, and connect from valve to valve in a series configuration. I removed the jumper hose and ran the tractor, it straightened out when I idled up the tractor, indicating pressure going up. I reconnected it for now. ALSO... when the hose was disconnected, the 3 point arms lowered, no matter which position I put the controller arm. after re-coupling, arms worked normal. But again, which way is the fluid going?

The loop is the PB feeding the 3pt. Yes it sure is (lol) but I don't understand why the hose straightens out when decoupled, it sure seems like the pressure is pushing out from the left. Sorry guys, I just cant get my head around this. Is the hose on the left, as well as the PB connector on the right both pushing fluid, but when coupled together it runs the 3 point arms. That is really confusing to me. Maybe it doesn't matter. Are they both pump discharges? Both on the high pressure side? Sorry if I sound like an idiot, but I don't want to connect the log splitter supply to the wrong port and screw something up. Hydraulic systems can be a little deceptive, and you cannot assume you know know which way the fluid is going... at least for me.

The return pipe with a cap, is for a return flow like from a log splitter or a BH. This I think we agree on...looks like it goes right back into the main block of the trans casting.

If your log splitter has three hoses or outlets, the log splitter PB line would go to the 3pt in port, and provide all functions including 3pt. No... just two hoses to the tractor, and two to the cylinder, front and rear

Option 1,

and I don't recommend this, but if the log splitter valve has two hoses, the return could go to the port for the 3pt and provide a complete path.. Again... left side or right side (left has male connector and short hose right has hard pipe and female side)

The only problem with this is that the log splitter OUT port is not designed for high pressure, and by routing the flow through the series hyd circuit, the log splitter OUT port could see up to 2500 psi. If you simply want to position the log splitter, you can probably get away with the configuration. Still curious if you use a hydraulic TEE, or Splitter to allow fluid to loop around, AND go to the inlet of the log splitter valve. The Outlet of the log splitter, will be hooked to return port (white cap), so if the splitter is hooked up to the 3point, and the inlet is "TEED" into the loop line, I would think both could work. Thoughts?

When you remove the log splitter, re-connect the loop hose. Makes sense. When the loop hose is off, the 3 point just sags lower and lower, no matter which position the control set-point is at.

You say that you only have 3.7 GPM pump flow. Factory Literature says pump can create 6.2GPM, but assuming the steering takes some all the time...1+GPM. Also, the picture from the manual says 3.7GPM on the "to backhoe outlet) pipe (4) in my pictures. Doesn't matter as long as it's fast enough.

You would benefit using this valve made by Prince. LSR-3060 Ordered it today. So...I'll be replacing my ENERGY brand valve and going to the Prince. This seems like a great upgrade. I was very concerned It would be too slow, but your calculations look very tollerable.

TYPICAL PERFORMANCE with a 3 GPM pump, and a 4" bore cylinder with a 2" rod:

Rapid-Extend speed: 3.7" per sec. (24" in 6.5 sec!) Full bore speed: .92" per sec.
Rapid-Extend force: 7,850 lbs @2,500 PSI Full bore force: 31,400 lbs
Retract speed: 1.22" per

 

[Kzooandy]

I am working on the same issues as your are but have not finalized my design. I plan to incorporate one detent valve in a rear remote array that will use a PB valve block. That way the PB is covered there and will be in place whenever the BH is off to control a top and tilt arrangement for the 3PT.

Keep us posted.

Ron

Thanks for the reply, I asked some additional questions and comment on J-J's reply.
I'll contact my dealer about the WSM

I went ahead and ordered the 5 gallon Kubota oil, knowing I need a gallon or more for the cylinder, plus I just don't want to introduce anything too new to the system, and gives me a change in a couple years or whenever my hours hit. I'm not a service nut job for hours, but don't want to just mix oils and my machine is so new. Thanks for the hint though, I had already ordered from Messicks when I read your reply. No big.

I saw plenty of Parker fittings at the hydraulic place.

 

[J_J]

One can not tee into a series hyd path for this reason. The fluid will go to the path of least resistance.

Where the BH PB line goes to the tractor, that is a high pressure port and feeds the 3pt.

Since your log splitter valve does not have PB, and you don't need the 3pt, use the tank port.

If you need the 3pt with the log splitter, then you have to send the OUT flow from the log splitter to the 3pt in port.

There should not be any pressure on the 3pt hose if not coupled to the PB port on the tractor.

If the PB hose has a QD on it and you start the tractor, you will put the first valve in the hyd system into relief, and the hose will get tight.

If you plugged a hyd gage in that QD, you would read system pressure.

 

[Kzooandy]

View attachment 361540

One can not tee into a series hyd path for this reason. The fluid will go to the path of least resistance.

Where the BH PB line goes to the tractor, that is a high pressure port and feeds the 3pt.

Since your log splitter valve does not have PB, and you don't need the 3pt, use the tank port.

If you need the 3pt with the log splitter, then you have to send the OUT flow from the log splitter to the 3pt in port.

There should not be any pressure on the 3pt hose if not coupled to the PB port on the tractor.

If the PB hose has a QD on it and you start the tractor, you will put the first valve in the hyd system into relief, and the hose will get tight.

If you plugged a hyd gage in that QD, you would read system pressure.

It's beginning to make sense. I think my biggest confusion is the Kubota Owners Manual diagram. After looking again, it says PIPE meaning a metal pipe (item 6) the verbage in the description is still confusing. The "B" hose has an arrow pointing up to the PB PIPE on the tractor, suggesting that the fluid is going into that port (PB).
I'll start getting things cleaned up and my fittings sourced. will probably try it first with the old ENERGY valve and do some timing, then replace the valve if it's horribly slow.

Anyway, thank you very much for the help.