Useing Backhoe hydro ports to run other stuff than just the backhoe

[natem]

I posted this question earlier with no replies, hopefully someone can answer weather this is going to cause harm to the tractor or not. I want to buy a wood chipper with hydro feed. I dont want to spend the money to have rear remotes installed if they are not needed. Is it ok to plug this into the backhoe ports?? I did this with a log splitter and has worked great. When I had told the dealer that this was the plan to run the hydro's on the chipper they suggested to have rear remotes installed, said something about by running it through backhoe ports there is no relief valve. Didnt know if it was just a way to sell me the remotes. You can adjusted the speed of the rollers for the auto feed on a controller on the chipper. Was wondering when i turn the flow down if it is going to cause the hydro pump to over heat because the flow is being restricted, and cause it harm. But on the other hand i am not sure this would be different if it was to run through a set of rear remotes. Pretty simple but yet complicated to explain. The tractor is a kubota L45. Any help would be great!!!

 

[pat32rf]

Your splitter probably has an "open center" control valve- the fluid passes thru with no restriction. When you pull the handle, it diverts to the cylinder. This is the way my JD works. If the hoe hoses are not either hooked up to the hoe, or coupled together, the fluid has no place to go and is pumping against a dead head with no flow----not good.
Sounds like the chipper either has its own motor or is run off the PTO, with the hydraulics only used for feed speed?
What flow do you need for the feed rollers and how much flow would you get from your rear remote (if you tied the handle back)

 

[JohninCT]

Not familiar with what you are calling backhoe ports. Are these not just aux hydraulic outlets? Do they have quick couplers? Are they controlled with a valve? What is the recommended procedure for them when the backhoe is disconnected? It's hard to imagine they would not be protected by a relief since it is usually not hard to to "stall" or overload a small backhoe when working it and attempting something too big (like a stump/root/rock). The fluid pressure has to go somewhere?

 

[tessiers]

I am not familiar with the Kubota but on my JD the backhoe ports are actually a power beyond, meaning they have no valve, just constant single direction flow. Rear remotes will have a valve and usually flow in either direction by way of the valve. If you are connecting something onto the backhoe ports it will need an open center valve, which allows excess flow through. It should be protected by a relief valve in any case but they are not designed to release constantly in a open center system. That would be a closed center system and is a different animal all together. I use my power beyond into a 2 spool valve to give me 2 sets of rear remotes.

 

[tractchores]

Not sure if itll work, but if its like my kubota the bh loop powers the 3pt lift when the bh is off. That means you would have to play with hydro hoses after getting into position each time.

 

[Furu]

Not familiar with either your tractor or your chipper but I have a Deere and a big Salsco chipper with hydraulic feed. I plug my chipper directly into my power beyond 1/2 in QD. The three point still works because I do not bypass it. There is a PB loop circuit and a PB return to tank on the tractor. With the BH you use the PB out flow and return to tank but with the splitter , chipper and other items needing the three point you just plug them into the PB loop. The valves and motors on the chipper all bypass any extra fluid so there is never a restriction to flow. Some of the smaller Deere tractors appear to be plumbed differently so yours might not be able to do the same as mine. My dealer is the one who set mine up and said to use it the way I do. Orange and green are definitely not the same but would bet in this case they are. Look how it is plumbed.

 

[tlbuser]

For stuff that has it's own on/off, stop/ go levers and/ or switches yes you can run off of the backhoe loop. Each piece of equipment attached this way should have it's own pressure relief valve. These can be added inline for not a bunch of money.

 

[dfkrug]

When I had told the dealer that this was the plan to run the hydro's on the chipper they suggested to have rear remotes installed, said something about by running it through backhoe ports there is no relief valve. Didnt know if it was just a way to sell me the remotes. You can adjusted the speed of the rollers for the auto feed on a controller on the chipper.

Your L45 uses a diverter for the backhoe hydraulics, if it is like my B21 TLB.
That lever will bypass the 3-pt cylinder and send flow to the hose
used to power the hoe. Your tractor has a relief valve for the FEL, so
the system is still protected. Check your service manual to see the hyd
circuit diagram.

This means you can use the hoe loop for your chipper hydraulics, but check
to see what pressure the hyd motor on the chipper is rated for, or if it has its
own relief. If it has no RV, but is rated for at least your tractor's RV (2800?),
you will be OK. I suspect it has its own RV cuz the maker does not know
what tractors it will be run on.

Note you can not lift your 3-pt if you do it thru the hoe connection without
switching the diverter lever back. But that should not be too inconvenient.

 

[Farmerford]

I agree with everything DFKrug said and add one caution. I think the hydraulic system on the L45 is 25gpm at PTO speed. The flow control valve on the feed motor may not be rated for a system with that much flow. If it is only rated for say 12gpm the fluid will be heated significantly as it flows through the valve. It will not hurt anything unless the fluid overheats.

Even if you have a 25gpm rated flow control valve, you will get significant fluid heating from the natural action of the valve; it forces the required amount (say 4gpm) through the feed drive motor by restricting the flow of the excess 21gpm. And that restriction heats the fluid. If the drive motor is requiring say 500psi to maintain speed, then the other 21gpm is also experiencing a 500psi pressure drop as it goes through the control valve.

I would certainly try it, but I would either have a temperature gauge in the hydraulic circuit or a hand held thermometer to occasionally check the temperature of the "Excess" port of the flow control valve. Temperatures above 160-180deg F will shorten the life of the fluid due to increased oxidation and the viscosity of the fluid might drop below the requirements of the motor.

 

[dfkrug]

I think the hydraulic system on the L45 is 25gpm at PTO speed.

Excellent point, FF. I forgot that the L39/45 uses a dual pump system for
the hoe, with diverter/pump for the power steering. I don't know how
the different pump flows are plumbed at the hoe. My specs for the L39
show a total hyd flow of 23.4GPM, but "11GPM is for the FEL/hoe, 6.2GPM
is for the hoe swing, and 6.2GPM is for the PS". Gotta have that
hyd schematic! I admit I have not owned or worked on a L39/45.

Also, you pretty much want to be at PTO engine speed cuz that will be
necessary to run the chipper flywheel at the proper speed. You can't
just slow down the engine to reduce the hyd flow in your application.