Convert BL4690 backhoe to 3rd function?

[pMan6000]

Hey all,

I'm planning on picking up an L3600 that comes with a 4690 backhoe. It runs off its own PTO pump and hydraulic fluid reservoir, I understand the benefits of that but I can't help but wonder if the in & out lines could have quick connects swapped onto them and then be hooked up to the tractors rear 3rd function? Would I run into any flow issues with this and would I need to keep the reservoir on the backhoe in the loop?

 

[GreensvilleJay]

Only spec I can find quickly ,is that it needs 7GPM MINIMUM......
Have no idea if your L3600 can supply that..

 

[pMan6000]

Only spec I can find quickly ,is that it needs 7GPM MINIMUM......
Have no idea if your L3600 can supply that..

Gotcha well that’s half of it, maybe in the FSM I can find the flow rate for the 3rd function. Do you have any ideas on other ways to measure it/find out?

 

[TheOldHokie]

Hey all,

I'm planning on picking up an L3600 that comes with a 4690 backhoe. It runs off its own PTO pump and hydraulic fluid reservoir, I understand the benefits of that but I can't help but wonder if the in & out lines could have quick connects swapped onto them and then be hooked up to the tractors rear 3rd function? Would I run into any flow issues with this and would I need to keep the reservoir on the backhoe in the loop?

You want to ditch the PTO pump and run it off the tractor remote hydraulics?

Dan

 

[pMan6000]

You want to ditch the PTO pump and run it off the tractor remote hydraulics?

Dan

Yup correct, if it's worthwhile of course.

 

[TheOldHokie]

Yup correct, if it's worthwhile of course.

Your tractor hydraulic system produces a little under 8 GPM. Whether or not that is sufficient for the backhoe is hard to say but is easy enough to try it and see. The loader connects to the hydraulic outlet block on the side of the tractor. Disconnect the loader return quick connects shown in the diagram below and use them to feed the backhoe. No need to use any of the pump or reservoir plumbing on the backhoe. If the result is not satisfactory simply reconnect the loader and PTO pump.

Dan

 

[pMan6000]

Your tractor hydraulic system produces a little under 8 GPM. Whether or not that is sufficient for the backhoe is hard to say but is easy enough to try it and see. The loader connects to the hydraulic outlet block on the side of the tractor. Disconnect the loader return quick connects shown in the diagram below and use them to feed the backhoe. No need to use any of the pump or reservoir plumbing on the backhoe. If the result is not satisfactory simply reconnect the loader and PTO pump.

Dan

View attachment 85330

Gotcha, thanks for the schematic Dan. If the system is running around 8 GPM and if what GreensvilleJay says is true, then it should at least do something. I would be hooking it up to the 3rd function at the rear of the tractor next to the small storage compartment behind the seat, I assume it was either a factory option or added on. Either way there is an unlabeled lever next to the PTO engage/disengage lever that I believe is the flow control for that 3rd function. I wouldn't have to mess with the loader hydraulics that way and the cable run would be short and simple.

 

[TheOldHokie]

Gotcha, thanks for the schematic Dan. If the system is running around 8 GPM and if what GreensvilleJay says is true, then it should at least do something. I would be hooking it up to the 3rd function at the rear of the tractor next to the small storage compartment behind the seat, I assume it was either a factory option or added on. Either way there is an unlabeled lever next to the PTO engage/disengage lever that I believe is the flow control for that 3rd function. I wouldn't have to mess with the loader hydraulics that way and the cable run would be short and simple.

According to the backhoe manual the displacement of the PTO pump.is 2.05 cubic inches. At PTO speed of 540 RPM that works out to 4.8 GPM which is considerably less than the tractor produces. Flow rate should not be a problem.

Dan

 

[pMan6000]

Here's a photo of the PTO pump and lines if it helps at all. I figure I could use the pump for a 3-point mounted log splitter or something like that in the future, if it flows enough for the backhoe I'd think it would flow enough for a splitter.

 

[pMan6000]

According to the backhoe manual the displacement of the PTO pump.is 2.05 cubic inches. At PTO speed of 540 RPM that works out to 4.8 GPM which is considerably less than the tractor produces. Flow rate should not be a problem.

Dan

That sounds perfect Dan, thank you for digging up that info. I guess I'll swap some quick connects on and give it a try when I pick up the tractor.

 

[TheOldHokie]

Here's a photo of the PTO pump and lines if it helps at all. I figure I could use the pump for a 3-point mounted log splitter or something like that in the future, if it flows enough for the backhoe I'd think it would flow enough for a splitter. View attachment 85332

I would use the same tractor hookup for the log splitter.

Dan

 

[pMan6000]

I would use the same tractor hookup for the log splitter.

Dan

Fair enough, it obviously will be putting out more flow so I could split larger rounds. I guess the pump can kick around till something comes up.

 

[TheOldHokie]

Fair enough, it obviously will be putting out more flow so I could split larger rounds. I guess the pump can kick around till something comes up.

Pressure dictates splitting force. Flow rate dictates cycle speed on the cylinder. If you are going to run a splitter on a 8 GPM tractor I would reccomend you get one with a fast extend valve. I just swapped the valve on my splitter for one with fast extend and its well worth the couple hundred bucks.

Dan

 

[pMan6000]

Pressure dictates splitting force. Flow rate dictates cycle speed on the cylinder. If you are going to run a splitter on a 8 GPM tractor I would reccomend you get one with a fast extend valve. I just swapped the valve on my splitter for one with fast extend and its well worth the couple hundred bucks.

Dan

Something like this?

 

[TheOldHokie]

Something like this?

No like this.

Prince Hydraulic Log Splitter Valve Rapid Extend 25gpm Part Lsr-3060-3 for sale online | eBay

Find many great new & used options and get the best deals for Prince Hydraulic Log Splitter Valve Rapid Extend 25gpm Part Lsr-3060-3 at the best online prices at eBay! Free shipping for many products!

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It has two positions for the extend stroke.

• First position is regenerative for high speed extension but with reduced force. You use this position to start the split. When the wedge hits resistance it may stall because the force is reduced.
• If the wedge stalls you simply move the handle to the next position where ram travel speed is reduced but you get full splitting force.

It is easy to use and really does speed up splitting operations.

Dan

 

[pMan6000]

Ahh that is clever. Any suggestions for hydraulic cylinders?

 

[TheOldHokie]

Ahh that is clever. Any suggestions for hydraulic cylinders?

Cylinders for what?

Dan

 

[pMan6000]

Cylinders for what?

Dan

Sorry, good cylinders for the splitter ram. I found some around the right size on google but they all seem to be pretty cheap.

 

[TheOldHokie]

Sorry, good cylinders for the splitter ram. I found some around the right size on google but they all seem to be pretty cheap.

I assumed you had or were going to buy a splitter. Hard to make one for less than off the shelf units cost.

Dan

 

[Hkb82]

I’ve also been looking for a used 3ph and just curious why you wouldn’t just run it if the pto pump? More flow I’m guessing but any other advantages? I’ve seen both well looking and never really thought about converting a pto pump one to my tractor hydraulics.