Backhoe Internal hydraulics vs. PTO pump to run backhoe

[kemartin3]

I'm interested in how folks with tractors in the 30-40HP range are providing hydraulics to their backhoes. Mine is a Kubota L3710 which is spec'd at 7.8GPM. The hoe I'm looking at is a Woods BH80-X which is supposed to need 5-7GPM. At first glance it would seem like using the internal hydraulics (tap into the circuit on the side of the 3 pt case where Kubota does to feed their auxiliary valves) would work fine. But the dealers I've talked to hem and haw, and don't really want to commit on an opinion. I'm going to call Woods to get their input, but nothing beats empirical evidence from folks who have actually done it. If you can tell me why you made the decision you did and what model tractor/hoe you have, then I can match up the flow rates for your combinations and see how they compare to mine. I'd sure like to not have to buy that $1000 pump assembly if I don't need to. I'm not doing commercial work, so it doesn't need to be lightening fast.

As always, thanks for all of the good information!

 

[kennyd]

I think you'll be fine without the PTO pump. Your tractors hydraulic system should be able to power that hoe without any trouble at all.

 

[DK35vince]

Your tractor hydraulics would run the 80-X backhoe with no problem.
No need for a PTO pump.
I have a Kioti DK 35, it runs a Rhino 85 (8 1/2' digging depth) backhoe fine without a PTO pump.

 

[DaryleD]

I also think that you should be fine. I have a New Holland TC30 with a New Holland 757 backhoe and it works fine. I just checked the NH website and The TC30's put out 6.1gpm flow, and I think that mine is plenty fast. Save your money from that pump and possibly get a thumb for it. Let us know how you like it.
Daryle.

 

[rbargeron]

...... but nothing beats empirical evidence from folks who have actually done it........

The size (inside diameter) of the hydraulic cylinders makes a big difference in digging force and oil gpm required (speed). 3" cylinders make 50% more force - but also need 50% more gpm to operate at the same apparent speed as 2-1/2" cylinders. Looking at the Woods specs, the BH70, BH80 and BH90 models look like they have 2-1/2", 2-3/4" and 3" cylinders, respectively. Your 7-8 gpm pump would be "normal speed" with BH70, about 20% slower with a BH80 (still not bad) and 50% slower with a BH90 (a little pokey). I agree with the others a pto pump isn't really necessary.

 

[shaley]

What rbargeron said... I have the BH9000 with a 10gpm tractor pump. The tractor pump gpm is based on about a 2000 RPM engine rating. I chose to get the aux pump B/C I didn't want to run my machine at WOT. I think you will be OK with out the aux pump because of the smaller dia. cylinders. You can always add it later.

 

[vallyfarm]

How big is your oli capasity? How much work do you plan to do with the hoe? If you do much digging and have only 5 gal capasity in the tractor, overheating the fluid may be a problem. I went with the pto pump because I can run the travtor at around 1/3 throtle and still dig with full power. $1000 will look pretty cheap if it avoids damage to the tractor. Also, now you can put it on any machine big enough to hold the hoe. Resale value is much better on a hoe with the pto pump. Mike

 

[dfkrug]

The size (inside diameter) of the hydraulic cylinders makes a big difference in digging force and oil gpm required (speed). 3" cylinders make 50% more force - but also need 50% more gpm to operate at the same apparent speed as 2-1/2" cylinders. Looking at the Woods specs, the BH70, BH80 and BH90 models look like they have 2-1/2", 2-3/4" and 3" cylinders, respectively. Your 7-8 gpm pump would be "normal speed" with BH70, about 20% slower with a BH80 (still not bad) and 50% slower with a BH90 (a little pokey). I agree with the others a pto pump isn't really necessary.

I have measured the BH80-X dipper cylinder to be 2.75" OD, which indicates
an ID of about 2.45". Using a stopwatch and a precise measurement of the
volume of the dipper cyl on my Prairie Dog hoe (2.93" OD), I can see that
a 4-5 GPM flow rate is plenty for a decent digging speed. This is a little over
half throttle for my CK30 and my JD955. A hoe with larger cyls (> 3" OD)
would be slower at that rate, of course.

As for overheating the fluid, this is where having an HST tractor with
oil cooler and 8-10 total gal of fluid illustrates one of the overwhelming advantages of using the tractor's hyd system rather than a PTO pump.

 

[Spiveyman]

I had the exact same question for a Ford 6610, so I'm hoping I can just use this thread rather than starting a new one. I just ordered a Bush Hog FEL, my tractor has 2 remotes. I am assuming it will take both remote slots to run the FEL. Not sure if that is correct or not. I am also interested in getting a Backhoe, probably also a Bush Hog BH950, 6-8 GPM. The dealer will get me a PTO pump for about $340 with the back hoe order, so it's not that much more money.

My question, is there any performance difference between tractor hydraulics and a PTO driven system? Anything to beware of? I don't want to have to unhook the FEL hydraulics to use the backhoe if there'a no reason to do so.

Thanks.

 

[rbargeron]

....... I'm not doing commercial work, so it doesn't need to be lightening fast.....

That's the main factor right there - a new operator can get by with 5gpm because they are not familiar with a backhoe yet. But an experienced person digging commercially would want much more speed. You can always start off using the internal pump and put on a pto pump later if you decide you need one.