B670 Backhoe for B7100

[JRHill]

One of these days my 8hp Tecumseh log splitter is gonna have that engine put to sleep with a .308. I relish the day. So before I have that party I am researching the pump on the backhoe as in some quick disconnects to run off the PTO backhoe pump to power the splitter. I would have the pressure and return right off that pump with quick disconnects, using the hyd tank on the splitter.

But before I go any further I need to know the pressure and GPM for the pump on the Kubota B670. It's physically the same size as the pump on the splitter but the splitter has a two stage pump. I don't think I should just swap them. I think the splitter's pump could generate too much pressure for the hoe. OTOH, I don't know if the B670 pump has the umph, so to speak. The splitter's pump can not be spec'd - all I know is they 'look' identical. Of course the splitter's pump runs straight off the engine at governed speed, say 3600 rpm, if and when it actually runs. The PTO pump for the backhoe is of course much slower RPM but I could run it in the 3rd range.

Has anyone done anything like this?

 

[North Idaho Wolfman]

One of these days my 8hp Tecumseh log splitter is gonna have that engine put to sleep with a .308. I relish the day. So before I have that party I am researching the pump on the backhoe as in some quick disconnects to run off the PTO backhoe pump to power the splitter. I would have the pressure and return right off that pump with quick disconnects, using the hyd tank on the splitter.

But before I go any further I need to know the pressure and GPM for the pump on the Kubota B670. It's physically the same size as the pump on the splitter but the splitter has a two stage pump. I don't think I should just swap them. I think the splitter's pump could generate too much pressure for the hoe. OTOH, I don't know if the B670 pump has the umph, so to speak. The splitter's pump can not be spec'd - all I know is they 'look' identical. Of course the splitter's pump runs straight off the engine at governed speed, say 3600 rpm, if and when it actually runs. The PTO pump for the backhoe is of course much slower RPM but I could run it in the 3rd range.

Has anyone done anything like this?

#1 You can not do that, it's an open system.
#2 It's going to be slower than snot!

 

[TheOldHokie]

One of these days my 8hp Tecumseh log splitter is gonna have that engine put to sleep with a .308. I relish the day. So before I have that party I am researching the pump on the backhoe as in some quick disconnects to run off the PTO backhoe pump to power the splitter. I would have the pressure and return right off that pump with quick disconnects, using the hyd tank on the splitter.

But before I go any further I need to know the pressure and GPM for the pump on the Kubota B670. It's physically the same size as the pump on the splitter but the splitter has a two stage pump. I don't think I should just swap them. I think the splitter's pump could generate too much pressure for the hoe. OTOH, I don't know if the B670 pump has the umph, so to speak. The splitter's pump can not be spec'd - all I know is they 'look' identical. Of course the splitter's pump runs straight off the engine at governed speed, say 3600 rpm, if and when it actually runs. The PTO pump for the backhoe is of course much slower RPM but I could run it in the 3rd range.

Has anyone done anything like this?

l

1. Your hoe and splitter are protected by inlet reliefs in the control valves so no such thing as "too much pressure".
2. Tbe two stage pump makes higher flow at lower (~800) PSI and flow drops way back to develop full pressure. Not what you want for a hoe.
3. The PTO pump runs slower but has a much larger displscement to make up for that. It produces full flow and pressure at all times.
4. Speed of the splitter is going to depend on cylinder stroke and bore and displacement of the PTO pump. See if you can find a number on it.

Dan

 

[JRHill]

Neither pump on the backhoe or the splitter have any markings or tags.

 

[TheOldHokie]

Neither pump on the backhoe or the splitter have any markings or tags.

 

[TheOldHokie]

1. Remove return line from backhoe reservoir and stick it in an empty 5 gallon bucket..
2. Disengage PTO, start tractor, and set enginel speed to 540 PTO speed
3. Engege PTO and time how long it takes to fill bucket to 4 gallon marrk

You now kmow flow rate @540 pump RPM.

Dan

 

[GreensvilleJay]

$249 gets you a replacement engine for the splitter from HF. With just a little TLC ( drain carb, run engine dry ) ,it'lll probably outlive you.

 

[JRHill]

$249 gets you a replacement engine for the splitter from HF. With just a little TLC ( drain carb, run engine dry ) ,it'lll probably outlive you.

Yup, there is that option. And probably the wisest one.

 

[Swede1962]

Yup, there is that option. And probably the wisest one.

I purchased one of the HF engines for a defunct Snapper rear-tine tiller. Bolted right up and performs very well. The only take away is the throttle control is not on the operator handle any longer. I've adjusted to that minor inconvience. I close the fuel valve each time I shut it down for any extended period of storage. Upon opening the fuel valve for starting it's only 2 or 3 pulls and the things runs like a champ. Been 3 seasons and still running strong.

 

[GreensvilleJay]

you can connect the 'operator throttle cable' to the engine ! just remember to loosen the 'tension' nut a bit.

 

[Swede1962]

you can connect the 'operator throttle cable' to the engine ! just remember to loosen the 'tension' nut a bit.

Not in this case. It would have required a new throttle cable and some re-engineering. Not needed in my opinion. Been tilling 3 seasons now and doing just fine. Thanks!