Larger capacity hydraulic pump

[MChalkley]

Peter - I would be very interested in seeing the pages that describe the HST design, if it's not too much trouble. Does it use a separate external pump and motor, or are they both contained within a transmission case as with the Kubota? If they're separate, do you know who makes them?

As for work, I do as much computer work as I have to to get by, but no more. It's just not something I like to do anymore. I'm not saying I think work has to be fun, but it's better that way, if you can get by. The reason for getting rid of the Kubota and replacing it with the EarthForce is pretty much evenly split between getting more power, more maneuverability, and more versatility. It's a tall order, but I think the EF-5 is going to fit the bill - with some enhancements, of course. /w3tcompact/icons/wink.gif

MarkC

 

[allmobile]

Kubota uses variable displasement hydraulic pumps on their KX series excavators. They work very well. you can use larger displacement pumps with lower HP since as the hydraulic pressure goes up GPM goes down.

Brian

 

[MChalkley]

Brian - That's interesting info. Do you know what kind of pump they use? I didn't think they used piston pumps on the implement side of things because of their sensitivity to contaminants.

MarkC

 

[paccorti]

Mark,

HST pump and motor are contained in the same housing (much like a Kubota I expect). Here is a scan from the manual. Notice the pump and motor in the bottom picture.

Peter

 

[paccorti]

Here is more detail on the motor. Notice that it has two positions.

Peter

 

[MChalkley]

Peter - Very interesting. Thanks for the scan! Sorry to be a pest, but if you get a chance sometime, see if there's a manufacturer plate or something on the housing that would indicate who the manufacturer is.

(BTW, you're right about the Kubota: it's built the same way the NH is. The EarthForce EF-5 uses a separate Rexroth pump and motor design.)

MarkC

 

[paccorti]

Here is the operation of the motor in the low speed (high displacement position).

Peter

 

[paccorti]

Mark,

I crawled around under there but did not see any obvious manufacturer identification...

So I'll bet you went through quite the selection press with regards to the new machine. I guess an L48 was not enough. This should open a new class of jobs for you (and close some others, no more PTO right?)

Peter

 

[MChalkley]

Peter - Thanks again - I didn't realize so much more info was coming! That tells me a lot. FWIW, the EF-5 Rexroth motor varies continuously from 0 to 25 degrees (with high torque mode forced to 25 degrees), while the pump varies continously from 0 to 35 degrees.

MarkC

 

[MChalkley]

Peter - Once again, thanks!!! I didn't mean tonight. /w3tcompact/icons/blush.gif

Yeah, it was an interesting 2 and a half months that I spent researching this decision. At least a dozen trips to all the equipment dealers I could find in Richmond and Hampton Roads, VA areas (and that's a bunch), plus 4 700 mile round trips to Tazewell, VA to look at the PowerTrac, and then a 7 hour round trip to Folcomer Equipment in Baltimore, MD, and culminating in a 1300 mile round trip to Summerville, SC to visit the EarthForce North American distribution facility, where I also met with the N.A. sales manager, the N.A. parts manager, the VP in charge of N.A. operations, and the President of the company himself (though seeing him was coincidental, not planned). I was very impressed with them and their equipment. I have to say, too, that I felt very strange being so impressed with the PowerTrac, then being that much more impressed by the EarthForce. I discussed the specific reasons in my initial post in the thread describing the EarthForce choice, but in the end it just underscored the engineering and construction superiority (for my purposes) of the EarthForce as compared to anything else I'd seen. I felt at first that I ought to be embarrassed to make such a change in my decision, but I finally decided that if I'd seen the EarthForce first, I wouldn't have even looked at the PowerTrac, so it wasn't indecisiveness on my part, but a lack of all the facts necessary to make the final choice. That's why I spent so much time making the decision in the first place.

As for the PTO, yes, I'll no longer have a mechanical PTO, but I'll have two hydraulic PTO, one on each end. Speaking of which, a friend of mine who owns an excavation company (and has a lot of big equipment) told me last week that he saw a hitch converter for skid steers that allows three point hitch implements to be mounted on a skid steer (sort of like the SpeeCo does), but has a hydralic motor with a PTO spline on it so you can attach a mechanical PTO shaft to it. That might solve my tiller problems, so he's trying to find it again - he doesn't remember where he saw it. If he does, I'll post it on TBN, of course.

MarkC