BX25 hydraulic flow rate

Dougsshed

New member

Equipment
BX25, 4in1 FEL, b/hoe,grader, single tyne ripper, 60" mower, carry-all
Kubota specs tell me that the hydraulic pump has an output, at the pump, of 6.3 gpm or 24L/min. Does anyone know what this translates to at the rear couplings for the backhoe? Is it significantly less? I'm buying a hedge trimmer that needs 20L/min and I don't want to buy it and find out that the hydraulics struggle to work the cutter head.
Alternatively, does anyone know of a flow meter that would fit the BX25 couplings?
 

conropl

Member

Equipment
L3560 HSDC
Oct 17, 2016
233
18
18
West Michigan
The power steering will take about 2 GPM of the total flow produced. So that leaves you with about 4.3 GPM of usable flow. That's how I understood it works.

Sent from my SM-J737V using Tapatalk
 

Dave_eng

Well-known member
Lifetime Member

Equipment
M7040, Nuffield 465
Oct 6, 2012
5,106
926
113
Williamstown Ontario Canada
As Conropol said, the pump output is divided to ensure the power steering always has sufficient flow:

The following from the WSM.

The flow priority valve is a flow divider that divides single hydraulic source (hydraulic pump) to actuates two circuits simultaneously.
This valve feeds fixedly controlled flow (8.0 Llmin., 2.1 U.S.gals.lmin., 1.8 Imp.gals./min.) to the PF port with priority and excessive flow to the EF port.

Unfortunately, when you do not use the power steering the prioritized flow is just dumped into the reservoir and is of no use for your other needs.

Hydraulic pump is driven by the pump drive shaft in
the transmission case. Maximum displacement is as follows.
Displacement 23.5 l, 6.2 U.S.gals, 5.2 Imp.gals. per minute
Engine speed 3200 rpm
Condition at no load


So in brief 1/3 of your pump's output is prioritized to the power steering.

This leaves you at the very best 15.5 L per minute.
I have a Samurai sicklel mower whose flow and pressure requirements are:

To function correctly, the Samurai requires 0.4 to
1.0 hp (0.3 to 0.8 kW). The hydraulic oil flow
required at an operating speed of 250 rpm is 3.3
gal/min (0.21 L/s). Hydraulic pressure during
normal operation is less than 500 psi (3 450 kPa).
A hydraulic pump supplying at least 5 gal/min (0.3
L/s) should have adequate flow to operate the
Samurai. Most tractor and equipment hydraulic
systems can easily supply this oil flow without
affecting the performance of other hydraulically
driven components.

FYI:

0.3 litres per second is 60 x 0.3 equals 18 litres per minute.

or still too low for your BX25

Dave
 

Kennyd4110

Well-known member
Vendor Member
Sep 7, 2013
1,164
329
83
Westminster, MD
www.boltonhooks.com
Good advice so far...
I wish all OEM's would start offering real usable GPM's on our smaller tractors, that would be a great selling point rather that so much horsepower in a small lightweight machine that you can't get to the ground because the tires just spin.

FYI, just about any flowmeter will work with your BX with the correct QD's, but flow meters are expensive so they are out of reach for the average guy.
 

Dougsshed

New member

Equipment
BX25, 4in1 FEL, b/hoe,grader, single tyne ripper, 60" mower, carry-all
Good advice so far...
I wish all OEM's would start offering real usable GPM's on our smaller tractors, that would be a great selling point rather that so much horsepower in a small lightweight machine that you can't get to the ground because the tires just spin.

FYI, just about any flowmeter will work with your BX with the correct QD's, but flow meters are expensive so they are out of reach for the average guy.
Thanks Kenny. Yeah, I've realised, with the above info, that a flow meter is a waste of time for me. It's just going to tell me what I've already been told above and that's that the available flow, after the pwr steering is covered, is not enough :-(
Still, can't complain too much. It's a great little tractor and versatile.
 

Kennyd4110

Well-known member
Vendor Member
Sep 7, 2013
1,164
329
83
Westminster, MD
www.boltonhooks.com
Thanks Kenny. Yeah, I've realised, with the above info, that a flow meter is a waste of time for me. It's just going to tell me what I've already been told above and that's that the available flow, after the pwr steering is covered, is not enough :-(
Still, can't complain too much. It's a great little tractor and versatile.
There is one other way, albeit also expensive...You could build or buy a PTO driven "power pack" that consists of as PTO driven hydraulic pump, a tank, a cooler (maybe), and a control valve.

http://www.erskineattachments.com/hydraulic-power-unit

https://www.loftness.com/products/other-attachments/hydraulic-power-unit/power-pak/overview

This one should be the most affordable, we say it at the National Farm Machinery Show, not sure what the "street" price is though.

Edit: Whoops I see you're in Australia though...

http://trailblazerattachments.com/tb-power-kit.html
 
Last edited:

OLD GAR

Member

Equipment
MF210, FORD 8N, BIG TEX CH18,
Aug 3, 2015
69
5
8
ZWOLLE
So my recent purchase of a BX2350 is going to be limited to a high rpm to activate the two functions of the FEL? Even at 2500rpm it won't curl and lift at the same time. I'm going to change the filter today and see in that improves the hydraulic power.

Number two question. . . How, or is it possible, to stop the mower deck from descending to ground when I only want the 3 point to drop or descend to a desired height. Thanks
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
28,286
4,851
113
Sandpoint, ID
So my recent purchase of a BX2350 is going to be limited to a high rpm to activate the two functions of the FEL? Even at 2500rpm it won't curl and lift at the same time. I'm going to change the filter today and see in that improves the hydraulic power.

Number two question. . . How, or is it possible, to stop the mower deck from descending to ground when I only want the 3 point to drop or descend to a desired height. Thanks
It could very well be that your valve is made to not curl and lift at the same time, it is a standard valve setup that limits the danger of dumping material off the back of the bucket onto the hood or the operator.

Yes you can lock the mower deck upo and still use the three point, look in the operator's manual for the tractor/deck and it should explain how to lock it up as they are all a little different.
 

Dougsshed

New member

Equipment
BX25, 4in1 FEL, b/hoe,grader, single tyne ripper, 60" mower, carry-all
Thanks Kenny. As you noted, I'm in Oz. Certainly would be a good option if I thought I would get enough use to justify the cost. The availability of items like that is much more limited here. But a good thought. Thanks
 

RCW

Well-known member
Lifetime Member

Equipment
BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
Apr 28, 2013
8,282
3,865
113
Chenango County, NY
So my recent purchase of a BX2350 is going to be limited to a high rpm to activate the two functions of the FEL? Even at 2500rpm it won't curl and lift at the same time. I'm going to change the filter today and see in that improves the hydraulic power.



Number two question. . . How, or is it possible, to stop the mower deck from descending to ground when I only want the 3 point to drop or descend to a desired height. Thanks

If you look at your loader, you will likely find a graphic like my BX2360. No dual-function for lift/curl. See photo, bottom left of graphic is blank.

Honestly, I notice a short delay sometimes but it’s not a problem for me.

Like Wolfman said the height adjustment knob under the seat probably has a TOP setting. It might need some adjusting to get it to lock it up.

Get a workshop manual (WSM) at www.kubotabooks.com




Sent from my iPhone using Tapatalk
 

GeoHorn

Well-known member
Lifetime Member

Equipment
M4700DT, LA1002FEL, Ferguson5-8B Compactor-Roller, 10KDumpTrailer, RTV-X900
May 18, 2018
5,570
2,936
113
Texas
It could very well be that your valve is made to not curl and lift at the same time, it is a standard valve setup that limits the danger of dumping material off the back of the bucket onto the hood or the operator.

Yes you can lock the mower deck upo and still use the three point, look in the operator's manual for the tractor/deck and it should explain how to lock it up as they are all a little different.
If you look at your loader, you will likely find a graphic like my BX2360. No dual-function for lift/curl. See photo, bottom left of graphic is blank.

Honestly, I notice a short delay sometimes but it***8217;s not a problem for me.

Like Wolfman said the height adjustment knob under the seat probably has a TOP setting. It might need some adjusting to get it to lock it up.

Get a workshop manual (WSM) at www.kubotabooks.com



Sent from my iPhone using Tapatalk
That sticker indicates the bucket DOES AND SHOULD lift/curl or descend/curl simultaneously, the way I read it.
This is one of the great selling points of Kubota FELs.
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
28,286
4,851
113
Sandpoint, ID
That sticker indicates the bucket DOES AND SHOULD lift/curl or descend/curl simultaneously, the way I read it.
This is one of the great selling points of Kubota FELs.
Negative, this is why there is no picture or arrow in the bottom, left, 45 degree corner, as it does not lift and curl simultaneously. ;)
 

GeoHorn

Well-known member
Lifetime Member

Equipment
M4700DT, LA1002FEL, Ferguson5-8B Compactor-Roller, 10KDumpTrailer, RTV-X900
May 18, 2018
5,570
2,936
113
Texas
Negative, this is why there is no picture or arrow in the bottom, left, 45 degree corner, as it does not lift and curl simultaneously. ;)
Aha! (That pic gets extremely fuzzy when expanded) I couldn’t read the decal clearly but now see the left side is raising and the right side is lowering (where simultaneous IS possible.)
 

Dougsshed

New member

Equipment
BX25, 4in1 FEL, b/hoe,grader, single tyne ripper, 60" mower, carry-all
Hi Kenny, I didn't mean 'delete' the thread. Yes, I understand the usefulness of these things for future reference. But I have the info now that I was seeking, thanks to other, more learned members than myself. So, without being rude, I would be pleased to stop getting advices of answers to questions that I didn't ask :)
 

Dougsshed

New member

Equipment
BX25, 4in1 FEL, b/hoe,grader, single tyne ripper, 60" mower, carry-all
And, of course, being the blind old duffer that I am, I had no sooner hit send on my last reply than I saw the 'unsubscribe from this thread' link in the email I got. (Hangs head in shame)
Now unsubscribed from this thread :)
 

Dave_eng

Well-known member
Lifetime Member

Equipment
M7040, Nuffield 465
Oct 6, 2012
5,106
926
113
Williamstown Ontario Canada
The LA1153 loader on my M7040 seems to have the same decal.

It will lift and curl at the same time.

The loader owners' manual explains why the lower left corner of the decal is blank.

When the lever is at each corner position marked by
asterisk (*) or lower left, boom and bucket cylinders
work at the same time. However, the lower left position
(Raise & Roll back) is not recommended for scooping
because of insufficient lift force.


I am not contradicting what others have said and only wish to add more info to the discussion.

Dave
 

Attachments

Last edited: