Anyone know what the flow through the dealer installed BX2419 rear remotes for the 2020 Kubota BXs is? The total for the BX2680 published is 6.2 gpm but I can’t find the usable at remotes published. The power steering obviously takes some of it. Looking at getting a hydraulic motor for a fence line mower project and I want to get the right size. I saw some older posts saying it’s around 3.2gpm but I’m wondering if it’s improved. Thanks!
BX2419 rear remote flow?
- Thread starter corym
- Start date
With the open center design of your hydraulic system, except if the power steering is using some, the total flow is available but remember this is at max rpm's. which is noisy.
Driving hydraulic motors is a tricky issue with farm tractors. Heat build up is a big one as the tractors were not designed to deal with hydraulic loads which occur for long periods. For example, you raise the 3 pt. hydraulic task finished. You power a motor, hydraulic power requirements continue for as long as the motor runs.
Skid steers and such are built to deal with the heat.
Look at the pto driven hydraulic power pack and note the size of the cooling fan and radiator just to keep oil temps under control.
The rear ports on tractors are designed to operate cylinders not motors. The spool in the valve for a motor is different.
With a cylinder, when the control lever is returned to the neutral position, the cylinder stops moving.
With a motor with an inertial load from a blade or impeller, motors do not like having the flow cut off abruptly as it forces an immediate stop not a coasting stop.
The bigger the motor and heavier the rotating load the more serious this becomes.
Cylinder spool: work ports blocked in neutral. Motor spool: work ports connected to tank in neutral. ... If you are using the motors for propulsion they need to be blocked in neutral, not connected to the tank.
I am not saying your plan will not work but rather be aware of the shortcomings and plan for them in your design.
Dave
Driving hydraulic motors is a tricky issue with farm tractors. Heat build up is a big one as the tractors were not designed to deal with hydraulic loads which occur for long periods. For example, you raise the 3 pt. hydraulic task finished. You power a motor, hydraulic power requirements continue for as long as the motor runs.
Skid steers and such are built to deal with the heat.
Look at the pto driven hydraulic power pack and note the size of the cooling fan and radiator just to keep oil temps under control.
The rear ports on tractors are designed to operate cylinders not motors. The spool in the valve for a motor is different.
With a cylinder, when the control lever is returned to the neutral position, the cylinder stops moving.
With a motor with an inertial load from a blade or impeller, motors do not like having the flow cut off abruptly as it forces an immediate stop not a coasting stop.
The bigger the motor and heavier the rotating load the more serious this becomes.
Cylinder spool: work ports blocked in neutral. Motor spool: work ports connected to tank in neutral. ... If you are using the motors for propulsion they need to be blocked in neutral, not connected to the tank.
I am not saying your plan will not work but rather be aware of the shortcomings and plan for them in your design.
Dave
That’s great feedback thank you Dave. Heat is a concern but I’ve searched around and have not been able to calculate it. I was thinking I’ll just get a motor and try it and watch the temp. Given the little plastic fan doing the cooling on the BX I am a bit worried.
I was thinking of getting a small parker Motor
https://www.surpluscenter.com/Hydra...ker-MGG20010-BB1A3-Hydraulic-Motor-9-8499.axd
and a relief valve.
SAE 12 30 GPM Hyd Motor Relief Bypass Valve Fluidtech FTA1382 | Relief & Cushion Valves | Hydraulic Valves | Hydraulics | www.surpluscenter.com
SAE 12 30 GPM Hyd Motor Relief Bypass Valve Fluidtech FTA1382, Relief & Cushion Valves, SAE 12 30 GPM HYDRAULIC MOTOR RELIEF BYPASS VALVE Brand new,Fluidtech,FTA1382 ,
www.surpluscenter.com
I just need to spin a string trimmer head at ~3000 rpm or a small lawn mower blade.
I have a three acre vineyard and the time to string trim under all the vines is about 26 hours multiple times per year. Having a small hydro powered string trimmer on a flexible arm off the rear of the tractor would really save some time. If I have to get one of the pto powered hydro pumps I’ll probably just scrap the hydro idea and try and build something pto with belts, a little more challenging. Thanks again for the input.
Often new owners find owning a tractor is seen as a solution to every task.
A cheap Chinese gas engine can provide a wealth of flexibility to a design.
Wood splitters always come up. A new owner with a $30,000 tractor wants to crank on the operating hours driving a wood splitter using the tractor hydraulics.
A gas engine driving a two stage pump wont cost any more than a scheduled maintenance on the tractor.
Keep an open mind ,,,,,,,,,,,,,
Dave
I get your point. I was just trying to keep things as simple as possible and as economical as possible. I’ve seen some fully self contained units with on board pto driven hydraulic system but they are unfortunately out of my price range.
Would there be any benefit to connecting to the front loader hydraulics as opposed to the back rear remotes? It looks like this BX2350 is able to handle running a hydraulic motor on the front. Although maybe the hydraulic specs were different on the 2350 series compared to the 2680. I’ll have to look it up. Seems like heat build up concerns would be an issue not dependent on the connection point.
Regardless of where you connect into the hydraulic system the same issues remain.
As someone else pointed out, each time you move the loader the trimmer motor's flow is cut off.
I have seen post hole drills working of loader hydraulics but they are a low speed high torque application.
Dave