Tractor hydraulics and running implements

[dstig1]

I think I am starting to catch on, but still a bit confused on this, and if what I am thinking of doing would work. I had a thread on mounting a rotary broom on my FEL a while back here:
https://www.tractorbynet.com/forums/kubota-owning-operating/395975-grand-l-5240-rotary-broom-2.html

That started to get into the potential for running it off the rear remotes from the main tractor hydraulics. So here is what the tractor specs say:



As you can see from the chart, the hydraulic pump has 2 separate sections so steering is isolated from the rest of the system. And the main pump is 9.4 GPM. I am not sure if 9.4 is enough to run a 6' brush or not yet, so that is one big question. The next big question is around what that 9.4GPM does right now - what is it running on the tractor. The tractor is HST, so the drive is its own separate system, as is the steering, already noted. So obviously when I raise or lower the FEL, 3 pt pr TNT, it is driving that, but otherwise is it actually doing anything other than circulating fluid through the system and waiting for one of those valves to open? If that is the case, then it appears that the entire 9.4GPM would be available to run the broom, except when I move the FEL or 3pt, for example. So if that is indeed true, then I mainly need to find what broom I can drive with 9GPM or so (at whatever pressure it is making - which is also unclear to me but sounds like ~2500psi is about typical).

So is that right, or am I off base here?

Thanks,
Dave

 

[Rich B1]

You most likely have an open center hydraulic system. The implement oil simply flows from pump to tank until oil is required by a valve in the system. Very common and simple.

9.4 GPM is too little to drive a sweeper from a quick look I did on a sweeper. You will likely need 15 -25 to run one efficiently. If this is part time use, a PTO driven pump will get you there. But you will need a reservoir and filter to go with it.

 

[dstig1]

Thanks, Rich. It sounds like I am indeed starting to catch on with all this hydraulic stuff...:thumbsup:

I may have found something that meets the tractor system ratings. Page 7 of this PDF, model MRHL looks like just what I need and has options that work at 8-15GPM
https://www.paladinattachments.com/...lit/BR - PA - compact tractor attachments.pdf

 

[rScotty]

You most likely have an open center hydraulic system. The implement oil simply flows from pump to tank until oil is required by a valve in the system. Very common and simple.

9.4 GPM is too little to drive a sweeper from a quick look I did on a sweeper. You will likely need 15 -25 to run one efficiently. If this is part time use, a PTO driven pump will get you there. But you will need a reservoir and filter to go with it.

I agree. Open hydraulics are what it has, and 9.4 GPM is too little to run a sweeper for anything more than sweeping off a short driveway - and marginable at that. If you look deeper into compact tractor hydraulics you'll find that they are for part time use, not continuous duty at full flow. For continuous duty on a medium sized tractor most use a separate PTO driven pump with its own fluid supply reservoir, it's own pump, and hopefully some filtration and cooling. Cooling is important.
If what you want is continuous highpressure/high volume hydraulic flow along with enough engine power left over to drive around at the same time, there just isn't much until you get up closer to the 100 hp range.
rScotty

 

[dstig1]

I called the guys at Paladin attachments, from what i posted above. They agreed with you that I would really need a PTO pump to make this work. While that would surely do it, I would lose my ability to have the rear blade on. I am really trying to get both on there at once - brush plus rear blade - so once I am set up for winter, the only thing I might need to do is drop the brush and grab the bucket if we get a lot of snow piling up.

This then gets me into my thinking around driving a pump off the mid PTO, which starts to get very complicated itself as it would be a custom setup, as best i can tell. I'm OK with that, but it obviously takes more time and effort. Or just mount a 13hp gas motor on it and drive it directly from that... But the costs of this whole setup were getting pretty crazy too. I dunno...:confused3:

 

[oldnslo]

Dave
Is there an option to run the brush with the mid PTO? I suspect this would require some form of mounting brackets but would provide full mechanical PTO power for the brush.

I believe this is an option for some models of tractors.

 

[LouNY]

You could mount the hydraulic reservoir on the front or side of the tractor,
then just the pump on the pto and lines running forward.
That would leave your lift arms open and available.

 

[Tags]

You could also get a rear mounted broom that runs off the pto and put a blade on the front....

 

[dstig1]

Thanks but my neck couldn't handle having to look backwards that much. The rear blade doesn't require too much turning around, but a brush would require constantly looking back.

I will freely admit that there are many ways to skin this cat, but I have come to the point I am at because none of the other options solve the full problem like this one does.

 

[Tags]

Unfortunately you will not have enough flow to run a broom efficiently. Even if you go by the low end of the flow required, it will constantly stall and you will be very unhappy with the performance. You may be able to find a pump and tank combo compact enough to put on the back that will run off the pto and fit between the three point hitch so you can still use the blade, but it will be a tight fit I think.