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wanabe
01-26-2010, 05:48 PM
Will a standard flow T300 run a bush hog type mower or will it not have enough hyd flow? Not mowing anything other than tall grass. Thanks

AWJ Services
01-26-2010, 06:07 PM
Yes it will do pretty good.
Keep the blades sharp.

curtisfarmer
01-26-2010, 06:17 PM
Out of curiosity, how many GPMs do you need for say a 5' or 6' QA rotary mower?

sawinredneck
01-26-2010, 06:22 PM
8gpm will run it, 12gpm will run it right.

AWJ Services
01-26-2010, 06:55 PM
GPM need to be converted to hp to get a realitive term for comparrison.
GPM by itself means nothing. You have to have pressure as well.

Hyd hp = gpmxpsi/1714

20 GPM at 3000 psi= 35 hp

To pull a 5 foot bush hog behind a tractor you need 30 hp min to be effective.

I think the T300 puts out 20.7 GPM standard flow.

Barge Man
01-26-2010, 07:00 PM
I would run our 6' bush hog on our T190 which was standard flow and it would do just fine. Our T300 doesent even know it on their:laugh: Hope this helps out.

Guest441
01-26-2010, 07:30 PM
Hydro drive bush hogs?
Isn't that what the 540 PTO is for?

sawinredneck
01-26-2010, 07:54 PM
Skid steers don't have PTO.
Your conversion works for HP but not torque and in an all hydro machine you loose 15% of the HP to drive transference right off the bat.
IF you find a manufacture that produces 3000psi factory let me know, they should be shut down! That is the "theoretical" operating pressure, but not realistic as it puts most components at burst capacity all the time. 2650 is more what you will see on most machines.
You also have limited fluctuation in speed with a hydro unit unless you completely overload the system, which is doable.
Also, I've yet to see a reasonable sized skid steer putting out 20, much less 30gpm! I can get that from a hydrostatic unit, but not hydraulic!

bobcat_ron
01-26-2010, 09:00 PM
Take a torch and open up the deck as much as possible so it cuts better in thick grass, it it's a Bobcat brush mower, just cut then entire deck away leaving only the motor, spindle and quick attach frame, they aren't the best. :laugh:

wanabe
01-26-2010, 09:37 PM
What im thinking about doing is putting a hydaulic motor om my woods 72 inch bush hog that I no longer use on the tractor due to the fact that I have a 15 foot batwing now. Was thinking the skid mounted unit would be nice to mow arround crap due to the hydro and being alot quicker that the tractor in tight spots. Now I just need to find a motor. I sure hope it cuts better than a 35 hp tractor on this mower. I have had it on a 85 hp tractor and that was about right. Thanks

AWJ Services
01-26-2010, 09:53 PM
Skid steers don't have PTO.
Your conversion works for HP but not torque and in an all hydro machine you loose 15% of the HP to drive transference right off the bat.
IF you find a manufacture that produces 3000psi factory let me know, they should be shut down! That is the "theoretical" operating pressure, but not realistic as it puts most components at burst capacity all the time. 2650 is more what you will see on most machines.
You also have limited fluctuation in speed with a hydro unit unless you completely overload the system, which is doable.
Also, I've yet to see a reasonable sized skid steer putting out 20, much less 30gpm! I can get that from a hydrostatic unit, but not hydraulic!

So what proof do you base this off of?

Digdeep
01-26-2010, 10:00 PM
Skid steers don't have PTO.
Your conversion works for HP but not torque and in an all hydro machine you loose 15% of the HP to drive transference right off the bat.
IF you find a manufacture that produces 3000psi factory let me know, they should be shut down! That is the "theoretical" operating pressure, but not realistic as it puts most components at burst capacity all the time. 2650 is more what you will see on most machines.
You also have limited fluctuation in speed with a hydro unit unless you completely overload the system, which is doable.
Also, I've yet to see a reasonable sized skid steer putting out 20, much less 30gpm! I can get that from a hydrostatic unit, but not hydraulic!

I don't question that there is a significant difference between the "calculated/theoretical" hydraulic hp vs. actual hydraulic hp due to inefficiencies. However, we better start shutting these guys down because most OEMs that I'm aware of can produce oil flow through a flow meter at 3000psi- some up to almost 4000psi :weightlifter: It's the amount of flow that is in question. What do you figure the high flow pumps on skid steers put out through a rotary deck without a load on it? I'm betting that once you overcome the 1000psi or so it probably takes to spin the deck it is close to 80% of their advertised flow, but probably not close to their advertised pressure because you can't really load up a rotary, especially if it has swinging blades. The pressure that the pump feels is much greater on a mulching head that feels direct resistance from say a tree trunk, or a cold planer that is trying to turn a drum against asphalt.

Don't take this the wrong way, but I think you need to get out to see some more "reasonably sized" skid steers operating with hydraulic attachments such as trenchers, flails, snow blowers, cold planers, etc. You'd be shocked at what they can do. :drinkup:

sawinredneck
01-26-2010, 10:00 PM
Link one:

http://www.engineeringtoolbox.com/pumps-power-d_505.html

BRB, need to get my Bobcat manuals out of the garage for the pressure test numbers.

sawinredneck
01-26-2010, 10:17 PM
773G series: pump capacity at 2800RPM 16.6GPM main relief at 2900PSI @46hp

873G Series: pump capacity at 2475RPM 18.7GPM main relief at 2900PSI @73HP

980 Pump capacity at 2200RPM 12.8 and 25GPM main relief at 2250PSI @94HP

1213 (feller buncher) pump capacity at 2600RPM 16 and 7GPM relief set at 2700 and 2200PSI @62HP

The higher numbers are at couplers with steel lines, no soft lines for pressure tests.

Digdeep
01-26-2010, 10:58 PM
773G series: pump capacity at 2800RPM 16.6GPM main relief at 2900PSI @46hp

873G Series: pump capacity at 2475RPM 18.7GPM main relief at 2900PSI @73HP

980 Pump capacity at 2200RPM 12.8 and 25GPM main relief at 2250PSI @94HP

1213 (feller buncher) pump capacity at 2600RPM 16 and 7GPM relief set at 2700 and 2200PSI @62HP

The higher numbers are at couplers with steel lines, no soft lines for pressure tests.

Old machines. Here is a link to a thread that a guy "RidinAround" posted well over a year ago on here. It has a page that shows flows, pressures and hydraulic hps for a couple OEMs above the limits you mentioned-
http://www.lawnsite.com/attachment.php?attachmentid=98356&d=1201629168

ksss
01-26-2010, 11:03 PM
Old machines. Here is a link to a thread that a guy "RidinAround" posted well over a year ago on here. It has a page that shows flows, pressures and hydraulic hps for a couple OEMs above the limits you mentioned-
http://www.lawnsite.com/attachment.php?attachmentid=98356&d=1201629168


I am making 3900 psi at the high flow with 40 gpm. It specs 41.9 but I don't get that much. The reliefs have been changed out to get the higher pressures. This is on a 465. My 440 was tested a couple weeks ago and makes 22gpm at the aux. I have not tested my 465 at the aux. I think your numbers are off or maybe old or something.

YellowDogSVC
01-26-2010, 11:37 PM
773G series: pump capacity at 2800RPM 16.6GPM main relief at 2900PSI @46hp

873G Series: pump capacity at 2475RPM 18.7GPM main relief at 2900PSI @73HP

980 Pump capacity at 2200RPM 12.8 and 25GPM main relief at 2250PSI @94HP

1213 (feller buncher) pump capacity at 2600RPM 16 and 7GPM relief set at 2700 and 2200PSI @62HP

The higher numbers are at couplers with steel lines, no soft lines for pressure tests.

that's old school machines. Some even had 2500 psi. The new machines are much more efficient and produce greater pressures.

YellowDogSVC
01-26-2010, 11:40 PM
I am making 3900 psi at the high flow with 40 gpm. It specs 41.9 but I don't get that much. The reliefs have been changed out to get the higher pressures. This is on a 465. My 440 was tested a couple weeks ago and makes 22gpm at the aux. I have not tested my 465 at the aux. I think your numbers are off or maybe old or something.

Imagine if you were running a series 3 what you could do...? :weightlifter:

AWJ Services
01-26-2010, 11:44 PM
Link one:

http://www.engineeringtoolbox.com/pumps-power-d_505.html

BRB, need to get my Bobcat manuals out of the garage for the pressure test numbers.

So you read an article on the internet and you are now an expert?

sawinredneck
01-26-2010, 11:55 PM
It appears I am old school, but I've worked on a machine or two in my day thank you.

goblingreen
01-27-2010, 12:36 AM
RUH ROH, somebody is about to get schooled....and in 3....2...1...

ksss
01-27-2010, 12:57 AM
Imagine if you were running a series 3 what you could do...? :weightlifter:



BIC if I remember correctly is claiming around 4600 psi at 35 GPM. They say those are actual output numbers in a Series 3 450/465.

stihlboy
01-27-2010, 01:03 AM
What im thinking about doing is putting a hydaulic motor om my woods 72 inch bush hog that I no longer use on the tractor due to the fact that I have a 15 foot batwing now. Was thinking the skid mounted unit would be nice to mow arround crap due to the hydro and being alot quicker that the tractor in tight spots. Now I just need to find a motor. I sure hope it cuts better than a 35 hp tractor on this mower. I have had it on a 85 hp tractor and that was about right. Thanks

a 6' deck brush hog is gonna take some power, good luck

hvy 1ton
01-27-2010, 01:12 AM
773G series: pump capacity at 2800RPM 16.6GPM main relief at 2900PSI @46hp

873G Series: pump capacity at 2475RPM 18.7GPM main relief at 2900PSI @73HP

980 Pump capacity at 2200RPM 12.8 and 25GPM main relief at 2250PSI @94HP

1213 (feller buncher) pump capacity at 2600RPM 16 and 7GPM relief set at 2700 and 2200PSI @62HP

The higher numbers are at couplers with steel lines, no soft lines for pressure tests.

Well i was going to make a really good argument right about now, but bobcat historically has not made much effort to publish hydraulic specs. Of course, i remember this after wasting time looking for them. Anyway, are you really suggesting that manufacturer's are lying about what they set the relief pressures at or that the machines won't reach that pressure? I would like to see how long that would last before there was a pile of smoking hydraulic components. Now i'm not saying that you will get the rated flow at the rated pressure at all, but as far as i can tell that isn't what you're arguing.:rolleyes:

curtisfarmer
01-27-2010, 08:29 AM
I just got back online to read this thread....and now I am so much more informed on QA hiflow hyd.s, great details.

Alot of people here run front rotatry QA mowers? I would like to hear reviews if posible. I want to run 1 upfront on TLB, will look up PSI/flo.

I have a Woods 5' and 6', LP 7'. I use a Ford 3400 and L48, both of which are probably around 38-40hp at PTO. 5', like butter thru 3" brush, 6' no problems thru light brush and anything else,......7'.....too big for my stuff. I bought it for $700, worth like $4k, in case our current hay contractor gives up and I need to mow 30 acres at my house;)

YellowDogSVC
01-27-2010, 10:02 AM
Take a torch and open up the deck as much as possible so it cuts better in thick grass, it it's a Bobcat brush mower, just cut then entire deck away leaving only the motor, spindle and quick attach frame, they aren't the best. :laugh:

I hope you never venture down to North Dakota! :usflag::hammerhead: :laugh:



Alot of people here run front rotatry QA mowers? I would like to hear reviews if posible. I want to run 1 upfront on TLB, will look up PSI/flo.
;)

I probably have a couple thousand hours or more mowing with a Bobcat brushcat. I had a few hundred hours on Davco but it was more for the bigger stuff.
Up to 3-4 inches, the brushcat does a good job. In grass, with relatively sharp blades, it does a real good job. Thick grass, though, at only 16 gpm on my toolcat the results are just okay. On my Bobcats, at 20-23gpm it did a much better job. kick it into high flow (I had the 26 gpm model on the toolcat) and it did a very good job and will power through thick, wet coastal grass which is the toughest grass I've come across in central texas because of how it swirls.

AWJ Services
01-27-2010, 10:04 AM
What im thinking about doing is putting a hydaulic motor om my woods 72 inch bush hog that I no longer use on the tractor due to the fact that I have a 15 foot batwing now. Was thinking the skid mounted unit would be nice to mow arround crap due to the hydro and being alot quicker that the tractor in tight spots. Now I just need to find a motor. I sure hope it cuts better than a 35 hp tractor on this mower. I have had it on a 85 hp tractor and that was about right. Thanks

You can acyually buy a hyd motor with splines for the pto drive shaft.

YellowDogSVC
01-27-2010, 10:04 AM
BIC if I remember correctly is claiming around 4600 psi at 35 GPM. They say those are actual output numbers in a Series 3 450/465.

I know. I know. I know... jealous:cry: I am fairly certain modern components can handle it. Whenever I need a replacement hose, the hoses are overrated for my pressures.

AWJ Services
01-27-2010, 10:19 AM
The problem with hyd specs on aux lines is as far as I can tell is not many actually tests the flow with an attachment on front while in use. You can buy a hyd flow meter that will log the pressure and flow to a computer and at the end of the day download your data log and get a real world number. '
As Digdeep said different attachments load the hyd system different ways.
It is no different then your engine in your equipment. Just because it is rated at 85 hp does not mean that is how much power it is putting out at a given time. You run it at full throttle with no load and it may only have 22 hp.
Hyd specs are supposedly what the machine will do under a predetermined set of conditions just as are your engine ratings. You take an engine to pikes peak and it will not develop the same power as it will on the Florida coast. Same with your HYd system. As temp raises , altitude changes, load changes so will the hyd output.

Standard hyd test meters are just a flow meter with a pressure regulator and a temp gauge. You set the pressure to 3000 psi and log your flow. How can that be inaccurate? Here is OTC's testers instructions on how to use it.

http://cache01.voyageurweb.com/otctools.com/newcatalog/products/102898.pdf

Time for recess.:)

Construct'O
01-27-2010, 10:44 AM
You can acyually buy a hyd motor with splines for the pto drive shaft.

If you could find a motor like this i think you would be happier with your mower.Easier too mount,the gear box would help,i think in power as a reduction from hydraulic to manual in performence more like direct drive by PTO.

Motor would work as slip clutch if you hit something,we all know how great the old slip clutchs work(don't),then there are the shear pins:laugh:

Still would have to maintain the gear box with oil and the seals at the bottoms(joke),but too me seems it would make your conversion fairly easy:usflag:

sawinredneck
01-27-2010, 10:50 AM
Well i was going to make a really good argument right about now, but bobcat historically has not made much effort to publish hydraulic specs. Of course, i remember this after wasting time looking for them. Anyway, are you really suggesting that manufacturer's are lying about what they set the relief pressures at or that the machines won't reach that pressure? I would like to see how long that would last before there was a pile of smoking hydraulic components. Now i'm not saying that you will get the rated flow at the rated pressure at all, but as far as i can tell that isn't what you're arguing.:rolleyes:

The machines I am familiar with don't reach those pressures, no. I'm not going to say they can't, but I certainly would think there would be some issues using older attachments with these new high pressure systems. The old hoses where rated a 3000psi with a rupture at 3500psi. It was also pretty well beat into every mechanic's head that was pretty much maxing out the rubber hoses at the time.
I am aware that technology is always improving, but I am also aware that manufactures have been know to inflate numbers to help sales over a competetor as well.

I don't have much time running a Brushcat, lots of time fixing them, but the times I did run them, they had plenty of power for "normal" brush hogging. They do make a chain flail mower for larger stuff.

AWJ Services
01-27-2010, 10:57 AM
If you could find a motor like this i think you would be happier with your mower.Easier too mount,the gear box would help,i think in power as a reduction from hydraulic to manual in performence more like direct drive by PTO.

Motor would work as slip clutch if you hit something,we all know how great the old slip clutchs work(don't),then there are the shear pins:laugh:

Still would have to maintain the gear box with oil and the seals at the bottoms(joke),but too me seems it would make your conversion fairly easy:usflag:

https://www.surpluscenter.com/item.asp?UID=3524012709564500&item=9-7368-100&catname=hydraulic

They make different sizes as well.

sawinredneck
01-27-2010, 11:01 AM
https://www.surpluscenter.com/item.asp?UID=3524012709564500&item=9-7368-100&catname=hydraulic

They make different sizes as well.

And if you look they have several that run right around 540RPM:)

wanabe
01-27-2010, 11:34 AM
Can anyone compare a 72 inch hyd drive motor(skid mower) vs a 72 inch pto driven(85 hp) mower? Im thinking performance is just not going to do it for me. Im glad this site is here. Had no way of knowing that a 80+ hp skid had so little hydraulic hp. Thanks

AWJ Services
01-27-2010, 11:44 AM
Can anyone compare a 72 inch hyd drive motor(skid mower) vs a 72 inch pto driven(85 hp) mower? Im thinking performance is just not going to do it for me. Im glad this site is here. Had no way of knowing that a 80+ hp skid had so little hydraulic hp. Thanks


The primary task of the engine is for excavation. Aux flow is an after thought. Excavators are really a better platform for hyd attachments as they only have to generate enough flow to move the boom. My excavator has 48 HP and does 20 GPM.

sawinredneck
01-27-2010, 12:02 PM
Rent or demo one for a day wanabe, try it on your machine and see. I think you will be surprised at what they really can do, and if you don't like it you aren't out much if anything. Most dealers are so slow right now a demo shouldn't be hard to get.

curtisfarmer
01-27-2010, 03:20 PM
Our local rental yard just got a 72" QA hyd. rotary and I want to try that upfront to compare to a rear pto.

I am not knowledgeable on adjusting flow to act as slip clutch but i guess my question would be is hyd force greater in torque than a shaft pto....or is it back to relief pressure and how tight is your slip clutch??

sawinredneck
01-27-2010, 04:22 PM
With the hyd units, much like the larger PTO drives, it bogs the engine down or shears the bolt, very seldom do you stall them from what I've seen.

ksss
01-27-2010, 06:53 PM
The machines I am familiar with don't reach those pressures, no. I'm not going to say they can't, but I certainly would think there would be some issues using older attachments with these new high pressure systems. The old hoses where rated a 3000psi with a rupture at 3500psi. It was also pretty well beat into every mechanic's head that was pretty much maxing out the rubber hoses at the time.
I am aware that technology is always improving, but I am also aware that manufactures have been know to inflate numbers to help sales over a competetor as well.

I don't have much time running a Brushcat, lots of time fixing them, but the times I did run them, they had plenty of power for "normal" brush hogging. They do make a chain flail mower for larger stuff.


Your right there are issues. I had 1840's in the early and mid 90's as I traded out of those machines and into the XT series I was blowing hyd motor seals on a regular basis. Most of my attachments (Rock Rakes) were speced for 2500 psi which was the 1800 series press spec. The XTs were 3K. It caused problems until I got rid of those attachments.

ShawnH
01-27-2010, 10:39 PM
The performance of my CAT 289 with the 72" standard flow mower is more than what most tractors can take on with a standard PTO mower.

http://img.photobucket.com/albums/v308/shender944/Photo_093009_002.jpg

wanabe
01-27-2010, 10:42 PM
The performance of my CAT 289 with the 72" standard flow mower is more than what most tractors can take on with a standard PTO mower.

http://img.photobucket.com/albums/v308/shender944/Photo_093009_002.jpg

Thats a sharp looking skid!

ShawnH
01-27-2010, 11:57 PM
Thank you wanabe that was within her first 5 hours. After a couple hundred hours in the woods she isn't so shinny anymore. :laugh:

curtisfarmer
01-28-2010, 08:18 AM
My PTO mowers would go thru that stuff....and more. I wish I could pick them up and drop them on big stuff, thats why I want one up front.

ShawnH
01-28-2010, 10:24 PM
The mower I posted above has around a 1000 hard hours on it and needs to have the motor rebuilt. It has been lacking power and finally started leaking on me last week. We have taken out allot of small trees with it over the years its amazing how much abuse then can take.

wanabe
01-28-2010, 11:12 PM
The mower I posted above has around a 1000 hard hours on it and needs to have the motor rebuilt. It has been lacking power and finally started leaking on me last week. We have taken out allot of small trees with it over the years its amazing how much abuse then can take.


Is there any way you could post the MfG and motor part number? Does yours have a hyd valve inline as well? Thanks

ShawnH
01-28-2010, 11:26 PM
Is there any way you could post the MfG and motor part number? Does yours have a hyd valve inline as well? Thanks

I have no idea what the part number is on the motor but I will find out when we pull it to have it serviced next week. The mower is a CAT BR 172 they are made by Timberwolf for CAT looks like its model 7200
http://www.brushwolf.com/pages/modelpages/7200.html