51" broom attachment

[mistersweeper]

Hello ! I'm new here. I have just purchased a 2005 A300 with a SG60 stumpgrinder, lp bucket and 84" snow bucket. I have never owned a skidsteer before, so some of the questions I may ask might be stupid, for this I am sorry. However , I do have a question regarding putting my sweeper attachment from my jd 2210 onto my bobcat. The sweeper is driven from a mid mount pto shaft on the tractor. I want to replace the pto shaft with an orbital motor and my welder buddy will make up a mounting bracket. How do I know what orbital hydralic motor to use to get the correct speed to the broom. All I know is the pto turns at 2100 rpm. Thanks !!!!!

 

[thetool]

So I understand that you want to turn a shaft at 2100 rpm with the aux hyds on the A300?
You gotta do a little math which I'll try, somebody will correct me if I'm wrong, please
A300 aux flow is 20.7gpm, call it 20.
1 gallon=3785 cc or 231 ci, so 20 gal/min = 75,700 cc/min or 4620 ci/min, so
75,700 cc/min / 2100 rpm = 36 cc displacement, or
4620 ci/min / 2100 rpm = 2.2 ci displacement.
The displacement in either cubic inches or cubic centimeters is the motor size. That should get you close to 2100 rpm at full throttle, but there are always further considerations.

 

[mistersweeper]

So I understand that you want to turn a shaft at 2100 rpm with the aux hyds on the A300?
You gotta do a little math which I'll try, somebody will correct me if I'm wrong, please
A300 aux flow is 20.7gpm, call it 20.
1 gallon=3785 cc or 231 ci, so 20 gal/min = 75,700 cc/min or 4620 ci/min, so
75,700 cc/min / 2100 rpm = 36 cc displacement, or
4620 ci/min / 2100 rpm = 2.2 ci displacement.
The displacement in either cubic inches or cubic centimeters is the motor size. That should get you close to 2100 rpm at full throttle, but there are always further considerations.

I don't think I should need full throttle should I ? The tractor that runs it now is a 23 hp diesel john deere 2210. All that math look purdy smrt. So what motor would run the sweeper ? And does engine speed dictate hydraulic pressure on the bobcat aux hyd ? Oh ya I do want to run sweeper with aux hydraulics on the A300.

 

[thetool]

I don't think I should need full throttle should I ? The tractor that runs it now is a 23 hp diesel john deere 2210. All that math look purdy smrt. So what motor would run the sweeper ? And does engine speed dictate hydraulic pressure on the bobcat aux hyd ? Oh ya I do want to run sweeper with aux hydraulics on the A300.

Full throttle on the Bobcat with the size motor mentioned above will give you about 2100 rpm at the motor shaft that you want to build onto your sweeper.
Engine rpm will determine motor speed, not pressure. If you don't want to run the A300 at full throttle, you have to go with a higher displacement motor to get 2100 rpm.
To figure that out, you'd have to measure aux flow at whatever engine speed you want to run the bobcat, and do the math again.
Now some other considerations......the A300 has about 4x more HP than the tractor-unless you have some kind off slip-clutch or shear-bolt setup, you may need more than just the right motor.
Good Luck

 

[mistersweeper]

Full throttle on the Bobcat with the size motor mentioned above will give you about 2100 rpm at the motor shaft that you want to build onto your sweeper.
Engine rpm will determine motor speed, not pressure. If you don't want to run the A300 at full throttle, you have to go with a higher displacement motor to get 2100 rpm.
To figure that out, you'd have to measure aux flow at whatever engine speed you want to run the bobcat, and do the math again.
Now some other considerations......the A300 has about 4x more HP than the tractor-unless you have some kind off slip-clutch or shear-bolt setup, you may need more than just the right motor.
Good Luck

AH, that's a good point about the slip clutch / shear bolt.

 

[radman1]

AH, that's a good point about the slip clutch / shear bolt.

For 2100 rpm at 15 gpm, you will need a motor with 1.65 cu inches of displacement. At 18 gpm, you will need a motor with 1.98 cu inches displacement. I don't see any need to run at WOT. Shear pin may be nice, but a small broom shouldn't have much force/resistance.

 

[skidsteer.ca]

For 2100 rpm at 15 gpm, you will need a motor with 1.65 cu inches of displacement. At 18 gpm, you will need a motor with 1.98 cu inches displacement. I don't see any need to run at WOT. Shear pin may be nice, but a small broom shouldn't have much force/resistance.

Forget the shear pin www.surpluscenter.com will sell you a cross over relief valve tabout $80 that you can adjust the relief pressure to any level you want (think of it as an adjustable shear pin that automatically replaces itself instantly, for free).
It just lets the flow from the pressure hose to the broom escape ino the return hose from the broom should the pressure rise to the level you set it to relief at and therefore the broom stops if overloaded, and restarts automatically. They are also a good source for hydraulc motors and will help you with selection and tech questions