Hydraulic power pack build

[Xfaxman]

I am eventually building or buying a 60" Brush Cutter for my Mahindra 4540.

Since you mentioned "buy", There are several front mount brush hogs made. This is the brand that my wife uses on her Toolcat: Grace Manufacturing | Home of the Tree Terminator

But then you linked to a "mulcher", big difference from a brush hog. And big difference in price too.

 

[truckinfouble]

I know the link was to a mulcher, but the flow requirements are similar. I was showing how a hydraulic power pack on a 40 horse tractor could handle my needs. Of course a mulcher would be nice, but then again I haven't found a money tree or shipwreck haha

 

[Farmerford]

7.97 cu in CHAR-LYNN 104-1063 HYD MOTOR This is the same motor I used, except that it has a larger displacement to give roughly 540 rpm at your pump flow. It is probably overkill because it has a tapered roller bearing mounted shaft to tolerate a high side load and can work in most conditions without a separate case drain. The gear box shaft is 1 3/8" with a through hole and the motor is a 1 1/4" keyed shaft (surprise: the keyway on mine was 5/16, which is not the common 1/4 size, but is allowed by SAE). I coupled the motor to the gearbox with a chain coupling using a 1 1/4 inch bore on one sprocket and 1 3/8 bore on the other one. The 1 1/4 inch bore sprockets come only with a 1/4 inch keyway, so to match the sprocket to the motor shaft keyway I used a 1/4 key to fit the sprocket and then shimmed it with 1/16 shim stock to get a tight fit in the motor shaft keyway (It has been over 10 years with heavy use and has never given a problem.

 

[agjones]

Also check power-trac.com they make hydraulic equipment and forward mounted attachments including brush cutters from 48" up, tough, well made. Pricing is right there on the site....generally less expensive than other brands.

I'm a happy (professional) costumer and highly recommended them.

 

[truckinfouble]

I think I figured out how I'm going to build this. I'm gonna use a Dynamic gear pump that will give me a little over 21 GPM with my HP rating. A 30 gallon tank with a 25-50 GPM cooler and 10 micron filter. All this will be on a cradle I can hook up to my 3 point. I will run hoses that can be attached to my 3rd function loader lines with quick connect when running the mower or a tree saw.

 

[Xfaxman]

Sounds good, but will your 3rd function loader lines pass 21 GPM?

And how will you handle the flow when you shut off the hydraulic motor and it becomes a pump due to the inertia of the spinning blades?

 

[Piston]

How much pressure will that 21gpm pump put out? If it's the one you referenced earlier at 2,000psi, then you can expect the equivalent of 24.5hp in a perfect world with no friction loss in your lines.

In comparison to your 32 hp at the pto, you'll be losing a LOT of power. Not to mention it's going to be hydraulic hp vs mechanical hp and you will notice a huge difference.

I'd LOVE to have a front mounted mower like that, but I wouldn't give up that kind of power for it. I've often thought a skidsteer would be a good investment for front mounted implements.

Unfortunately, your very limited with such a low PTO hp to begin with.

 

[truckinfouble]

I plan on a bypass like several others have put on their mowers that will let the fluid flow one way and the motor to slow down like normal. The lines will be 1/2" and should handle flow. Pressure will be set to 2500 and PTO output changed as of this morning to 6? HP due to upgrading machine to a 5570 Mahindra

 

[Piston]

I plan on a bypass like several others have put on their mowers that will let the fluid flow one way and the motor to slow down like normal. The lines will be 1/2" and should handle flow. Pressure will be set to 2500 and PTO output changed as of this morning to 6? HP due to upgrading machine to a 5570 Mahindra

NICE!!!! Way to step it up a notch! Well in that case you should be able to run a 3,000psi pump at more than 30gpm!?!? That you can do something with!

 

[Xfaxman]

I plan on a bypass like several others have put on their mowers that will let the fluid flow one way and the motor to slow down like normal. The lines will be 1/2" and should handle flow. Pressure will be set to 2500 and PTO output changed as of this morning to 6? HP due to upgrading machine to a 5570 Mahindra

Hydraulic brush hogs have an advantage over PTO brush hogs, in that the blades are sharpened on both sides so it can cut rotating in either direction. I use normal for grass and reverse rotation for heavy brush.

Ours uses 3/4" hoses and the motor has a cushion valve built in to bring it to a stop quickly from either direction.