Bradco 11MD2 what's the hydraulic pressure requirements

[ThunderFarm]

I have a Kubota M5700. I also have a Bradco 11MD2 3 point hitch attached backhoe unit. Everything works well with it except the main boom. I can't seem to get it to pick up the main boom unless I'm helping lift it. I'm wondering if it's a lack of hydraulic pressure from my tractor. The type of hydraulic control I have is a handle I have to wedge in the up position to get the hydraulics flowing. I don't know what my tractor produces and I can't seem to find any specs online for the backhoe. I'm not sure what to do from here so any help would be appreciated.

Tony

 

[rScotty]

Our Kubota is a similar size.

Most open center hydraulic systems in tractors made in the last 20 years run about the same max pressure - 2700 to 3000 psi. Anything over 2000 psi will lift that boom just fine.

No open center system will develop more pressure than it has to have to move a cylinder. Only when the cylinder is fully restrained will pressure build to max. And then what happens is a relief valve opens. Of course if the problem is a stuck relief valve in the BH valve set then the cylinder would not move either,...

I have pressure gauges permanently plumbed into one tractor - you may want to do that, it is inexpensive to do. But you do have to know what threads you want on the fittings and then order some parts.

The upside is then you will know a lot more before spending serious money on mechanics, hydrauic pumps, and valves. Or for a few hundred bucks you can buy a complete hydraulic test kit from Amazon and we can figure it out here on TBN.
Luck.
rScotty

 

[joecdeere]

this is out of my 11HD manual, I'm sure the MD is about the same

 

[Sportsman762]

I have a Bradco 11MD and run it off of the rear remotes without an issue. It's valve is set at 2,250 psi, and needs 8-12 gallons per minute. The Kubota M5700 has a 11 GPM system that I would assume is at 2,500 PSI.

I run my Bradco 11MD off of a remote as well and find it works great at 10 GPM.

Page 131 on has trouble shooting for the Bradco MD2 series hoes.

https://forddistributing.com/media/amasty/amfile/attach/OM360_Bradco_315_MD2_Backhoe.pdf

Below is the parts manuals for the MD2 series

https://forddistributing.com/media/amasty/amfile/attach/m/d/md2_series_backhoe_parts_manual.pdf

I have had to rebuild all the cylinders on mine and some other repairs due to age. Its a good backhoe attachment.

I would encourage you to read on the forum the hazards of 3 point backhoes and their tendency to cause damage to tractors. I built a subframe for mine as the 11MD is a darned big hoe for the back of a tractor and can easily damage it. It is not hard to find stories on here (with photos for proof) of a 3 point backhoe causing a tractor to snap in half at the bell housing, or break a mounting ear off of the 3 point on the tractor side. The M5700 is a nice tractor but is light for the size. I have spent a fair bit on a M6800 and loved it. A M9000 is a dream tractor for me (or a Versatile 276)

Keep us posted on your repair.