Converting John Deere 7 backhoe to 3 point

[Greygoose]

Hi All-
Have a 254II Lenar 4X4 and just got a good deal on a John Deere 7 backhoe that needs a little work and was wondering if anyone ever converted one of these to a 3 point setup.It looks like all I would have to do is cut off the long frame mount legs and drill them for pins to hook up to the lower lifting arms of my 3 point,then just use the correct length top link? I checked the weight and the 7 is actually lighter (800lbs?) than other 3 point backhoe attachments,so I think I should be ok there.
Mike

 

[kennyd]

Why not make the subframe fit your machine? You will have a MUCH stronger setup and you won't risk breaking your tractor. It's not just the weight of the backhoe, it's the forces it imposes when your digging that will cause problems.

 

[Greygoose]

First off I don't have the subframe,only the 2 small pieces for the very front of the legs came with it.Also,I am only going to be doing very light duty work maybe once a month with it.And unless I can figure out the hydraulics,I may sell it as is.Is there supposed to be a return line on these?I only have one quick connect,but right above that fitting on the valve body,there is a line missing-just an empty threaded hole that leaks some oil when the unit is moved.Thanks again,
Mike

 

[kennyd]

First off I don't have the subframe,only the 2 small pieces for the very front of the legs came with it.Also,I am only going to be doing very light duty work maybe once a month with it.And unless I can figure out the hydraulics,I may sell it as is.Is there supposed to be a return line on these?I only have one quick connect,but right above that fitting on the valve body,there is a line missing-just an empty threaded hole that leaks some oil when the unit is moved.Thanks again,
Mike

You need two lines to run the backhoe, one is the feed and the other is the return-to-tank line. Backhoes are usually powered by what is called the "Power Beyond" lines on the tractor. I assume you have a FEL on your tractor? If so, then how many hoses are connected to the valve?

 

[Greygoose]

Thanks Kenny-
I have one high pressure feed line at the back of my tractor with the quick connect fitting to hook into the in line.I have no return fitting on the tractor though.I did find on the backhoe valve body the return line fitting right above the in fitting (it says "out").It is missing the line along with a couple of others that were robbed off the backhoe by the previous owner.My front end loader has a total of 7 fitting holes-5 are used for the loader hooked up and 2 just have threaded plugs in them.Thanks again very much,
Mike

 

[kennyd]

OK, 5 makes no sense...You have 4 from the work ports to the bucket cylinders, then you have 1 FEED connected to the IN port from the pump. Then you will have 1 or 2 more...for a total of 6 or 7.

Can you post pictures of your machine, with close ups of the valve?

 

[Greygoose]

Your are right Ken-sorry.There are a total of 6 lines running into the front end loader valve.
Mike

 

[kennyd]

OK, so since you have only 6 hoses, you do NOT have the common "Power Beyond" setup in use.

Now bear with me, I have questions...

Are any of the ports labeled on that valve? If so, is there one marked PB or BYD?
Who in the maker of it?
What is the GPM and PSI rating for your machine?

 

[kennyd]

Thanks Kenny-
I have one high pressure feed line at the back of my tractor with the quick connect fitting to hook into the in line.I have no return fitting on the tractor though.

How does this line get activated? You can't have a high pressure line and no return...the PRV (pressure relief valve) will always be active and the fluid would overheat, or the pump would grenade itself. Post more pictures.

 

[Greygoose]

On the rear of the tractor is a quick connect fitting.If you can look at this manual on page 20,maybe you can make sense of it for me.I did find the optional return tapped hole.Thanks again.
http://www.mahindrafrance.com/mahindra254.pdf