Who has worked with a JD Backhoe

[philgreen]

I bought a JD855 with a #7 BH a few years ago. I immediately took the BH off and have just recently put it back on for a project. I have very little experience with a BH, but am impressed with my little #7. It seems to work good, but I have a few questions that more experienced operators might be able to answer.

The #7 has two multifunction valves, one for boom right/left as well as boom up/down, the other for stick up/down and bucket control. What I noticed is the controls seem to have very little capability to multi-function like the bigger more modern units do. For example, I can't really extend the boom and move right or left. If I try it, the BH might do the right or left move first then do the boom move, but not both. Sometimes, if I move the control just right I can get the bucket to extend while the stick moves, but this might be because they are on the same valve. What this ends up meaning is that I'm not as fast or as smooth as I'd like to be.

Is this normal or do I have a control problem? Anybody with good experience on the 7 or 7A BH have a comment?

Thanks,
Phil

 

[Cocre]

That's about how my 2006 3320 with a 447 hoe operates. Not but so much 8 gpm can do.

 

[Gale Hawkins]

I see that same thing with our 1983 JD 310B backhoe. I am learning what operations can be done at the same time but just getting started so I do not have specifics in my head.

I think that is normal and the 310 has a 30 gallon pump.

 

[kenstrac]

Your backhoe is an open system,commercial backhoes are a closed system and can operate all the functions at once.

 

[Gale Hawkins]

kenstrac I was told last week the inverse is true?

 

[Rob-D]

I thought it was an open system too. My JD BH works only one direction at a time also.

 

[Cocre]

On my open center system when the valves are feathered the flow will go to the cylinder with the least resistance, so sometimes you can boom and swing or whatever and whatever when the resistance is near equal. That is just the way it is.

I would think on an open center system when the control valve is fully off center then all the fluid is sent down that line. You would have to feather the flow to get fluid beyond the first open valve. I think.

 

[kenstrac]

kenstrac I was told last week the inverse is true?

The smaller JD tractors are open systems 1 function at a time.
Larger JD tractors have a closed system and can run many functions at a time.

 

[Gale Hawkins]

The smaller JD tractors are open systems 1 function at a time.
Larger JD tractors have a closed system and can run many functions at a time.

Thanks for clearing that up for me.

 

[Gizmo2]

Phil,
I have logged many many hours on a 1988 JD650 using the #7 BH and I can tell you two things. One, I wish my new 2320 had the #7 instead of the #46. Two, I could absolutely perform two movements at once. I surely miss the "L" shaped control levers on the #7 and I am seriously thinking about buying a set and putting them on the #46.