I would like to fab a thumb for my 3 ton X
My problem Is understanding where to put the relief valve
And also what kind of relief valve to use.
My machine already had a aux circuit with the relief valve built in. Perhaps yours is the same.
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When you say you would like to fab a thumb, I assume your machine already has an auxilliary circuit on the boom? Or are you going to have to add that as well?
On most machines like that, there are ports on the auxilliary control valve to install relief valves, they may just have port plugs installed in the ports which blocks the internal port to tank. If so, simply remove the port plugs and install proper relief valves, that's the easiest fix for your problem.
Our local and jap imported KX 41/61/72's have all had port reliefs fitted in the auxiliaries, 2500psi down from 3500 main. Put a gauge in one of the pipes and see what you've got.
2500psi for a thumb sounds about right, as long as the bucket will just push it back.
I just put a thumb on my Kubota 2010 model which was plumbed for auxiliary but it did not come with the relief valve fitted, strange IMO...
Panel adjustment would probably be for flow, not pressure, but I'm not sure on your model.
What model is yours?, I'll see if I can find a pic
Last edited by Harry Dart; 10-15-2010 at 10:57 PM. Reason: additon