Takeuchi 135 min-excavator thumb will just work in one direction. Changed the lines and it will work in the other direction. Can toggle the joystick switch up and down and you can here the solenoid cycle each time but will only operate in one direction. Did over power thumb with log held in thumb- hit boulder forcing jaw open -worked only in one direction after???? Diverter valve damage??? Thaks
Relief might be stuck open
Another possibility is that the piston has become detached from the piston rod - listen for a clunking noise at the cylinder when you operate the thumb. Kind regards Uffex
There should be a three way valve somewhere in the machine that provides two way from for the thumb and return to tank when shifted the other way. The return to tank flow is to run a hammer or compactor attachment. Also check to see if there are shut off valves on each side of the stick.
Close Valve #71
does your machine have a place to select between continuous flow and two way flow? could be set on hammer setting instead of shear or grapple setting. maybe it got bumped along the way.
Thanks for helping me to get my head out of my butt. Cant believe I forgot about the hammer valve! Yes I hit it and will be disconnecting it as we do timber thinning work and it will be hit again by a branch and confuse me again. Last year a branch hit the plastic radiator drain plug and the anti-freeze loss had me baffled till I got it back to my shop and could see the drip on the shop floor, was not obvious on forest floor. Keep over-thinking things lately, need to start with the basics before jumping to worst case possibilities. TOM
Most people just take the handle off the valve and store it in the cab until they need it.