• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

thumb only works in one direction

matava

New Member
Joined
Jul 27, 2019
Messages
2
Location
california
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
 

uffex

Senior Member
Joined
Jan 23, 2012
Messages
4,464
Location
Lincoln UK
Occupation
Admin
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
 

John C.

Senior Member
Joined
Jun 11, 2007
Messages
12,865
Location
Northwest
Occupation
Machinery & Equipment Appraiser
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.
 

farmerlund

Senior Member
Joined
Nov 22, 2014
Messages
1,237
Location
North Dakota
Occupation
Farmer/ excavator
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.
 

matava

New Member
Joined
Jul 27, 2019
Messages
2
Location
california
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
 

John C.

Senior Member
Joined
Jun 11, 2007
Messages
12,865
Location
Northwest
Occupation
Machinery & Equipment Appraiser
Most people just take the handle off the valve and store it in the cab until they need it.
 
Top