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KX080-4 thumb control

mudnducs

Well-Known Member
Joined
May 14, 2014
Messages
63
Location
Jonesborough, Tennessee
Occupation
retired mech eng
Rookie question:

Got a used Kubota a few weeks ago. Out this morning clearing trees and brush I went to close the thumb and it had quit working. Got off to take a look and the hose had come uncoupled at the quick release (dont know how).

I'm trying to reconnect the hose but I cant get the external sleeve to slide back. I'm wary that this may be because there is still pressure in the aux circuit that controls the thumb. Operators manual says to shut engine down with all hydraulic loads on the ground then turn the key back on to the run position and operate the controls.....that should dump all pressure back to tank.

Did that....external sleeve is still stuck. Tap it with a punch and ball peen (staying out of the way)?
 

T320FL

Well-Known Member
Joined
Sep 16, 2015
Messages
54
Location
FLA
Don't hammer on anything yet. After you sat in the seat and turned the key to the first click did you lower the safety lever on your left? Did you press the aux. button to activate the thumb? Then move the rocker button for the thumb. You should notice the boom "relax" when pressure is let off.
 

T320FL

Well-Known Member
Joined
Sep 16, 2015
Messages
54
Location
FLA
I should have said the boom will "relax" when you push the joysticks forward.
 

mudnducs

Well-Known Member
Joined
May 14, 2014
Messages
63
Location
Jonesborough, Tennessee
Occupation
retired mech eng
FIRST: Thank you so much for the response to rookie questions T320FL! :)

Ive done the drill twice and see nothing 'relax' once the boom and arm are extended and bucket is on the ground.
Aux flow display screen says everything is set to full flow (no restriction) and cycling the key on/off, with the controls both locked and unlocked, shows no difference.
There is a small detent ball on the side of the coupling that keeps me from sliding the sleeve back....can those detent balls get stuck?
 

phil314

Senior Member
Joined
Dec 28, 2014
Messages
356
Location
Otsego, Mn
Occupation
Instigator of Choas
if you are talking a coupler like this, there is a slot that needs to line up with the detent ball.
Twist the outside ring till they line up, then push back.
Hope it's that easy.

12-Flat-Face-Female-Coupler-ISO.jpg
 

mudnducs

Well-Known Member
Joined
May 14, 2014
Messages
63
Location
Jonesborough, Tennessee
Occupation
retired mech eng
Yes.. like that. Dixon 4HTF6-5000. So far I cant budge it. None of the pressure relieving instructions in the operators manual seem to work. I may just slowly unscrew the coupling to bleed off pressure.
Thanks for the input assist gents. <thumbsup>
 

mudnducs

Well-Known Member
Joined
May 14, 2014
Messages
63
Location
Jonesborough, Tennessee
Occupation
retired mech eng
Got it. Wound up having the bleed off pressure from the cylinder and from the pump. Must be getting old and weak.
Thanks for the input gents.
 
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