Thumb issue

[r50max]

I installed a hydraulic thumb on my KX 161-3, it was plumbed for it with a rocker switch on the control stick. The thumb will close but not open. Any ideas?

 

[Midwest]

Sounds like it may be in "1-way" flow. 1-way flow would we used for running an attachment like a breaker, where as 2-way is needed to run your thumb.

I cannot remember on the older machines how you switch between the 2 modes, on the newer machines there is a valve under the hood to switch between modes. When you press the auxiliary button on the panel how many times are you pressing it? If memory serves me right the 1st mode is max flow for both ports (which would be 2-way flow for your thumb).

 

[r50max]

It's a 2008, I have seen the valve mentioned on other forums but can't find this valve on the hydraulic system. The procedure outlined in the operators manual doesn't seem to provide two way flow. The rocker switch or solenoid may be defective.

 

[Midwest]

I'm going strictly off of memory here but if I remember right you actually have to put it in 1-way mode going through the panel (3rd or 4th button press) and not a lever on the older ones. The 1st AUX mode after hitting the button once should be 2-way with max flow to both ports. You should be able to go through the panel and adjust your flow rates to each port, if you have your OM it should tell you how to check flow rates to each port.

I would check to see that you have flow going to both ports and someone didn't crank down the flow on the 1st AUX mode by mistake.