Hello, I have a cat 235c excavator that I am adding a hydraulic thumb thumb to. I have the thumb and all its appurtenances ready to install, so yhat part is fairly self explanatory. Where I’m struggling is in figuring out how to provide hydraulic control and supply to the thumb cylinder. My excavator does not have an auxiliary hydraulic control valve on it from the factory. One option I’m considering is to add an auxiliary gear pump to the engine accessory drive, and use the flow from this pump to operate the thumb, via an electric solenoid controlled valve. Has anyone had experience adding a thumb to a 235 cat excavator? Any insights would be greatly appreciated! Thank you
Meanwhile, you could search the HEF archives. We’ve discussed this a few times before.
I’ve made searches of HEF for this info but haven’t had much luck… I’m probably not doing the right kind of search
First thing is post up the serial number.
Google works about the best for locating older threads on the HEF.
Kind of what I have noticed as well...
Try using a google search formatted like: site:HeavyEquipmentForums "235" "thumb"