Hello Everyone, I have a 1970 Case 580Ck that has an extendahoe option on it. The dipper cylinder control will pull forward to bring it in but you cannot push the control forward to push the dipper arm out. I’m thinking something is locking the spool valve up partially. Am I correct in thinking some dirt or seal is blocking the valve? How would I get started on fixing this? I’m hoping I can take apart the one valve that is affected instead of taking the whole block out. I’m hoping to do this soon so I can get the machine all back together. You can see the rod is bent from someone other than me trying to force it with no avail. I have the backhoe off but need to get the machine back together soon. Any help is greatly appreciated.
From what I can see in the service manual for my backhoe with a similar valve, (I have the model 26 backhoe with a Commercial Shearing C20-20 valve), you will need to remove the whole valve assembly to do any work on it. There are long bolts that run across horizontally that keep the whole sandwich squeezed together. See these pages from my service manual. I can send you the PDFs of the whole manual if you're interested.
I'll take a piece of boom cylinder packing lodged in the control spool for $1000.00 Alex
Remove the spool if you can while the control valve is on the machine. You will be able to see if it is damaged or the bore of the section it is in is damaged. If you have to take the valve apart to replace that section it will expensive. Replacing the entire control valve may be a better option depending on what it will require to repair the one you have now. Those "O" rings are stupid expensive to replace.
Thank you for the info and the diagram, it’s very helpful. Confirms what I was worried about. I was hoping I could drop out the spool from just problem valve instead of removing the whole assembly
Lol, that’s my thought too, be interesting to confirm it. Hoping to take it apart Tomorrow.
Thank you, yea I was hoping to remove the spool while the control Valve is in the machine but I’m thinking it might be held together as Abseim said above. I’ll be messing with it in the morning and hopefully report back