I'm finally hoping to start taking the rotary swing cylinder off the backhoe on my 931B. To remove the top cover off the rotary actuator it says to use 2 Cat ID4608 bolts that thread into the cover to push it off. Can someone tell me what size of bolts these are? I'm guessing 3/4" but not sure.
Yes. 3/4 unc.
Thanks Cmark! The serial number of my 1986 931B is 25Y1916. The backhoe is a 5G2150 but I don't remember the serial number, 22xx something if I recall. It came from the factory with the hoe and has the optional piston pump for the hoe. What's odd is that it also has a 4 in 1 bucket but only the 3F/1R transmission. Nige sent me the R&R manual for it a while ago. It looks like it's mostly just leaking out the top cover where the shaft goes through. It still works fine to swing so I was hoping to just replace the seals where the shaft goes through the cover and the big O-ring on barrel without taking the whole thing apart. I know the O-ring and 1 of the seals is available but not sure about the other seal for the shaft. Hopefully if the original type seal isn't available there will be a better replacement. I'd hate to take it all apart and not be able to find all the right seals I need. It would be really nice if I could find someone who has worked on these rotary cylinders before. Most of the bolts call for 350-375 ft./lbs. torque so I figure to just get them as tight as I can with about 2' of leverage.