I bought a 1987 case 580k and have been using it for about a year. Was on a hill working with the bucket when all of the hydraulics stopped working. Bucket, steering, hoe, stabilizers... nothing would move. Opened the hood and the serpentine belt was shredded. Engine will start and run. I have a new belt on the way but I thought the hydraulics should still work without the serpentine since the pump is driven off of the engine crank (yes, I know that would not a good idea . Fast forward 2 days later I noticed the extenda-hoe had drifted down which has never happened. Any thoughts are very much appreciated!
Welcome to HEF, Caper58 ! The hydraulic pump drive is probably broken. It is on the front of the engine crankshaft. You need to use the tractor serial number to get the correct parts. There are different model's of the 580K's.
Update... Well I'm back up running and here's what happened which might help somebody else. First I checked the hydraulic oil level which looked about right but since I was on a hill side I overfilled it just to see and everything started working. Then it was time to get the backhoe off the hill and back to my shop. Once at the shop, I lowered the hydraulic oil to the correct level and cleaned that dirty sight glass I've been treating to do for a while Next it was time to the replace that destroyed serpentine belt. I've found a lot of post about how to take off the front counterweights along with various other front end parts but when I came across someone talking about just loosening the hydraulic pump coupler, sliding it forward on the pump spines where you get just enough space to work in a serpentine belt, I decided to give that a try first. The sliding of the coupler went pretty well. I did modify a box end wrench with a long weird looking handle from an old tire iron, this made getting the coupler bolts loose in that tight space a lot easier. Slipped the coupler forward, belt went in, loosely started all of the bolts (needle nose pliers worked well for that), then tightened all bolts to torque standards with that weird handy-dandy wrench and I was done in less then 2 hours. So if someone needs to replace a serpentine belt, I think slipping the coupler forward might be worth a try. Hope this helps!
It must have been an awful steep hill to cause the hydraulics to stop working. Were you able to check the condition of the splines when you had the coupler separated?
I like to use moly grease on splines like that. I've seen some places say to leave them dry so they don't collect dust which is worse than dry. But if it sits more than runs, I figure the rust is worse than the dusty grease.
The hill was steep. I was cutting a switch-back when I slid off my cut... so I was using the bucket as drag anchor to get the hoe to a lower landing.... then the hydraulics stopped. It's a scary feeling with no functioning out riggers, steering, hoe or bucket. I let the out riggers drift down until one caught, then I chalked the tires before walking down to the truck and looking for some alcohol to drink What part of the splines I could see looked great but I was sliding the wrong way to see the splines the coupler sits on. It did slide easily and I could not get any coupler rattle with the bolts out before I slide it. I sprayed the splines with a grease I use on my boat trailer. It's hard to get off the trailer so I figured it might stay on the splines for a while.