I have a 1969 case 580ck that I have been trying to bring back from the grave for some time now. It was my dads tractor for many years, and in fact the tractor I learned to drive first, when I was about 12. Anyway I had three of the hoe rams off the tractor for rebuild, and I don't have the appropriate tools at my house to remove the rams. I took all three rams up to my dads shop, where I processed to rebuild them. When I got the large dipper ram apart, I realized I had the wrong seal kit. I placed the pieces back in my truck and headed home. I eventually got my hands on the correct kit, and was able to finish the rebuild. I was successfully able to to reinstall the rams on the hoe, but when I fired the tractor up to test my work, I realized I had done something very wrong, because the dipper ram would not actuate through its full range of travel. I decided to take one of the hydraulic lines off, just to verify I had good pressure. This is when I realize what had happened. When I brought the pieces back from my dads shop, I packed a hand towel in the ram so that I would not have hydraulic fluid all over the bed of my truck. Well when I came around to finishing the job, I forgot about the rag, and reassembled the ram with the rag still inside. Now I had forced the rag into the hydraulic system. I was able to blow most of the rag back out the hydraulic lines it was forced into, and I proceed to filter my new hydraulic fluid with paint mixing filters. I cycled the fluid through the same hose three times filtering and adding it back to the tractor. Everything seemed to be clearing up fairly well, so I reinstalled the hydraulic line, and added new fluid. I fired up the tractor and tried to actuate the hoe, and got now movement at all, so I moved to the loader valves and once again, no movement. My question is now where do I start, there is probably more than 100 feet of hydraulic line, low and high pressure, with several valves, and I'm just not sure where to begin.
Check the line feeding the pump. Sounds as though it is not getting any oil. Unless of course you can hear the motor load up when you run the levers. Worst case would be some of it went threw the pump. Should check and make sure that is turning.
I am getting enough return to fill the tank and run fluid at a fairly high rate back through the hydraulic line that I pushed the rag through, but as soon as I connect the line, I get little to no response out of the rams. I can hear the pump load up but I wonder. Is there a check valve in the pump that may be stuck open from part of the rag? Just grasping at straws.
I am not to familiar with the 580's. I don't know of a reason to put a check valve on the pump. There are however reliefs in the valve bodies. They should be a cartridge you can simply take out and clean the pieces out of them. I would hope you have checked the hyd filter it self also.
There is probably a suction screen in your tank that may be plugged too. You need to open up that cylinder and make sure there is nothing left in there too. I saw this same scenario on a 992 Cat loader and it was not cheap to fix.
The tank on a 580ck is part of the frame, i'm not sure how there would be a screen. Where would I look for it?
Does anyone know if the low pressure return has enough pressure to work something like this out eventually? I'm wondering if I ran the tractor for a while, if maybe the pieces left in the system, would slowly work there way out, and into the filter.
Any oil coming from any cyl. has to go through the spool in the control valve. I would think rag debris would have a hard time getting pass. Might pull a line from the cylinder in question at the valve and look. I don't believe there is a strainer on the suction side. The pump draws oil from the line coming from the control valve which is also tee'd into the tank supply.
Being it was a rag you may stand a chance it will work its way out. It is about the only choice you have short of taking every line,cylinder and valve body off and taking item apart to clean them and even then all it takes is one piece to screw things up again. If everything works now run the **** out of it. It will do it good and hopefully clean itself up. RZucker is right. If it was a machine that is making you a living this is a very elaborate fix.
Are all other functions working properly?
No. Rag debris will go through the spools, into the return, and if there is no suction screen right to the pump to be recirculated to the system, the return filter may catch some of it… 'til it goes to bypass. If this was a revenue machine it would be a catastrophe. I have cleaned out too many machines that had a component failure to say just "run it and let the filter catch it".
Well... this is not a revenue machine, but it drives me crazy when I do something so stupid. I have taken the control valve off and taken it mostly apart. It looks perfect. I just took the hydraulic pump off and apart (even though I could not think of a good reason why that gear pump would not just destroy any rag debris). No problem found, but since it's apart, I'm going to rebuild the pump. It looks really good for its age, but I figure it will start leaking after I broke all the seals. I think I have narrowed the problem down to somewhere in the return though. When I first power up the tractor, I get the pressure gage to jump up to about 600 psi for a second. The pump drains the tank down below the the suction level, and the pressure drops down to almost zero. The pump then makes the noise it usually makes if I'm low on fluid. I turn the tractor off let it sit for a second, check the fluid level and it is back up to full. All the lines are .5" or bigger, so I'm still not sure where to look next for the clog.