Hello, I'm a newb so I can use a lot of help! I recently bought a 580ck. Everything was working great, but then I noticed the swing while using my left pedal started to slow down and then had almost now pushing power. If I hit one of the bucket arm sticks while it was moving it would speed up ( I can't remember which stick it was), but now it will hardly move, if it will move at all, to the left. It swings perfectly fine to the right with full force, and all the other hydraulics work great. Is it the control valve seals? Where can I find a seal kit if that's the case. I've looked with no luck. Any other ideas on possible causes? Thank you!
If you try to move it to the left for a period of time, does the cylinder get very hot? If it does, I suspect the piston seals are gone inside the cylinder.
Check that it doesn't have any restrictions under the peddle .
Don't touch anything yet. With the engine OFF, and the backhoe secure on the ground with all pressure relieved so it doesn't squish you, take a good look at both swing linkages and spool valves. It helps massively that you have two so you can compare the one that works to the one that doesn't work. Obviously both pedals should operate the same distance, both valve spools should go up and down the same distance. Is there oil seepage on the bottom of the spool valve, maybe a little cap with a drop of fresh oil? that's general hydraulic 101, somebody will be along that knows that Case and knows exactly what the likely issue is, but you might as well understand this thing the hard way, right?
This is a simple problem, your spool is not stroking because of linkage wear or an obstruction keeping the pedals from going down, The reason another circuit makes it work is the spool to the other circuit shuts off the oil supply from open center and sends it to a cylinder circuit, whatever pressure increase the other system makes, the partially open swing spool allows flow to the swing cylinders, Remove the covers for the tower and adjust the pedals so they have a good upkick on the fronts, linkage wear allows the pedals to "flatten down" restricting how far the spool can open, lubricate the pedal shafts, they should be greaseable, There should be 3/8 NF turnbuckles on the connecting rods from the pedals to the rocker on the lever shaft, adjust them till desired swing pedal height is obtained. I have seen this multitudes of times, don't get into the hydraulic components till you follow this through.
New pins in the turn buckles will help. New turnbuckles and pins in all of the linkages would be even better.
Thank you all so much for the help. I'll definitely give these a try next weekend when I can get back to the backhoe! I'll keep you all posted on how it goes!
Just had to "modify" the foot pedal linkage on an old New Holland skidsteer at work because of non responsive function complaints..linkage was so worn out bucket functions were stiff and oddly enough, the tall/"large" guys were having a problem because the were cramped in the cockpit..those of us under 6 ft. really didn't have an issue...
I almost forgot ! Welcome to HEF, Calvin !!
Solved! Thank you for all your help. One of the link rods was bent and would just flex when the pedal was pushed down. I took it off straightened it and put some grease on the joints and she worked great!
Good job, I knew it was linkage related, A bent rod is a rare one but you found it.