Hello guys My Case 580 SuperE seems to have a problem with the hydraulics on the rear boom? Here's what it's doing. If the dipper is extended and out to the left or right it will swing back like it is just on a pivot? I need to keep the pedal down to hold the boom in one position. Then today I noticed while I'm maintaing the boom position with the pedal then operate the dipper or bucket I lose pedal pressure and the boom will swing freely again???? Sorry for all the improper terms I'm pretty green at this.
hyd's Bumping you up to the top. Surely 1 of these gentleman will have an angle of attack. I'm much green myself but I'll venture a guess. You have a valve holding open and pressure (holding the pedal) is the only way to keep a position. A burred up valve or maybe a worn or missing o-ring could be the culprit. As where to start looking, I have a service manual but haven't got to that part yet. I'd start at the control's and move on to the pump next. Surely someone more versed will chime in. Phil or Emach have much experince, at least as far as I've read so far. Sorry I can't help- more Chris
Thanks Chris Do you know,, can I service the valve with it installed? Scott
Check the caps for each one of the spools on the backhoe valve. Sounds to me like one could be loose. Possibly the swing spool. When this occurs it lets the spool shift. Therefore it is no longer centered within the valve.Everytime you activate a function you will cause the one that is loose to function also. They are located on the bottom of the valve.
I would say it is passing more oil thru one side of an O-ring.. Essentially one piston is stronger than the other if one of the two pistons is leaking. Also check the linkage adjustment for the two pedals also. Make sure both pedals are set exactly on neutral when at rest. Both pedals need to work exactly opposite of each other for them to work perfectly.
Thanks guys for the input. Last night I was going over the machine again trying to figure out how to get the valve apart, I had removed the pin from one of the swing cylinders and then I noticed that I could with very little effort make the boom swing? I tried this with the other piston as well with the same result. I was wondering then does this confirm that there is a internal leak in the control valve? Scott
Ok I found out what was wrong today. When I was taking apart the swing cylinder so I could get to the valve, I found that the mount (upper was totaly broke off) and the lower pin was cracked. While the cylinder was at the shop getting welded the welder thought the problem could be the cylinder seals could be blown. I tried to blow air through the cylinder that was repaired and it seemed tight. When Itreid the one on the hoe it passed trough like there was nothing in between. I guess that explains why the one good cylinder was so badly damaged and the loss of control of the boom swing! Thought I would let you guys know. Ottawa