I just picked up a case 590sl with a front hydraulic tool coupler. I have greased the pins. Are they supposed to retract at the same time? I can get one side to retract, however the other just moves a small amount in and it seems to wait until the other side is completely pulled in before moving. Also do these retract even if the bucket is not perfectly flat or is there to much friction on the pins ? Seems like the cylinder is weak, however not leaking fluid. What are these cylinders called "push pull" ? trying to see if maybe the seals are worn as the whole cylinder area was full of rocks, crap and dirt. I can't find any sources that describe how these are supposed to operate. Hoping one of you can describe a properly working one. Hoping it's not some type of worn spool issue. Mike
Most will engage close to the same time, keep them lubed. I have several machines with the couplers and stress to the operators to have the attachment off the ground a few inches when locking and unlocking to keep the wear down and allow smooth hookup. You still have to do a little shake now and then to get them to hook or unhook. If you are locking and unlocking within seconds your ok. Some are full hyd and some have a spring that pushes the lock pins out when hyd pressure is released.
These must be spring loaded as only two hydro lines. Lines are pretty small in diameter. Might try and remove cylinder and have rebuilt, however if not leaking through the seals would that be a reason for inability to overcome friction? They do move without loads on them.