Why are both of my swing cylinders extending when I try to swing either left or right

[4500hoe]

This is on a Ford 4500 T/L/Backhoe

[MikeInEburg]

Something is plumbed incorrectly. When swinging, one cylinder should extend and the other retract. Is it possible that hose connections were changed?

[J_J]

Are you saying that the BH can't swing now as both cyl are extending?

What was the last fix you did to the BH?

Did you loan it out to someone?

Did you put a gage on either or both cyl?

[muddstopper]

If nothing has changed in the plumbing, One cylinder could be bad allowing the oil to bypass internally.

[hank193]

This is on a Ford 4500 T/L/Backhoe

I've owned a couple of the good old Ford 4500 rigs and they do things a little different on the swing system hydraulics. Both swing cylinders are set up to PULL on the end of chain that fits around the base of the swing pin.They are single acting cylinders with two hoses going to each one. One hose connects to the swing valve and feeds pressure to PULL [or retract ] Now the other smaller hose connects BOTH cylinders together . Ford didn't just put a vent on each like other peoples SINGLE acting cylinders , NO . So what happens is the cylinder get worn and start passing oil to each other. Usually the little hose breaks or leaks enough so things keep swinging. Disconnect the small hose and get ready to catch some oil as you operate ...or remove and rebuild [probably both } cylinders. You can sit down the bucket, set down the outriggers and block up under the backhoe, disconnect the big nuts on each side of the seat . Use the outriggers and down pressure on the boom to lift the hoe up a little off the lower pins . CAREFULLY and slowly drive forward while watching the tractor to backhoe hoses . Stop before you break a hose and you should have room to remove the swing cylinders from the chain and rebuild them. A shop manual can probably be found on ebay and explain it better. Sorry for such a long post. Be careful, its all heavy !!!