JD 4600 w/460 loader bucket tilt problem

[Hound Dog]

I understand the unequal movement of the bucket cylinders but today the slower cylinder (left) totally extended out while the other one moves fine. Left the 50*F shop into 2*f temps and did some back dragging to clear a little snow. Then switched to bale spears, lifted a large bale, moved it closer to the gate, lifted it up high and dropped it. Trying to loosen up some ice on the bale. Then attempted to lift the bale again and the spears would barely move from the full down position. Tried full throttle but did little help. Took the bale spear off and the left cylinder went full extended to dump position while the right one would move okay. I was able to move the left cylinder by hand but it would return to extended position. Tried to attach bucket but no way to move that cylinder.
The dumping of the bucket has been slow to dump for a long time. Sometimes it will just stop but moving the lever in the cab would then dump okay.
Any ideas?

 

[beenthere]

Replace the bolt that keeps the right/left cylinders in correct timing. May be broken bolt.
Also, sounds like you are not using the regen dump feature properly.
Or re-set the quick hydraulic hose couplers. Sounds like one may not be properly connected.
Those are just three guesses I have to offer.

 

[Leejohn]

Sounds like the piston seals are bad on the left cyl.

 

[Hound Dog]

Sounds like the piston seals are bad on the left cyl.

I'm thinking the same thing as one shouldn't be able to move the cylinder by hand.
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Later with the tractor off I pullled up the left side and the right cylinder moved in the opposite direction. When I moved the right cylinder, the left one moved in the opposite direction.

 

[oldnslo]

Hound dog
Are you stating the two curl cylinders are operating independent of each other? I. E. The left stays extended and right strokes in and out?

 

[Hound Dog]

More info. At first the bale spears would not return from 'full dump' except at full throttle but would then drop down on their own. I heard a loud 'crack' noise and that's where I believe the roll pin on the torsion bar between the two sides broke. Then the left cylinder went full 'down' or extended but the right cylinder would move with the lever. I did replace the roll pin with a bolt, started the tractor and again it won't pull the cylinders to the up position and I believe if I forced it at high throttle it will break that bolt.

 

[Hound Dog]

yes.

Hound dog
Are you stating the two curl cylinders are operating independent of each other? I. E. The left stays extended and right strokes in and out?

Yes, with the torsion bar roll pin broken.

 

[oldnslo]

Something is strange if one cylinder will operate and the other does not since they should be plumbed in parallel. Both rod ends connected to each other and both blind or cap ends connected to each other.

Some thing breaking bolts sounds like something is bent and binding or flow between the cylinders is blocked.

 

[Hound Dog]

Could it be in the valve assembly?

 

[kennyd]

Could it be in the valve assembly?

No.

I'm betting bad piston seals as mentioned above.

Rebuilt both cylinders, replace the broken shear pins, then tractor on