Bucket rolled backwards

   / Bucket rolled backwards #11  
That indicates one or both cylinders have failed.

Under extension there's nothing to control the transfer of fluid from one side of the gland to the other. So the bucket falls and creates vacuum within the cylinder barrel.

Under compression the fluid is put under pressure. The more weight/push you place on the cylinder the more it will collapse and create pressure thru the air that's been introduced thru the valve return to tank line.

I'd flip a coin and remove one cylinder and disassemble it for repair. If I didn't see obvious damage to the gland/rod, I'd disassemble and rebuild the other one. So, have two rebuild kits on hand. They aren't expensive.
 
   / Bucket rolled backwards #12  
Oh, I forgot to confirm, you did this test with the hoses uncoupled and all internal pressure released?
 
   / Bucket rolled backwards
  • Thread Starter
#13  
Yes, I did test without the lines connected. The bucket fell when lifting the arms.

What’s odd is hydraulic fluid came from the unconnected hoses as I lifted the arms? Is that normal? I didn’t go left/right to curl, just up/down.

I may try to tear one apart & see what’s up. Thanks for your help.
 
   / Bucket rolled backwards #14  
Just got home and the bucket doesn’t roll back flat willingly. If I have it flat and lift the main arms up the bucket uncurls.

If I put downward tension on the bucket, it will curl it back a little at a time as long as there’s downward pressure. Once I raise it up, the bucket falls again.

I’m baffled.
Good news! Maybe only one cylinder rod has separated from its piston. Whats happening is that the hyd fluid is acting on both cylinders under some pressure. Since one cylinder has a big hole in the piston where the rod used to be fastened, the hyd fluid goes right thru keeping the pressure very low. BUT that pressure acts on both cyls. On the good one it pushes on the piston annulus outside the area covered by the rod. - This gives a retraction force from that cyl. On the bad one the pressure acts on the end area of the separated rod, pushing it outward - but less than the inward force from the good cyl. The weight of the bucket is just too much to prevent the slight inward surplus from giving a weak net curl action.

- - But it might be I have incorrectly interpreted the actions and degrees of response you related and that both cyls might be bad. Its not possible to be sure without checking both cylinders. If the nut(s) have stripped off, the rod(s) may have to be replaced. Also you must check whether the cyl tubes themselves were swelled by the extreme fluid pressure caused by the forced extension.
 
   / Bucket rolled backwards #15  
Just got home and the bucket doesn稚 roll back flat willingly. If I have it flat and lift the main arms up the bucket uncurls.

If I put downward tension on the bucket, it will curl it back a little at a time as long as there痴 downward pressure. Once I raise it up, the bucket falls again.

I知 baffled.

And you will be until you tear the cylinders down.
 
   / Bucket rolled backwards
  • Thread Starter
#16  
Well I started taking the hoses off & noticed the left drains no oil so I pushed the rod up & oil shot out telling me it seemed to hold pressure.

I remembered the right cylinder draining out yesterday. So I left that one and went to the right. When I took it off I could hear something rattling.

The rod pulled straight out of the cylinder, threads were stripped.

Now the nut & packer is still in the cylinder with no idea how to fish out??? This keeps getting better & better. Heading to JD place to price cylinder & get options on what to do.

IMG_2531.jpg
 
   / Bucket rolled backwards #17  
Well I started taking the hoses off & noticed the left drains no oil so I pushed the rod up & oil shot out telling me it seemed to hold pressure.

I remembered the right cylinder draining out yesterday. So I left that one and went to the right. When I took it off I could hear something rattling.

The rod pulled straight out of the cylinder, threads were stripped.

Now the nut & packer is still in the cylinder with no idea how to fish out??? This keeps getting better & better. Heading to JD place to price cylinder & get options on what to do.

View attachment 636507
Check the diameter of the cyls near the base and then again about 6 inches from the rod end. If theyre not ballooned see if you can just replace the rods. . . . From the pic of the threads it looks as tho the nut may have loosened and screwed part way off over time before final rip off. :confused3:
 
   / Bucket rolled backwards #18  
If the gland hasn't turned sideways in the barrel, which it can't unless it exploded, apply air to the barrel end and see if the gland will slide out? If not, you'll have to build a "hook" of some kind to fish it out.
 
   / Bucket rolled backwards #19  
Take the gland off and smack the open end of the barrel on a wooden block with the base end straight up. The piston will slide to the open end.
 
   / Bucket rolled backwards #20  
I had something like this, use a 1/4" threaded rod with a nut, then washer and finally a nut to tighten down the washer. That will go through/past the piston. Use the edge of the washer to catch the backside of the piston and put pressure on the edge to pull the piston out.
 

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