Hydraulic cylinder bad?

I assume that the hydraulic fluid should have (since it was sealed on both ends) held the bucket in place. True?

Assuming I have a bad cylinder anything I need to know before I replace it? Specifications other than the physical dimensions matter?

Glad you found the problem. You should be able to get replacement seals for it OK. If they are the V-ring packing style you may want to try using a piston ring compressor to facilitate installing the piston back into the cylinder.

You should try to get as much air out as possible after installing. I was once told that the air will work out eventually...but my own experience does not support that. I replaced the seals on two bucket cylinders a couple of years ago and still have noticeable air in the system. One day I am going to start cracking the swivel joints at the cylinders to try to get more of the air out. I suspect that will be somewhat messy and is why I have been avoiding doing it.

Rod

Lead. It's a worth endeavor. Again, thank you.

It sounds to me like the piston seals are shot. That would allow oil to leak past the piston from the rod end side to the other side, thereby permitting the cylinder to extend from the weight of the bucket.

I would think that you could replace the piston seals. Should be a lot cheaper than buying a whole new cylinder. Piston seals on double acting cylinders are usually just a pair of v-ring packing sets facing in opposite directions. This type of seal should be readily available at any source of hydraulic equipment supplies.

Rod