B2630 loader bucket hydraulics issue

[alaskatgc]

My tractor is a B2630, loader LA403, total package has 130 hours. Two weeks ago while moving snow, I dumped a load in the ditch and that was it. The bucket was in full dump and no curl function was there. Moving the lever into curl position produced no movement in the bucket. If I held the lever in curl position and dragged the bucket backwards, it would come back to horizontal (while on the ground), but as soon as I raised the boom, the bucket would just dangle loosely. It remained freely dangling until I moved the lever to dump and the hydraulics would then catch the bucket and force it to full dump, per normal dump operation.

I took the bucket operating valve apart this past weekend and everything is clean as a whistle and the check valve has full contact all around (based on the shiney wear circle). I saw no issues in the valve at all. I now suspect one of the hydraulic cylinders has failed, although I don't know enough about them to know if a cylinder can fail in one direction only. I intend to isolate one at time, using plugs in the two supply lines feeding each cylinder.

Does anybody have any thoughts and/or suggestions to offer?

Tom Carson
B2630 TLB
Juneau, Alaska

 

[nspec]

I've got the same machine as yours. I've noticed on mine, when I dump, there is a second detent in the dump position. If I mistakenly push the lever all the way (lever feels like it does when you would go to float), the bucket dumps fine, but will hesitate when curling back up, starting off slowly at first then regaining normal speed. It always comes back fine, however - haven't had it lose function totally like yours. I've just learned to be careful and not push the lever so far. Not really sure why it is like this. Book does show a second position for the dump function.

 

[dodge man]

Just a thought on how to diagnose the problem. Try switching some of the lines around. Say swap the hoses that raise and lower the boom to the curl and dump ports. Then if you still have the same problem, that might isolate it to the cylinder. Also make sure the hoses are hooked up well. They can look like they are hooked up, but not be.

 

[kennyd]

I've got the same machine as yours. I've noticed on mine, when I dump, there is a second detent in the dump position. If I mistakenly push the lever all the way (lever feels like it does when you would go to float), the bucket dumps fine, but will hesitate when curling back up, starting off slowly at first then regaining normal speed. It always comes back fine, however - haven't had it lose function totally like yours. I've just learned to be careful and not push the lever so far. Not really sure why it is like this. Book does show a second position for the dump function.

It's called a "regenerative" function. Do a search for the term "regen" and you will read more than you want to know

 

[kobyp]

Just a thought on how to diagnose the problem. Try switching some of the lines around. Say swap the hoses that raise and lower the boom to the curl and dump ports. Then if you still have the same problem, that might isolate it to the cylinder. Also make sure the hoses are hooked up well. They can look like they are hooked up, but not be.

Start with this....