843 - weak bucket curl (roll back) roll forward is fine

[japmaple]

I have a 1985 843 serial 5026-M-21359. The bucket curl has been getting slower and finally stopped on Saturday. But it started working slowly again after it sat and leaked back to the level position. I have been checking out service manual page 2-1 and it says to check the unloading spool. The unloading spool is listed as being in the bucket positioning valve which is loaded in the right rear corner of the engine bay. Anyone have any experience with this issue? Any additional troubleshooting that is recommended before taking out the valve for inspection/service? The rest of the hydraulics seem fine, lift arms are fine, drive speed is fine. Tilt down (roll forward) seems to be fine. Only tilt up of the bucket (roll back) seems to have an issue. Thanks in advance for any ideas.

 

[Tazza]

When you curl, does the engine bog down at all?
I guess it could be the control block, but i'm not sure what could be causing it.

 

[Lowe.Buuck]

When you curl, does the engine bog down at all?
I guess it could be the control block, but i'm not sure what could be causing it.

Since that loader has a single hydraulic cylinder controlling curl, I wonder if the nut holding cylinder piston to the rod has loosened up.
It seems that I recall reading that the cylinder can continue to operate almost normally in one direction and hardly at all in the other direction.
Just a thought...

 

[farmshop]

Since that loader has a single hydraulic cylinder controlling curl, I wonder if the nut holding cylinder piston to the rod has loosened up.
It seems that I recall reading that the cylinder can continue to operate almost normally in one direction and hardly at all in the other direction.
Just a thought...

Does the bucket stay where you leave it or does it creep down? Have you looked at the linkage is everything moving as it should?