So I'm trying to help my neighbor out with this tractor. he inherited it from his father in law. tractor was not running and the hydraulic pump was missing off it. honestly that's about all that is known.
some wiring repair and a new battery got it running. we installed a used (but known good) hydraulic pump, new filters and new fluid and fired it up. the tractor moves, power steering works, 3-point works and rear remotes work. however the loader was acting very erratic when you tried to raise it might go up or it might go down but would immediately stop and the hoses would jump and the motor would bog down. it acted like it was pressuring both sides of the cylinders at the same time.
long story short I rebuilt the loader control valve. I did find a blown O ring and the spool caps and detents were pretty rusty inside.
the spools moved freely and there was no scarring or anything, I installed all new O rings, new detent kits and new spool cap kits all bought from Kubota. everything went together without issue and I'm 99.9% confident I assembled everything correctly.
After reinstalling the control valve the loader is still not working correct. It has 2 different issues that I can identify.
1st when attempting to move the bucket in either direction the engine almost stalls and hear the pump like if it is dead headed and the bucket does not move at all, this issue was there before and after rebuild.
(when i loosen the lines at the cylinders only a little fluid comes out and the symptom is the same.)
2nd when trying to raise the boom if you pull back on the control lever 3\4 or less, the bucket will drop.
but if you pull it back all the way with mild force it will go up for a little ways then slow to a stop.
(if I loosen the opposite line on the cylinder the boom goes up normally)
I did not replace the relief valves on the loader control valve, they are a bit pricy and I'm not sure they would cause either issue.
I feel like I am missing something simple but I am at a loss, any help would be greatly appreciated.
some wiring repair and a new battery got it running. we installed a used (but known good) hydraulic pump, new filters and new fluid and fired it up. the tractor moves, power steering works, 3-point works and rear remotes work. however the loader was acting very erratic when you tried to raise it might go up or it might go down but would immediately stop and the hoses would jump and the motor would bog down. it acted like it was pressuring both sides of the cylinders at the same time.
long story short I rebuilt the loader control valve. I did find a blown O ring and the spool caps and detents were pretty rusty inside.
the spools moved freely and there was no scarring or anything, I installed all new O rings, new detent kits and new spool cap kits all bought from Kubota. everything went together without issue and I'm 99.9% confident I assembled everything correctly.
After reinstalling the control valve the loader is still not working correct. It has 2 different issues that I can identify.
1st when attempting to move the bucket in either direction the engine almost stalls and hear the pump like if it is dead headed and the bucket does not move at all, this issue was there before and after rebuild.
(when i loosen the lines at the cylinders only a little fluid comes out and the symptom is the same.)
2nd when trying to raise the boom if you pull back on the control lever 3\4 or less, the bucket will drop.
but if you pull it back all the way with mild force it will go up for a little ways then slow to a stop.
(if I loosen the opposite line on the cylinder the boom goes up normally)
I did not replace the relief valves on the loader control valve, they are a bit pricy and I'm not sure they would cause either issue.
I feel like I am missing something simple but I am at a loss, any help would be greatly appreciated.
