Kubota LA403 bucket boom won't raise

[dmmj01]

Help!
My 2010 LA403 bucket boom won't raise. The bucket curl works in both directions and the boom will lower (even lifting the front wheels off the ground), but the boom will only raise to an inch or two off the ground. I thought it might be a leaking hose on the left boom lift cylinder, but I replaced it and the boom worked fine for one cycle, then quit working.

I bled the intake and outtake hydraulic hoses, plenty of fluid and no air bubbles. The hydraulic level is fine. But still no luck.

Any suggestions?

 

[pmsmechanic]

Sure sounds like one of your boom hoses isn't plugged in properly so check that. If that's ok then switch the hoses around and put the boom on the bucket curl outlets and the bucket outlets onto the boom outlets. If the problem stays the same them the issue is with the loader and if the problem switches to the bucket cylinders then the issue is with the valve. If the problem is with the loader then check to see if the piston inside of one of the cylinders has come off or is otherwise damaged. That's all I can think of off hand.

 

[J_J]

Reset the QD's.

 

[dieselcrawler]

I agree with check the quick disconnects... about a month ago my buddy thought his L4310 was FUBAR when the curl cyl did the same thing. Turned out one line had just slightly released from the QD enough to stop fluid flow.

Good luck... hope thats all it is.

 

[dmmj01]

When I switched the hoses, the problem did move to the bucket cylinders. Looks like the problem is with the valve. Or the boom hose?

Thanks - this helped a lot. At least I dont have to worry about the cylinders (yet).

Most grateful - Mike