Hydraulic Lock

Ron Fischer

New member

Equipment
L4740 HST (4x4), KX91
May 26, 2014
1
0
0
Salem, Oregon USA
I have a Kubota L4740 HST (4x4) with 910 hours of zero down time and regular maintenance. This machine has had a privileged life and does not work hard.

Last week a hydraulic line (pipe under the tractor) ruptured (similar to an aneurysm) while I was simply traveling (about 2.0 mph). The failed line operated the bucket (the dump command).

I have since replaced the failed line with a factor part, changed the filters, and added new hydraulic oil. The bucket "dump" does not work now.

I called my local dealer and explained the problem. Although the problem was not solved I did learn that the system is self-purging and does not required bleeding of the hydraulic lines.

Does anyone have any idea as to what I need to do to get this command to work again?

Thank you all - Ron Fischer, Salem, Oregon
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
32,675
8,207
113
Sandpoint, ID
Only 2 real possibilities come to mind, you either you have a bad valve, or a bad cylinder.
Unless you have disconnected the quick couplers and have 2 of them swapped.