Bobcat 325 Mini-ex hydraulic problem

[shantie]

My Bobcat 325 Mini excavator has lost all function on the right-hand side, I have tested the relief valves, and the hydraulic pump, everything seems fine. looking for ideas to check next

 

[oldnslo]

Is the joystick hydraulic pilot or electric on that model? Either way I would check to see if getting a pilot signal or command from joystick to valves.

 

[shantie]

joystick hydraulic pilot

 

[shantie]

All left side controls are functional, and all auxiliary (blade and boom swing) controls work

 

[oldnslo]

I would double check to confirm that you are getting pilot pressure to the right joystick. Some of those systems had “pilot supply” valves for each joystick vs one common supply valve that you could have is controlled by the safety circuit.

 

[shantie]

I forgot to add that I do not have any right-hand drive as well, there doesn't seem to be any hydraulic pressure on the right-hand valve bank, I have tested the pump 1 which is producing the appropriate pressure.

 

[oldnslo]

Do you have a hydraulic schematic? Your system could have unloading valve for each pump vs a common unloading valve. I believe some excavators where built this way.

 

[shantie]

Do you have a hydraulic schematic? Your system could have unloading valve for each pump vs a common unloading valve. I believe some excavators where built this way.

Yes I have the service manual and the hydraulic schematic the unit is set up as ISO controls so on the right joy stick is the boom controls and bucket control, the right travel is a foot/rod control. Could a failed valve be letting oil dump bank to tank?

 

[oldnslo]

Yes I have the service manual and the hydraulic schematic the unit is set up as ISO controls so on the right joy stick is the boom controls and bucket control, the right travel is a foot/rod control. Could a failed valve be letting oil dump bank to tank?

Depending on how the circuit is setup it may have a valve or valves to unload the pump or pumps. Can you attach a picture or pdf of the hydraulic schematic showing the pumps, control valves, joysticks, etc. That could help us identify potential valve or valves that could cause the problem you are experiencing.

 

[shantie]

Attached files from service manual