Kubota l45 loader auxiliary third function under performing, help appreciated

[cfiondella]

Hi, I’m trying to understand and diagnose an issue im having with the auxiliary function on my loader. This is a push button on the loader lever activation that controls a solenoid that moves the hydraulic shuttle. All other functions on the tractor and loader seem fine and are what im used to. The auxiliary loader function is underpowered though. It works fine under light load like when operating a grapple but under high load application like operating a hammer, it stalls or bypasses. I don‘t see a seperate relief valve for the aux in the manual. something that seems diagnostic is when the loader boom is activated either up or down, the hammer will have power until the boom lever is moved back to neutral and then it will stall again. The hammer works normally on other machines. any help understanding the circuit or diagnosing the problem would be much appreciated. Thank you!

 

[TheOldHokie]

Hi, I’m trying to understand and diagnose an issue im having with the auxiliary function on my loader. This is a push button on the loader lever activation that controls a solenoid that moves the hydraulic shuttle. All other functions on the tractor and loader seem fine and are what im used to. The auxiliary loader function is underpowered though. It works fine under light load like when operating a grapple but under high load application like operating a hammer, it stalls or bypasses. I don‘t see a seperate relief valve for the aux in the manual. something that seems diagnostic is when the loader boom is activated either up or down, the hammer will have power until the boom lever is moved back to neutral and then it will stall again. The hammer works normally on other machines. any help understanding the circuit or diagnosing the problem would be much appreciated. Thank you!

According to the schematic the 3rd function is fed by the loader valve. It should be seeing the same flow and pressure as the loader. Interesting that it works better wirh the boom spool shifted. That puts it in series with the boom cylinders. Not dure whst to make of that....

Dan

 

[cfiondella]

According to the schematic the 3rd function is fed by the loader valve. It should be seeing the same flow and pressure as the loader. Interesting that it works better wirh the boom spool shifted. That puts it in series with the boom cylinders. Not dure whst to make of that....

Dan

I wasn’t either, thanks for the reply though, hopefully someone will have a good idea. Maybe when the boom spool is in neutral it’s bypassing somehow?

 

[TheOldHokie]

I wasn’t either, thanks for the reply though, hopefully someone will have a good idea. Maybe when the boom spool is in neutral it’s bypassing somehow?

I dont know about bypass but wirh the loader spool in lift the cylinders can act as pressure intensifiers and give you a higher inlet pressure at the 3rd function.

Dan