Hydraulics Stopped Working

[walk thru ko]

Have a S470 Buck with a FEL I use it regularly and all of a sudden the hydraulics stopped working, the FEL bucket will not lift any load whatsoever, with the bucket empty and full engine RPM I can get a little lift with the bucket. I had been using the FEL the day it stopped working, I mean one minute everything is working fine, next minute it's not working. The tiller on the 3PH showing the same symptons -very slow lift. Checked the hydraulic fluid level it was OK, drained fluid and pulled the in-line screen. The screen was moderately dirty and the fluid was moderately milky/dirty. Filled with new fluid and still not working. What's going on?????

 

[Leejohn]

Take a line off and see if you have flow. Made sure the pump is turning, might of broke the shaft. Could have a relief valve stuck open. After you find it make sure the relief is working and set right. One more thing check the inlet line to the pump and make sure it's not sucking air.

 

[J_J]

Have a S470 Buck with a FEL I use it regularly and all of a sudden the hydraulics stopped working, the FEL bucket will not lift any load whatsoever, with the bucket empty and full engine RPM I can get a little lift with the bucket. I had been using the FEL the day it stopped working, I mean one minute everything is working fine, next minute it's not working. The tiller on the 3PH showing the same symptons -very slow lift. Checked the hydraulic fluid level it was OK, drained fluid and pulled the in-line screen. The screen was moderately dirty and the fluid was moderately milky/dirty. Filled with new fluid and still not working. What's going on?????

Just one more good reason on to get and install a hyd gage in the hyd system to monitor and trouble shoot the hyd system.

Most people assume that if there is fluid level is good and the pump is turning that the cyl should be doing work.

Need to check hydflow, and if no flow, check suction, and open return line to tank.

QD's are another source of trouble. Re-seat and check flow, or remove and check flow.

If you can build pressure so the relief valve goes off, then you can assume the pump is working good.

No hyd flow means that there is no fluid, the pump is totally trashed, the valve spools are not moving in reference to the cables or lever, or 0 voltage to the solenoids, etc.