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Kubota KX121-2 hydraulic issues

Dhg07777

New Member
Joined
Mar 5, 2016
Messages
2
Location
St louis
I have a Kubota KX121-2 mini excavator that is having some hydraulic problems. It was working fine and it sat for 3-4 months. Then I started it back up and the main hydraulics do not work. ( tracks, boom and bucket) The secondary pump that runs the blade and turntable work well.
we noticed a hissing/air sound on startup for few second and hydraulics work for mere seconds then it stops completely. sometimes hear bubbles or air in the hydraulic tank ( tank is slightly overfilled)
On the KX121-2 there is very little electronics compared to my KX121-3( newer model)

It seems like there is a main relief valve stuck open, allowing fluid toflow back into the tank at a high rate ? Hydraulics are my weak spot.....

Has anyone had a similar issue ?
Thanks
Don
 

uffex

Senior Member
Joined
Jan 23, 2012
Messages
4,464
Location
Lincoln UK
Occupation
Admin
Good day Dh
I taken a look at the schematic and those circuits you are missing is protected by the same relief valve it would seem that from the description your diagnostics are correct, the other circuits according to my schematic are serviced by the same pump with split flow, that being the case it is unlikely that the pump is the issue. I suggest remove and inspect the relief valve.
Kind regards
Uffex
 
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