kobelco sk120 mark v critical problem

kobelco sk 120 mark v long arm
this machine repaired cobelco agent, these are they have done.

main hydraulics pump overhaul
pilot pump change
pump proportional solenoid change
all filters & hyd oil change
pressure relief valve change

but still machine is not OK.

:Banghead:Banghead:Banghead:Banghead

both tracks is OK. ( relief pressure 350bar )
boom is not OK. ( relief pressure approximately 170bar )
arm is not OK. ( relief pressure approximately 180bar )
bucket is...

kobelco sk120 mark v critical problem

kobelco sk120 mark v critical problem