Troubleshooting 55/60
RE 92801-01-B/11.2018, A15VSO/A15VLO Series 11, BoschRexrothAG
Table 15: Axial piston unit malfunction table
Malfunction Possible cause Remedy
No orinsufficient pressure Insufficient air bleeding ofthehydraulic system Fill the axial piston unit, suction line for the
hydraulic pump and the reservoir
Completely air bleed the axial piston unit and
hydraulic system
Check correct installation position
Faulty mechanical drive (e.g.defective coupling) Contact machine/system manufacturer
Drive power too low Contact machine/system manufacturer
Insufficient suction conditions, e.g.insufficient
dimensioning ofthesuction line, viscosity
ofthehydraulic fluid too high, suction height
too high, suction pressure too low, foreign
particles inthe suction line, impermissible filter
inthe suction line
Machine/system manufacturer: Check the
system, e.g.optimize inlet conditions, use
suitable hydraulic fluid
Fill the suction line with hydraulic fluid
Remove foreign particles from the suction line
Hydraulic fluid not inoptimal viscosity range Machine/system manufacturer:
Check temperature range and use suitable
hydr
aulic fluid
Insufficient pilot pressure orcontrol pressure Check pilot pressure orcontrol pressure
Contact BoschRexrothService
Malfunction ofthecontrol device orcontroller
oftheaxial piston unit
Contact BoschRexrothService
Control ofthecontrol device defective Check control (contact machine/system
manufacturer orBoschRexrothService)
Wear ormechanical damage tothe axial
pistonunit
Replace axial piston unit
Contact BoschRexrothService
Output unit defective (e.g.hydraulic motor
orcylinder)
Contact machine/system manufacturer
Pressure/flow fluctuations/
instabilities
Insufficient air bleeding ofthehydraulic system Fill the axial piston unit, suction line for the
hydraulic pump and the reservoir
Completely air bleed the axial piston unit and
hydraulic system
Check correct installation position
Insufficient suction conditions, e.g.insufficient
dimensioning ofthesuction line, viscosity
ofthehydraulic fluid too high, suction height
too high, suction pressure too low, foreign
particles inthe suction line, impermissible filter
inthe suction line
Machine/system manufacturer: Check the
system, e.g.optimize inlet conditions, use
suitable hydraulic fluid
Fill the suction line with hydraulic fluid
Remove foreign particles from the suction line
Valve and controller vibrate Optimize the adjustment ofthecontroller
oftheaxial piston unit and the pressure
limitation inthe hydraulic system
Unstable control signal Contact machine/system manufacturer
orBoschRexrothService
Malfunction inthe control devices
orthecontroller
Contact BoschRexrothService