Troubleshooting 55/60
RE 92701-01-B/04.2018, A10VO, A10VSO Series 31,
Bosch Rexroth AG
Table 14: Axial piston unit malfunction table
Malfunction
Possible cause
Remedy
No or insufficient pressure
Insufficient air bleeding of the hydraulic 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 (for example, defective
coupling)
Contact machine/system manufacturer
Drive power too low
Contact machine/system manufacturer
Insufficient suction conditions, for example,
insufficient dimensioning of the suction line,
viscosity of the hydraulic fluid too high,
suction height too high, suction pressure
too low, foreign particles in the suction line,
impermissible filter in the suction line
Machine/system manufacturer: check the
system, for example, optimize inlet conditions,
use suitable hydraulic fluid
Fill the suction line with hydraulic fluid
Remove foreign particles from the suction line
Hydraulic fluid not in optimal viscosity range
Machine/system manufacturer:
Check temperature range and use suitable
hydraulic fluid
Insufficient pilot pressure or control pressure
Check pilot pressure or control pressure
Contact Bosch Rexroth Service
Malfunction of the control device or controller
of the axial piston unit
Contact Bosch Rexroth Service
Control of the control device defective
Check control (contact machine/system
manufacturer or Bosch Rexroth Service)
Wear or mechanical damage to the axial
piston unit
Replace axial piston unit
Contact Bosch Rexroth Service
Output unit defective (e.g. hydraulic motor or
cylinder)
Contact machine/system manufacturer
Pressure/flow fluctuations/
instabilities
Insufficient air bleeding of the hydraulic 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, for example,
insufficient dimensioning of the suction line,
viscosity of the hydraulic fluid too high,
suction height too high, suction pressure
too low, foreign particles in the suction line,
impermissible filter in the suction line
Machine/system manufacturer: check the
system, for example, 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 of the axial piston
unit and the pressure limitation in the hydraulic
system
Unstable control signal
Contact machine/system manufacturer or Bosch
Rexroth Service
Malfunction in the control devices or the
controller
Contact Bosch Rexroth Service
