Bosch Rexroth A4VG 35 Series - Malfunction table

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RE92035-01-B/2019-11-25, A4VG Series35, Bosch Rexroth AG
14.2 Malfunction table
Table 13: Axial piston unit malfunction table
Malfunction Possible cause Remedy
Unusual noises 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, e.g.,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, suction filter too small or
blocked, etc.
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
Check the filter system and change the filter as
necessary
Drive speed too high Machine/system manufacturer: Reduce drive
speed
Wrong direction of rotation Machine/system manufacturer: Check correct
direction of rotation, seechapter 7.4.1
"Preparation" on page34
Improper mounting of the axial piston unit Check the mounting of the axial piston
unit according to the specifications of the
machine/system manufacturer – observe
tightening torques
Improper mounting of assembled parts,
hydraulic lines or improper installation of the
coupling
Fasten assembled parts according to the
information provided by the coupling fitting
manufacturer
Oscillate pressure relief valves and pressure
control valves in the axial piston unit
(boost-pressure relief valve, high-pressure relief
valve, pressure reducing valve)
Air bleed the axial piston unit and hydraulic
system
Contact BoschRexroth Service:
Optimize the setting of the pressure limitation
and pr
essure control valve
Mechanical damage to the axial piston unit
(e.g.bearing damage)
Replace axial piston unit
Contact BoschRexroth Service
Increased, unusual vibration Bearings worn Contact BoschRexroth Service