M-B MSV, Maintenance And Service Manual

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Troubleshooting 49/56
RE 93221-01-B/07.2013, A22VG Series 40, Bosch Rexroth AG
14.2 Malfunction table
Table 13: Axial piston unit malfunction table
Malfunction Possible cause Remedy
Unusual noises Drive speed too high. Machine/system manufacturer.
Wrong direction of rotation. Ensure correct direction of rotation.
Insufficient suction conditions, e.g. air in
the suction line, insufficient diameter of the
suction line, viscosity of the hydraulic fluid
too high, suction height too high, suction
pressure too low, contaminants in the
suction line (only relevant for the version
with boost pump). Machine or system manufacturer
(e.g. optimize inlet conditions, use suitable
hydraulic fluid).
Completely air bleed axial piston unit, fill
suction line with hydraulic fluid.
Remove contaminants from the suction line.
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 the attachment parts,
e.g. coupling and hydraulic lines. Fix attachment parts according to the
information provided by the coupling or
fitting manufacturer.
Pressure-relief valves on axial piston unit. Air bleed the axial piston unit
Check viscosity of the hydraulic fluid
Contact Bosch Rexroth Service.
Pressure-relief valve of the axial piston unit
(boost pressure, high pressure). Air bleed the axial piston unit
Check viscosity of the hydraulic fluid
Contact Bosch Rexroth Service.
Mechanical damage to the axial piston unit
(e.g. bearing damage). Exchange axial piston unit,
contact Bosch Rexroth Service.
No or insufficient flow Faulty mechanical drive
(e.g. defective coupling). Machine/system manufacturer.
Drive speed too low. Machine/system manufacturer.
Insufficient suction conditions, e.g. air in
the suction line, insufficient diameter of the
suction line, viscosity of the hydraulic fluid
too high, suction height too high, suction
pressure too low, contaminants in the
suction line (only relevant for the version
with boost pump). Machine or system manufacturer
(e.g. optimize inlet conditions, use suitable
hydraulic fluid).
Completely air bleed axial piston unit, fill
suction line with hydraulic fluid.
Remove contaminants from the suction line.
Hydraulic fluid not in optimum viscosity
range. Use suitable hydraulic fluid (machine/
system manufacturer).
External control of the control device
defective. Check external control (machine/system
manufacturer).
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.
Wear of axial piston unit. Exchange axial piston unit,
contact Bosch Rexroth Service.
Mechanical damage to the axial piston unit. Exchange axial piston unit,
contact Bosch Rexroth Service.