Troubleshooting - Sauer Danfoss 51 Series Service Manual

Bent Axis Variable Displacement Motors

Troubleshooting

Fault-Logic Diagrams • Closed Circuit
Check Oil Level
OK
in Reservoir
Low
Fill to Proper
Level
SYSTEM RESPONSE IS SLUGGISH
Check Oil
OK
Level in
Reservoir
Low
Fill to Proper
Level
EXCESSIVE NOISE AND/OR VIBRATION
Check Oil Level
OK
in Reservoir
Low
Fill to Proper
Level
Replace
Transmission
(Pump and Motor)
SYSTEM OPERATING HOT
30 - 15
Check System
Relief Valve
Pressure
Settings
Defective
Adjust or
Replace
Replace
Transmission
(Pump and Motor)
Air in System
OK
Loose Fitting
Purge Air and
Tighten
Fittings
Inspect Heat
OK
Exchanger
Defective
Clean, Repair
or Replace
Check System
OK
Pressure
High
Reduce Load on
Transmission
Check Pump
OK
Inlet Pressure
Low
Inspect Inlet Filter
and Replace if
Necessary
Check System
OK
Internal Leakage
High
Repair as Required
Check Pump
OK
Inlet Pressure
Low
Inspect Inlet Filter
and Replace if
Necessary
Check Charge
Pressure
Incorrect
Repair as
Required
Check for Internal
OK
System Leakage
High
Repair as Required
Check Prime Mover
OK
Speed
Low
Adjust
Check Charge and
OK
Control Pressures
Incorrect
Repair as Required
Inspect Shaft
OK
Couplings
Defective
Repair or
Replace
Check Pump Inlet
OK
Pressure
Low
Inspect Inlet Filter
and Replace if
Necessary
Check System Relief
OK
Pressure Settings
Adjust or Replace
Series 51
OK
Inspect Shaft
Alignment
Defective
Align Shafts
OK
Low
37