BEARING-MAIN 0.25MM US 7C6961 - Caterpillar

Generator tests are to be performed by a trained Generator technician.
Check for vibration damage.Vibration may cause the following problems:
Coupling wear
Loose fittings
Fatigue of the metal components of the engine
Cracks in the cabinet which surrounds the generator
Cracks in welds
Excessive noise
Cracked insulationThe following areas are susceptible to vibration damage:
Coupling for the generator set
Generator bearings
Stator output leads
Protective sleeving
Insulation
Exposed electrical connections
Transformers
Fuses
Capacitors
Lightning arrestersWhen a generator set is installed, a vibration plot should be recorded to help in diagnosing potential problems. This vibration plot should be updated yearly. Update the vibration plot when the generator set is moved and when the engine is overhauled. This procedure will allow the trend of the vibration to be monitored and analyzed. A potential problem may be prevented by monitoring the trend of the vibration. If the vibration is approaching the limit of the specification of the component, the problem may be more imminent. Refer to Data Sheet, LEKQ4023, "Linear Vibration" for the allowable limits of vibration.Caterpillar also recommends recording the vibration of the bearing at the generator bearing bracket.If the vibration exceeds the EDS limits for vibration, check the alignment. Refer to this Operation and Maintenance Manual, "Generator Set Alignment - Check" for the alignment procedure.Contact the Cat Dealer Service Tools group for information on ordering a vibration analyzer that will meet your needs.