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Main Engine thrust bearing

Main Engine thrust bearing


Subj : confirmation of bearing axial clearance


Axial clearance can be checked with the following simple method :

  • use the magnetic base of  a dial gauge
  • remove the dial gauge
  • take a steel electrode and make one end sharply pointed by grinding
  • attach the electrode firmly on the magnetic base
  • paint a stripe of white paint on the intermediate shaft – near to intermediate shaftbearing foundation
  • attach the magnetic base on the foundation of the intermediate bearing in such  a way that the pointed end of the electrode rests only a few millimeters away from the intermediate  shaft in way of the freshly painted white stripe
  • start the engine in AHEAD direction and push the pointed end of the electrode on the freshly painted white stripe. The small line inscribed on the  shaft is the AHEAD line.
  • stop the engine and start again in the ASTERN direction. Push the pointed end of the electrode on the freshly painted white stripe. The small line inscribed on the shaft is the ASTERN line.
  • measure carefully the distance between AHEAD line & ASTERN line using a vernier caliper to find the clearance of the thrust bearing


Please note that this is a verification method which does not replace the conventional
method of finding the clearance using feeler gauges.

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