How to prepare for Auxiliary Engine overhau?

22 Oct '21, 09:18

Oct. 22, 2021, 9:18 a.m.
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Auxiliary Engine / Four Stroke Engine overhaul should be planned well in advance (minimum three months prior intended overhauling date) in coordination with the office / Vessel Manager.

Requirement for spares, tools and services should assessed and orders placed timely.

Points listed below should be confirmed before commencing:

1) The running hours clocked and maker’s recommendations on service life are checked to decide on the spare’s requirement.

2) Adequate spares available for overhaul:

  • Consumables and piston rings
  • Connecting rod bolts (should be renewed every alternate overhaul or earlier, if maker requires so)
  • Spare connecting rods (should be renewed at the maker's recommended interval or based on bore / ovality measurements or condition assessment during overhaul)
  • Crankpin bearing shells (should be renewed at maker's recommended interval or based on condition assessment during overhaul)

3) Availability of special tools required for the overhaul:

  • Micrometres of correct size for measurement of crankpin diameter, connecting rod bore and cylinder liner
  • Hydraulic jacks and torque wrenches for tightening of bottom end bearing bolts / nuts and cylinder head nuts
  • Stand for placing pistons
  • Any other special tools as relevant

4) Spare connecting rods are reconditioned by a competent workshop and calibration reports post reconditioning are available and showing conformance to maker’s standards

5) Tightening tools (hydraulic pressure gauges and torque wrenches) for bottom end bolts are calibrated – should have been calibrated within a year prior (not longer than a year before) being used

6) Following are recorded and assessed before commencement:

  • Performance Report at maximum load (minimum 80% of rated capacity, if feasible)
  • Bearing clearances prior overhaul
  • Crankshaft deflection prior overhaul
  • Resilient mounting condition and clearance measurements (as applicable)

7) Ship staff is well familiar with following procedures, and confident of ability to follow these precisely:

  • relevant Company’s or maker guidelines
  • Maker’s recommended maintenance procedures for unit overhaul of the specific generator model – including connecting rod checks and tightening procedure
  • Chief Engineer to supervise the connecting rod assembly and tightening of the connecting rod bottom end bolts and nuts
  • Release / opening pressure of hydraulic fasteners to be measured and recorded when opening the unit for overhaul
  • Progress on overhaul to be closely communicated to the Vessel Manager daily, along with information on the observations on the condition and any concerns (noted from visual checks and measurements)
  • Post overhaul checks / engine trials as specified in “Medium Speed Four Stroke Engine Overhaul or maker manual

8) Any requirement for engaging maker’s service engineer / specialist or other resources (workshop) for supervising the auxiliary engine overhaul to be assessed. In case the requirement is foreseen, same to be arranged.

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22 Oct '21, 09:38

Oct. 22, 2021, 9:38 a.m.
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