Crankshaft and Bearings Cleaning and Inspection (Inspection)

Tool Required 

J 7872  Magnetic Base Dial Indicator Set

1. Remove the clutch pilot bearing.
   Fig 1: Removing Clutch Pilot Bearing

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2. Clean the crankshaft with solvent.
3. Thoroughly clean all oil passages and inspect for restrictions or burrs.
   CAUTION: Wear safety glasses in order to avoid eye damage.
4. Dry the crankshaft with compressed air.

   Important:  Reluctor ring teeth should not have imperfections on the rising or falling edges.

   Imperfections of the reluctor ring teeth may effect OBD II system performance.

5. Perform a visual inspection of the crankshaft for damage.
   Fig 2: Inspecting Crankshaft

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6. Inspect the crankshaft journals for wear (1).

   Journals should be smooth with no signs of scoring, wear, or damage.

7. Inspect the crankshaft journals for grooves or scoring (2).
8. Inspect the crankshaft journals for scratches or wear (3).
9. Inspect the crankshaft journals for pitting or imbedded bearing material (4).
   Fig 3: Inspecting Crankshaft Journals

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10. Measure the crankshaft journals for out-of-round.
11. Measure the crankshaft journals for taper.
    Fig 4: Measuring Crankshaft Journals For Out-Of-Round And Taper

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12. Measure the crankshaft runout.

    Using wooden V blocks, support the crankshaft on the front and rear journals.

13. Use the J 7872  in order to measure the crankshaft runout at the front and rear intermediate journals.
14. Use the J 7872  in order to measure the runout of the crankshaft rear flange.
    1. 14.1. Compare the measurements to ENGINE MECHANICAL SPECIFICATIONS  .
    2. 14.2. Replace or repair the crankshaft if the measurements are not within the specifications.
       Fig 5: Measuring Crankshaft Runout

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15. Install a new clutch pilot bearing.

    A properly installed clutch pilot bearing will be installed until flush to the face of the crankshaft.

    Fig 6: Installing Clutch Pilot Bearing

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16. Inspect crankshaft bearings for craters or pockets. Flattened sections on the bearing halves also indicate fatigue.
    Fig 7: >Inspecting Crankshaft Bearings For Craters Or Pockets

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17. Inspect the crankshaft bearings for excessive scoring or discoloration.
18. Inspect the crankshaft bearings for dirt or debris imbedded into the bearing material.
    Fig 8: Inspecting Crankshaft Bearings For Excessive Scoring Or Discoloration

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19. Inspect the crankshaft bearings for improper seating indicated by bright, polished sections of the bearing.

    If the lower half of the bearing is worn or damaged, both upper and lower halves should be replaced.

    Generally, if the lower half is suitable for use, the upper half should also be suitable for us.

    Fig 9: Inspecting Crankshaft Bearings For Improper Seating

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