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For 1990-2009 cars only

Piston, Connecting Rod, and Bearing Cleaning and Inspection Plastigage Method


    Object Number: 1936756  Size: LH
  1. Remove the oil pan. Refer to 1401312 - Oil Pan, Remove and Install.
  2. Remove the con-rod bearing cap.
  3. • Mark the installation position (1) of the con-rod bearing cap.
    • Unscrew the 2 bolts.
    • Degrease the con-rod bearing cap and wet the con-rod bearing clip with engine oil.

    Important: Do not rotate the crankshaft.

    Important: Plastigage is available via the "Opel/Vauxhall Workshop Equipment" catalogue.

  4. Lay on Plastigage.
  5. Lay Plastigage (flexible plastic thread) over the entire width of the con-rod bearing journal.

    Notice: Refer to Fastener Notice in the Preface section.

  6. Install the con-rod bearing cap.
  7. Tighten
    Tighten the 2 bolts to 35 N·m+45°+15°.

  8. Remove the con-rod bearing cap.
  9. Unscrew the 2 bolts.


    Object Number: 1936787  Size: LH

    Important: When reading the value, do not confuse millimeters and inches on the measuring scale.

  10. Measure the con-rod bearing play.
  11. • Compare the width of the flattened plastic thread with the measuring scale.
    • Permissible con-rod bearing play: 0.019-0.071 mm.

    Important: Check markings on parts.

  12. Install the con-rod bearing cap.
  13. • Wet the con-rod bearing journal and con-rod bearing clips with engine oil.
    • Renew the bolts.

    Tighten
    Tighten the 2 bolts to 35 N·m+45°+15°.

  14. Install the oil pan. Refer to 1401312 - Oil Pan, Remove and Install.

Piston, Connecting Rod, and Bearing Cleaning and Inspection Measuring Device Method


    Object Number: 1948722  Size: MH
  1. Install the inner plunger and calibrate with the micrometer gauge (1).
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Mount the con-rod bearing cover on the con-rod.
  4. Tighten
    Tighten the 2 bolts to 35 N·m+45°+15°.

  5. Measure the con-rod bearing diameters at 3 points.
  6. Measure at points I, II and III with the internal measuring device.


    Object Number: 1948723  Size: MH
  7. Work out the average con-rod diameter.
  8. Formula: I + II + III/3.

  9. Measure the con-rod bearing journal diameter at 2 points.
  10. Measure at points I and II with the micrometer gauge.

  11. Work out the average con-rod bearing journal diameter.
  12. Formula: I + II/2.

  13. Determine the con-rod bearing play.
  14. Calculation formula: average con-rod bearing diameter - average con-rod bearing journal diameter.

  15. Perform the target/actual comparison.
  16. Permissible con-rod bearing play: 0.019-0.071 mm.