GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2009 🢒 Vibe - AWD 🢒 Engine 🢒 Engine Mechanical - 2.4L (LAX) 🢒 Piston, Connecting Rod, and Bearing Cleaning and Inspection

Connecting Rod and Bearing Inspection
  1. Install the connecting rod, rod bearings and rod cap on the correct rod journal.

    2. Object Number: 2018158 Size: SH
  2. Using a dial indicator, measure the thrust clearance while moving the connecting rod back and forth.

    3. Standard Thrust Clearance
    0.160 to 0.362 mm (0.0063 to 0.0143 in)

    Maximum Thrust Clearance
    0.362 mm (0.0143 in)

  3. If the thrust clearance is greater than the maximum, replace the connecting rod assemblies as necessary. If necessary, replace the crankshaft.
  4. Inspect connecting rod oil clearance.
  5. Clean the crank pin and bearing.
  6. Check the crank pin and bearing for pitting and scratches.

    7. Object Number: 2018159 Size: SH
  7. Lay a strip of Plastigage on the crank pin.

    8. Object Number: 2018160 Size: SH
  8. Check that the front mark of the connecting rod cap is facing forward.

    9. Important: Do not turn the crankshaft.

  9. Install the connecting rod cap.
  10. Remove the 2 bolts and connecting rod cap.

    11. Object Number: 2018161 Size: MH

    Important: Completely remove the Plastigage after the measurement.

    Important: If replacing a bearing, replace it with one that has the same number as its respective connecting rod cap. Each bearing standard thickness is indicated by a 1, 2, or 3 mark on its surface.

  11. Measure the Plastigage at its widest point.

    12. Standard Oil Clearance
    0.024 to 0.048 mm (0.0009 to 0.0019 in)

    Maximum Oil Clearance
    0.063 mm (0.0025 in)

  12. If the oil clearance is greater than the maximum, replace the connecting rod bearings. If necessary, inspect the crankshaft.

    13. Standard Crankshaft Pin Diameter
    47.990 to 48.000 (1.8894 to 1.8898 in)


    Object Number: 2017296 Size: SH
  13. Using a connecting rod aligner and feeler gauge, check the connecting rod alignment.
  14. Check for misalignment.

    15. Maximum Misalignment
    0.05 mm (0.0020 in) per 100 mm (3.94 in)

  15. If the misalignment is greater than the maximum, replace the connecting rod.

    16. Object Number: 2017297 Size: SH
  16. Check for twist.

    17. Maximum Twist
    0.05 mm (0.0020 in) per 100 mm (3.94 in)

  17. If the twist is greater than the maximum, replace the connecting rod.

    18. Object Number: 2018182 Size: SH
  18. Using vernier calipers, measure the tension portion diameter of the connecting rod bolt.

    19. Standard Diameter
    7.2 to 7.3 mm (0.283 to 0.287 in)

    Minimum Diameter
    7.0 mm (0.276 in)

  19. If the diameter is less than the minimum, replace the connecting rod bolt.

Piston and Ring Inspection

    Object Number: 2018165 Size: SH
  1. Using a gasket scraper, remove the carbon from the top of the piston.

    2. Object Number: 2018166 Size: SH
  2. Using a groove cleaning tool or a broken ring, clean the piston ring grooves.

    3. Object Number: 2018169 Size: SH
  3. Using a suitable cleaning brush and solvent, thoroughly clean the piston.

    4. Object Number: 2018170 Size: SH
  4. Using a micrometer, measure the piston diameter at right angles to the piston pin hole, and at the piston 44.3 mm (1.7441 in) from the piston head.

    5. Standard Piston Diameter
    88.469 to 88.479 mm (3.4830 to 3.4834 in)

  5. If the diameter is not as specified, replace the piston.
  6. Subtract the piston diameter measurement from the cylinder bore diameter measurement.

    7. Standard Oil Clearance
    0.021 to 0.044 mm (0.0008 to 0.0017 in)

    Maximum Oil Clearance
    0.10 mm (0.0039 in)

  7. If the oil clearance is greater than the maximum, replace all the pistons. If necessary, replace the cylinder block.

    8. Object Number: 2018171 Size: SH
  8. Using a feeler gauge, measure the clearance between a new piston ring and the wall of the ring groove.

    9. If the groove clearance is not as specified, replace the piston.


    Object Number: 2018172 Size: SH
  9. Using a piston, push the piston ring a little beyond the bottom of the ring travel, 110 mm (4.33 in) from the top of the cylinder block.

    10. Object Number: 2017285 Size: SH
  10. Using a feeler gauge, measure the end gap.

    11. If the end gap is greater than the maximum, replace the piston ring. If the end gap is greater than the maximum with a new piston ring, replace the cylinder block.


    Object Number: 2018174 Size: SH
  11. Using a caliper gauge, measure the piston pin bore diameter.

    12. Standard Piston Pin Bore Diameter
    22.001 to 22.010 mm (0.8662 to 0.8665 in)

  12. If the diameter is not as specified, replace the piston.

    13. Object Number: 2018177 Size: SH
  13. Using a micrometer, measure the piston pin diameter.

    14. Standard Piston Pin Diameter
    21.997 to 22.006 mm (0.8660 to 0.8664 in)

  14. If the diameter is not as specified, replace the piston pin.
  15. Using a caliper gauge, measure the connecting rod small end bore diameter.

    16. Standard Connecting Rod Small End Bore Diameter
    22.005 to 22.014 mm (0.8663 to 0.8667 in)

  16. If the diameter is not as specified, replace the connecting rod.

    17. Object Number: 2018180 Size: SH
  17. Subtract the piston pin diameter measurement from the piston pin bore diameter measurement.

    18. Standard Oil Clearance
    0.001 to 0.007 mm (0.00004 to 0.0003 in)

    Maximum Oil Clearance
    0.010 mm (0.0004 in)

  18. If the oil clearance is greater than the maximum, replace the connecting rod. If necessary, replace the piston and piston pin as a set.
  19. Subtract the piston pin diameter measurement from the connecting rod small end bore diameter measurement.

    20. Standard Oil Clearance
    0.005 to 0.011 mm (0.0002 to 0.0004 in)

    Maximum Oil Clearance
    0.011 mm (0.0004 in)

  20. If the oil clearance is greater than the maximum, replace the connecting rod. If necessary, replace the connecting rod and piston pin as a set.