GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J 24086-B (KM 427) Piston Pin Remover/Installer Set
    • J 45059 Angle Meter
    • KM-470-B Angular Torque Gage

Removal Procedure


    Object Number: 1291382  Size: SH
  1. Remove the cylinder head with the intake manifold and the exhaust manifold attached. Refer to Cylinder Head Replacement .
  2. Remove the oil pan. Refer to Oil Pan Replacement .
  3. Remove the oil suction pipe bolts.
  4. Remove the oil suction pipe.

  5. Object Number: 1291383  Size: SH
  6. Move the piston to the bottom of the piston stroke.
  7. Mark the connecting rod cap for position.
  8. Remove the connecting rod cap bolts.
  9. Remove the connecting rod cap and the lower connecting rod bearing.
  10. Remove the upper piston connecting rod bearing.
  11. Ridge ream the cylinder wall.

  12. Object Number: 1291384  Size: SH

    Caution: Handle the piston carefully. Worn piston rings are sharp and may cause bodily injury.

  13. Remove the piston.
  14. Use a piston ring expander tool to expand the piston rings.
  15. Remove the piston rings.

  16. Object Number: 1241706  Size: SH
  17. Remove the piston pin from the piston and connecting rod assembly using J 24086-B  (1).
  18. Separate the piston from the connecting rod.

Installation Procedure


    Object Number: 1241706  Size: SH
  1. Align the notch on the piston and the connecting rod so that the proper sides will be facing the front of the engine.
  2. Install the piston pin guide through the piston and the connecting rod.
  3. Coat the piston pin with clean oil.
  4. Install the piston pin into the opposite side of the piston.
  5. Install the piston pin into the piston and connecting rod assembly using J 24086-B  (1).
  6. Select a set of new piston rings.
  7. Measure the piston ring gap using a feeler gage. Refer to Engine Mechanical Specifications .
  8. Increase the piston ring gap by carefully filing off excess material if the piston ring gap is below specifications.

  9. Object Number: 1289598  Size: SH
  10. Measure the piston ring side clearance using a feeler gage. Refer to Engine Mechanical Specifications .
  11. If the piston ring is too thick, try another piston ring.
  12. If no piston ring can be found that fits to specifications, the piston ring may be ground to size with emery paper placed on a sheet of glass.

  13. Object Number: 1289611  Size: SH
  14. Install a piston oil ring, the expander, then the second piston oil ring to the bottom ring groove of the piston.
  15. Install the second compression ring to the middle ring groove of the piston.
  16. Install the top compression ring to the top ring groove of the piston.

  17. Object Number: 1289625  Size: SH
  18. Use a piston ring expander to install the piston rings. Do not expand the piston rings beyond the expansion necessary for installation.
  19. Stagger the piston oil rings (3) , the oil ring rail gaps (1), the second compression ring (4), and the top compression ring (3) in relation to the notch on the top of the piston (2).

  20. Object Number: 1289640  Size: SH
  21. Lubricate the cylinder wall and the piston rings with clean engine oil.
  22. Install the piston using a ring compressor and a wood handle. Guide the lower connecting rod end to prevent damaging the crankshaft journal.
  23. Install the connecting rod cap and bearings. Refer to Crankshaft and Bearing Cleaning and Inspection .
  24. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1289653  Size: SH
  25. Install the connecting rod cap bolts.
  26. Tighten
    Tighten the connecting rod bearing cap bolts to 25 N·m (18 lb ft). Using the J 45059 , tighten the bolts one turn of 30 degrees plus one turn of 15 degrees.


    Object Number: 1291382  Size: SH
  27. Install the oil suction pipe.
  28. Install the oil suction pipe bolts.
  29. Tighten
    Tighten the oil suction pipe bolts to 10 N·m (89 lb in).

  30. Install the oil pan. Refer to Oil Pan Replacement .
  31. Install the cylinder head with the intake manifold and the exhaust manifold attached. Refer to Cylinder Head Replacement .