GM Service Manual Online
For 1990-2009 cars only

Tools Required

OTC 1726 (KM-412) Engine Overhaul Stand

Disassembly Procedure


    Object Number: 1240785  Size: SH
  1. Remove the engine. Refer to Engine Replacement .
  2. Remove the transaxle from the engine. Refer to Transmission Replacement in Manual Transmission (Y4M).
  3. Remove the flywheel bolts.
  4. Remove the flywheel.
  5. Mount the engine assembly on the OTC 1726 .

  6. Object Number: 1240787  Size: SH
  7. Remove the cylinder head. Refer to Cylinder Head Replacement .
  8. Drain the engine oil from the engine.
  9. Remove the power steering adjusting bolts.
  10. Remove the power steering/air conditioning (A/C) belt.

  11. Object Number: 1240788  Size: SH
  12. Turn the A/C compressor downward.
  13. Remove the A/C compressor/power steering bracket bolts.
  14. Remove the A/C compressor/power steering bracket.

  15. Object Number: 1230300  Size: SH
  16. Loosen the generator bolt (1).
  17. Loosen the generator lower bolts and the nut (3).
  18. Remove the generator and belt (2).

  19. Object Number: 1230302  Size: SH
  20. Loosen the engine mount upper bracket bolts (5).
  21. Remove the generator shackle (2).
  22. Remove the upper bracket (1).
  23. Loosen the engine mount lower bracket bolts (4).
  24. Remove the lower bracket (3).

  25. Object Number: 1240789  Size: SH
  26. Remove the upper timing belt cover bolts.
  27. Remove the upper timing belt cover.

  28. Object Number: 1240792  Size: SH
  29. Remove the lower timing belt cover bolts.
  30. Remove the lower timing belt cover.

  31. Object Number: 1240793  Size: SH
  32. Loosen the timing belt automatic tensioner (3) bolt.
  33. Remove the automatic tensioner from the timing belt (1).
  34. Remove the timing belt.

  35. Object Number: 1240794  Size: SH
  36. Rotate the engine on the OTC 1726 .
  37. Remove the oil pan retaining bolts and the nuts.
  38. Remove the oil pan.

  39. Object Number: 1240795  Size: SH
  40. Remove the oil pan pickup tube bolts.
  41. Remove the oil pan pickup tube.

  42. Object Number: 1240796  Size: SH
  43. Remove the oil pump retaining bolts.
  44. Remove the oil pump.

  45. Object Number: 1240798  Size: SH
  46. Remove the crankshaft rear oil seal housing screws and bolts.
  47. Remove the gasket and the oil seal housing.

  48. Object Number: 1240799  Size: SH
  49. Mark the order of the rod bearing caps.
  50. Remove the connecting rod cap nuts (1) for all of the pistons.
  51. Remove the connecting rod bearing caps and the lower connecting rod bearing.
  52. Remove the upper connecting rod bearing.
  53. Mark the order of the crankshaft bearing caps.
  54. Remove the crankshaft bearing cap bolts (2).
  55. Remove the crankshaft bearing cap.
  56. Remove the crankshaft bearings from the crankshaft bearing caps.
  57. Remove the crankshaft.
  58. Remove the crankshaft bearings from the engine block.
  59. Caution: Wear safety glasses in order to avoid eye damage.

  60. Clean the parts, as necessary.

Assembly Procedure


    Object Number: 1240800  Size: SH
  1. With the crankshaft and the bearings in place, plastic gage all bearing clearances. Refer to Piston, Connecting Rod, and Bearing Cleaning and Inspection .
  2. Inspect the crankshaft end play with the crankshaft bearings installed.
  3. Check the permissible crankshaft end play. Refer to Engine Mechanical Specifications .

  4. Object Number: 1240801  Size: SH
  5. With the crankshaft mounted on the front and the rear crankshaft bearings, inspect the middle crankshaft journal for permissible out-of-round, runout. Refer to Engine Mechanical Specifications .

  6. Object Number: 1240813  Size: SH
  7. Coat the crankshaft bearings with engine oil.
  8. Apply a bead of adhesive sealing compound to the grooves of the rear crankshaft bearing cap.
  9. Install the crankshaft bearings in the engine block.
  10. Install the crankshaft.

  11. Object Number: 1241455  Size: SH

    Important: Grease the crankshaft journals and lubricate the crankshaft bearings slightly so that the plastic gaging thread does not tear when the crankshaft bearings are removed.

  12. Inspect all of the crankshaft bearing clearances using a commercially available plastic gaging--ductile plastic threads.
  13. Cut the plastic gaging threads to the length of the bearing width (1). Lay them between the crankshaft journals and the crankshaft bearings.

  14. Object Number: 1240799  Size: SH

    Notice: Do not reuse crankshaft bearing cap bolts. Failure to replace the crankshaft bearing cap bolts can lead to crankshaft bearing cap bolt breakage or crankshaft bearing failure. A broken crankshaft bearing bolt can lead to extensive engine damage.

  15. Install the crankshaft bearings to the crankshaft bearing caps.
  16. Notice: Refer to Fastener Notice in the Preface section.

  17. Install the crankshaft bearing caps bolts (2).
  18. Tighten
    Tighten the crankshaft bearing cap bolts to 57 N·m (42 lb ft).


    Object Number: 1241457  Size: SH
  19. Remove the crankshaft bearing caps.
  20. Using a ruler, measure the width of the flattened plastic thread of the plastic gaging. Plastic gaging is available for different tolerance ranges.
  21. Inspect the bearing clearances for permissible tolerance ranges. Refer to Engine Mechanical Specifications .