GM Service Manual Online
For 1990-2009 cars only

Tools Required

    • J-36792 (KM-635) Crankshaft Rear Oil Seal Installer
    • J 42492-A (KM 421-A) Timing Belt Adjuster
    • J 45059 Angle Meter
    • KM-470-B Angular Torque Gage
    • OTC 1726 (KM 412) Engine Overhaul Stand

Disassembly Procedure

    Caution: Refer to Safety Glasses Caution in the Preface section.


    Object Number: 1241783  Size: SH

    Important: Take extreme care to prevent any scratches, nicks, or damage to the crankshaft. Such damage can impair vehicle operation.

  1. Remove the engine. Refer to Engine Replacement.
  2. Remove the flywheel bolts.
  3. Remove the flywheel.
  4. Remove the crankshaft rear oil seal.
  5. Mount the engine assembly on the OTC 1726 .

  6. Object Number: 1241786  Size: SH
  7. Remove the upper timing belt cover bolts.
  8. Remove the upper timing belt cover.
  9. Remove the lower timing belt cover bolts.
  10. Remove the lower timing belt cover.

  11. Object Number: 1241553  Size: SH
  12. Slightly loosen the 3 coolant pump retaining bolts.
  13. Rotate the coolant pump using the J 42492-A  (1) to remove the tension from the timing belt. Remove the timing belt.

  14. Object Number: 1241557  Size: SH
  15. Remove the valve cover bolts.
  16. Remove the valve cover and the valve cover gasket.
  17. Important: Take extreme care to prevent any scratches, nicks, or damage to the camshaft. Such damage can impair vehicle operation.

  18. While holding the camshaft firmly in place, remove the camshaft gear bolt.
  19. Remove the camshaft gear.

  20. Object Number: 1241787  Size: SH
  21. Remove the timing belt automatic tensioner bolt (1).
  22. Remove the timing belt automatic tensioner.
  23. Remove the rear timing belt cover bolts.
  24. Remove the rear timing belt cover.
  25. Remove the crankshaft timing belt gear.

  26. Object Number: 1241642  Size: SH
  27. Rotate the engine on the OTC 1726 .
  28. Remove the oil pan retaining bolts.
  29. Remove the oil pan.
  30. Remove the oil pan pickup tube bolts.
  31. Remove the oil pump pickup tube.

  32. Object Number: 1241645  Size: SH
  33. Remove the oil pump retaining bolts (1).
  34. Remove the oil pump.

  35. Object Number: 1241793  Size: SH
  36. Mark the order of the rod bearing caps.
  37. Remove the connecting rod cap bolts for all of the pistons.
  38. Remove the connecting rod bearing caps and the lower connecting rod bearings.
  39. Remove the upper connecting rod bearings.

  40. Object Number: 1241791  Size: SH
  41. Mark the order of the crankshaft bearing caps.
  42. Remove the crankshaft bearing cap bolts.
  43. Remove the crankshaft bearing caps.
  44. Remove the crankshaft bearings from the crankshaft bearing caps.
  45. Remove the crankshaft.
  46. Remove the crankshaft bearings from the engine block.
  47. Caution: Refer to Safety Glasses Caution in the Preface section.

  48. Clean the parts as necessary.

Assembly Procedure


    Object Number: 1241789  Size: SH
  1. With the crankshaft and bearings in place, plastic gage all bearing clearances. Refer to Crankshaft and Bearing Cleaning and Inspection.
  2. Inspect the crankshaft end play with the crankshaft bearings installed.
  3. Inspect for permissible crankshaft end play. Refer to Engine Mechanical Specifications.

  4. Object Number: 1241794  Size: SH
  5. With the crankshaft mounted on the front and the rear crankshaft bearings, check the middle crankshaft bearings. Check the middle crankshaft journal for permissible out-of-round runout. Refer to Engine Mechanical Specifications.

  6. Object Number: 1241795  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: 1241797  Size: SH
  12. Install the crankshaft bearings to the crankshaft bearing caps.
  13. Install the crankshaft bearing caps.
  14. Notice: Refer to Fastener Notice in the Preface section.

    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 new crankshaft bearing cap bolts.
  16. Tighten

    1. Tighten the crankshaft bearing cap bolts to 50 N·m (37 lb ft).
    2. Using the J 45059 or the KM-470-B  (1), tighten the crankshaft bearing cap bolts another 45 degrees plus 15 degrees.
  17. Install the upper connecting rod bearings to the connecting rods.
  18. Install the lower connecting rod bearings to the connecting rod bearing caps.

  19. Object Number: 1241793  Size: SH
  20. Install the connecting rod bearing caps to the connecting rods.
  21. Install new connecting rod bearing cap bolts.
  22. Tighten

    1. Tighten the connecting rod bearing cap bolts to 25 N·m (18 lb ft).
    2. Using the J 45059 or the KM-470-B , tighten the connecting rod bearing cap bolts another 30 degrees.

    Object Number: 1241645  Size: SH
  23. Install the oil pump.
  24. Install the oil pump retaining bolts (1).
  25. Tighten
    Tighten the oil pump retaining bolts to 10 N·m (89 lb in).


    Object Number: 1241642  Size: SH
  26. Install the oil pump/pickup tube.
  27. Install the oil pump/pickup tube bolts.
  28. Tighten
    Tighten the oil pump/pickup tube and support bracket bolts to 10 N·m (89 lb in).


    Object Number: 1241657  Size: SH
  29. Install the oil pan gasket to the oil pan.
  30. Install the oil pan.
  31. Important: Install the oil pan within 5 minutes after applying the liquid gasket to the oil pan.

  32. Install the oil pan retaining bolts.
  33. Tighten
    Tighten the oil pan retaining bolts to 10 N·m (89 lb in).


    Object Number: 1241787  Size: SH
  34. Install the crankshaft timing belt gear.
  35. Install the rear timing belt cover.
  36. Install the rear timing belt cover bolts.
  37. Tighten
    Tighten the rear timing belt cover bolts to 10 N·m (89 lb in).

  38. Install the timing belt automatic tensioner.
  39. Install the timing belt automatic tensioner bolt (1).
  40. Tighten
    Tighten the timing belt automatic tensioner bolt to 20 N·m (15 lb ft).


    Object Number: 1241557  Size: SH

    Important: Take extreme care to prevent any scratches, nicks, or damage to the camshaft. Such damage can impair vehicle operation.

  41. Install the camshaft gear.
  42. Install the camshaft gear bolt while holding the camshaft firmly in place.
  43. Tighten
    Tighten the camshaft gear bolt to 45 N·m (33 lb ft).


    Object Number: 1241552  Size: SH
  44. Install the timing belt.
  45. Adjust the timing belt tension. Refer to Timing Belt Inspection.
  46. Install the valve cover gasket and the valve cover.
  47. Install the valve cover bolts.
  48. Tighten
    Tighten the valve cover bolts to 9 N·m (80 lb in).

  49. Install the lower timing belt cover.
  50. Install the lower timing belt cover bolts.
  51. Tighten
    Tighten the lower timing belt cover bolts to 10 N·m (89 lb in).


    Object Number: 1241798  Size: SH
  52. Install the power steering pump.
  53. Install the power steering pump mounting bolts.
  54. Tighten
    Tighten the power steering pump mounting bolts to 25 N·m (18 lb ft).

  55. Install the upper timing belt cover.
  56. Install the upper timing belt cover bolts.
  57. Tighten
    Tighten the upper timing belt cover bolts to 10 N·m (89 lb in).

  58. Install the engine lifting device.
  59. Dismount the engine from the OTC 1726 .
  60. Install the crankshaft rear oil seal using the J-36792  (1) or KM-635 .

  61. Object Number: 1241783  Size: SH
  62. Install the flywheel.
  63. Install the flywheel bolts.
  64. Tighten

    1. Tighten the flywheel bolts to 35 N·m (26 lb ft) using a torque wrench.
    2. Using the J 45059 or the KM-470-B , tighten the flywheel bolts another 30 degrees plus 15 degrees.
  65. Install the engine. Refer to Engine Replacement.