GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Optra 🢒 Engine 🢒 Engine Mechanical - 1.8L (L79) 🢒 Cylinder Head Replacement

Tools Required
    • J 45059 Angle Meter
    • KM-470-B Angular Meter Gage
    • J 28467-B (DW 117) Universal Engine Support Fixture

Removal Procedure

    Object Number: 1289766 Size: SH
  1. Remove the fuel pump fuse.
  2. Start the engine. After it stalls, crank the engine for 10 seconds to rid the fuel system of fuel pressure.

    3. Caution: Refer to Battery Disconnect Caution in the Preface section.

  3. Disconnect the negative battery cable.
  4. Disconnect the electronic control module (ECM) ground terminal.
  5. Drain the engine coolant. Refer to Cooling System Draining and Filling .

    6. Object Number: 1289768 Size: SH
  6. Disconnect the intake air temperature (IAT) sensor connector.
  7. Disconnect the breather tube from the camshaft cover.
  8. Disconnect the air cleaner outlet hose from the throttle body.

    9. Object Number: 1289769 Size: SH
  9. Disconnect the direct ignition system (DIS) coil connector.
  10. Disconnect the oxygen sensor (O2S) connector, if equipped.
  11. Disconnect the idle air control (IAC) valve connector.
  12. Disconnect the throttle position (TP) sensor connector.
  13. Disconnect the engine coolant temperature (ECT) sensor connector.
  14. Disconnect the coolant temperature sensor (CTS) connector.

    15. Object Number: 1289770 Size: SH
  15. Remove the air cleaner housing bolts.
  16. Remove the air cleaner housing.
  17. Remove the right front wheel. Refer to Tire and Wheel Removal and Installation .
  18. Remove the right front wheel well splash shield.
  19. Install the J 28467-B .
  20. Remove the right engine mount bracket and bolts. Refer to Engine Mount Replacement .

    21. Object Number: 1289772 Size: SH
  21. Disconnect the upper radiator hose at the thermostat housing.
  22. Remove the serpentine accessory drive belt. Refer to Power Steering Pump Belt Replacement .
  23. Remove the crankshaft pulley bolts.
  24. Remove the crankshaft pulley.

    25. Object Number: 1289773 Size: SH
  25. Remove the front timing belt cover bolts.
  26. Remove the front timing belt cover.

    27. Object Number: 1289764 Size: SH
  27. Remove the timing belt. Refer to Timing Belt Replacement .
  28. Disconnect the breather tube at the camshaft cover.
  29. Remove the spark plug cover bolts.
  30. Remove the spark plug cover.
  31. Disconnect the ignition wires from the spark plugs.
  32. Remove the camshaft cover bolts.
  33. Remove the camshaft cover and the camshaft cover gasket.

    34. Object Number: 1289774 Size: SH

    Important: Take extreme care to prevent any scratches, nicks or damage to the camshafts.

  34. While holding the intake camshaft firmly in place, remove the intake camshaft gear bolt.
  35. Remove the intake camshaft gear.
  36. While holding the exhaust camshaft firmly in place, remove the exhaust camshaft gear bolt.
  37. Remove the exhaust camshaft gear.

    38. Object Number: 1289775 Size: SH
  38. Remove the timing belt automatic tensioner bolts.
  39. Remove the timing belt automatic tensioner.

    40. Object Number: 1291155 Size: SH
  40. Remove the timing belt idler pulley bolt and nut.
  41. Remove the timing belt idler pulleys.
  42. Remove the engine mount bolts.
  43. Remove the engine mount.

    44. Object Number: 1289777 Size: SH
  44. Remove the rear timing belt cover bolts.
  45. Remove the rear timing belt cover.

    46. Object Number: 1289778 Size: SH
  46. Remove the exhaust flex pipe retaining nuts at the exhaust manifold studs.
  47. Disconnect all of the necessary vacuum hoses.

    48. Object Number: 1289776 Size: SH
  48. Disconnect the fuel feed line at the fuel rail.
  49. Remove the generator adjusting bracket retaining bolt and the bracket.
  50. Disconnect the coolant hose at the rear cylinder head and ignition coil exhaust gas recirculation (EGR) bracket.
  51. Disconnect the surge tank coolant hose at the throttle body.
  52. Remove the fuel rail assembly. Refer to Fuel Injection Fuel Rail Assembly Replacement .

    53. Object Number: 1289779 Size: SH
  53. Remove the generator-to-intake manifold support bracket bolts at the cylinder head and the intake manifold.
  54. Remove the generator support bracket.
  55. Remove the intake manifold-to-generator strap bracket bolt and loosen the bolt on the generator.
  56. Move the strap clear of the intake manifold.
  57. Remove the charcoal canister purge (CCP) and EGR solenoid bracket bolt and move the bracket clear.

    58. Object Number: 1289780 Size: SH
  58. Disconnect the throttle cable at the throttle body and the intake manifold.
  59. Loosen all of the cylinder head bolts gradually and in the sequence shown.
  60. Remove the cylinder head bolts.
  61. Remove the cylinder head with the intake manifold and the exhaust manifold attached.

    62. Notice: Use extreme care when removing the cylinder head to prevent any engine oil , dirt, or coolant from entering the engine. Damage to the engine could result.

  62. Remove the cylinder head gasket.
  63. Clean the gasket surfaces on the cylinder head and the engine block. Refer to Cylinder Head Cleaning and Inspection .

Installation Procedure

    Object Number: 1289781 Size: SH
  1. Install the cylinder head gasket.
  2. Install the cylinder head with the intake manifold and the exhaust manifold attached.

    3. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the cylinder head bolts.
  4. Tighten the cylinder head bolts gradually and in the sequence shown.

    5. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).


    Object Number: 1289782 Size: SH
  5. Use the J 45059 or the KM-470-B to tighten the bolts another 3 turns of 90 degrees.

    6. Object Number: 1289779 Size: SH
  6. Connect the throttle cable at the throttle body and the intake manifold.
  7. Install the generator-to-intake manifold support bracket.
  8. Install the intake generator-to-manifold support bracket bolts.

    9. Tighten
    Tighten the bolt to the intake manifold to 22 N·m (16 lb ft).

  9. Install the intake manifold support bracket bolt to the generator.

    10. Tighten
    Tighten the bolt at the generator to 22 N·m (16 lb ft).

  10. Connect the surge tank coolant hose at the throttle body.
  11. Connect the coolant hose to the rear cylinder head and ignition coil EGR bracket.

    12. Object Number: 1289776 Size: SH
  12. Connect the fuel feed line at the fuel rail.
  13. Connect the fuel return line at the fuel rail.
  14. Connect all of the necessary vacuum hoses.
  15. Install the fuel rail assembly. Refer to Fuel Injection Fuel Rail Assembly Replacement .

    16. Object Number: 1289777 Size: SH
  16. Install the exhaust flex pipe retaining nuts at the exhaust manifold studs.

    17. Tighten
    Tighten the nuts to 35 N·m (26 lb ft).

  17. Install the rear timing belt cover.
  18. Install the rear timing belt cover bolts.

    19. Tighten
    Tighten the bolts to 7 N·m (62 lb in).

  19. Install the engine mount and the retaining bolts.

    20. Tighten
    Tighten the bolts to 45 N·m (33 lb ft).


    Object Number: 1289775 Size: SH
  20. Install the timing belt automatic tensioner.
  21. Install the timing belt automatic tensioner bolt.

    22. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).

  22. Install the timing belt idler pulleys.
  23. Install the timing belt idler pulley bolt and nut.

    24. Tighten
    Tighten the bolt to 25 N·m (18 lb ft).


    Object Number: 1289783 Size: SH
  24. Install the camshaft gears with the timing marks at the front.
  25. Insert the guide pin of the intake camshaft into the IN bore.
  26. Insert the guide pin of the exhaust camshaft into the EX bore.

    27. Object Number: 1289774 Size: SH
  27. Install the camshaft gears by counterholding on the hex of the camshaft with an open-ended wrench.
  28. Install the camshaft gear with a new bolt to the camshaft.

    29. Tighten
    Tighten the bolt to 50 N·m (37 lb ft). Turn the bolt another 60 degrees and 15 degrees using the angular torque gage.

  29. While holding the exhaust firmly in place, install the exhaust camshaft gear bolt.

    30. Tighten
    Tighten the bolt to 50 N·m (37 lb ft). Turn the bolt another 60 degrees and 15 degrees using the J 45059 or the KM-470-B .


    Object Number: 1289765 Size: SH
  30. Apply a small amount of gasket sealant to the corners of the front camshaft caps and to the top of the rear camshaft cover-to-cylinder head seal.
  31. Install the camshaft cover and the camshaft cover gasket.
  32. Install the camshaft cover washers.
  33. Install the camshaft cover bolts.

    34. Tighten
    Tighten the bolts to 8 N·m (71 lb in).


    Object Number: 1289784 Size: SH
  34. Connect the ignition wires to the spark plugs.
  35. Install the spark plug cover.
  36. Install the spark plug cover bolts.

    37. Tighten
    Tighten the bolts to 8 N·m (71 lb in).

  37. Connect the breather tube to the camshaft cover.
  38. Align the timing marks on the camshaft gears to the notches on the camshaft cover, using the intake gear mark (1), for the intake gear and the exhaust gear mark (2) for the exhaust gear.

    39. Object Number: 1289785 Size: SH
  39. Align the mark on the crankshaft gear with the notch at the bottom of the rear timing belt cover.

    40. Object Number: 1291155 Size: SH
  40. Install the timing belt.
  41. Check and adjust the timing belt tension. Refer to Timing Belt Inspection .

    42. Object Number: 1289773 Size: SH
  42. Install the front timing belt cover.
  43. Install the front timing belt cover bolts.

    44. Tighten
    Tighten the bolts to 6 N·m (53 lb in).

  44. Install the crankshaft pulley.
  45. Install the crankshaft pulley bolts.

    46. Tighten
    Tighten the bolts to 12 N·m (106 lb in).


    Object Number: 1289770 Size: SH
  46. Install the right engine mount bracket and retaining bolts. Refer to Engine Mount Replacement .

    47. Tighten
    Tighten the bolts to 55 N·m (41 lb ft).

  47. Remove the J 28467-B .
  48. Install the serpentine accessory drive belt. Refer to Power Steering Pump Belt Replacement .
  49. Connect the upper radiator hose to the thermostat housing.
  50. Install the right front wheel well splash shield.
  51. Install the right front wheel. Refer to Tire and Wheel Removal and Installation .

    52. Object Number: 1289768 Size: SH
  52. Install the air cleaner housing.
  53. Install the air cleaner housing bolts.

    54. Tighten
    Tighten the bolts to 10 N·m (89 lb in).

  54. Connect the air cleaner outlet hose to the throttle body.
  55. Connect the breather tube to the camshaft cover.
  56. Connect the IAT sensor connector.

    57. Object Number: 1289769 Size: SH
  57. Connect the CTS connector.
  58. Connect the ECT sensor connector.
  59. Connect the IAC valve connector.
  60. Connect the TP sensor connector
  61. Install the CCP and the EGR solenoid bracket bolt.

    62. Tighten
    Tighten the bolt to 5 N·m (44 lb in).


    Object Number: 1289766 Size: SH
  62. Connect the DIS coil connector.
  63. Connect the O2S connector, if equipped.
  64. Connect the ECM ground terminal.
  65. Install the fuel pump fuse.
  66. Connect the negative battery ground cable.
  67. Refill the engine cooling system. Refer to Cooling System Draining and Filling .