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For 1990-2009 cars only

Cylinder Head Assemble LY7

Special Tools

    • EN-46116 Valve Stem Seal Remover/Installer
    • EN-46117 Valve Stem Key Remover/Installer
    • EN-46119 Off-Vehicle Valve Spring Compressor Adapter
    • EN-46122 Camshaft Position Actuator Check-Ball Valve Remover/Installer
    • J 8062 Valve Spring Compressor - Head Off
        For equivalent regional tools, refer to Special Tools.

    Object Number: 2164001  Size: SH
  1. Use lubricant included with EN-46122 remover/installer to lubricate outside of new check valve (1).
  2. With the check ball end of the check valve facing UP, away from the head, insert the NEW check valve into the check valve bore in the cylinder head.

  3. Object Number: 2164004  Size: SH
  4. Place collar EN-46122-2 (1) over the new check valve with the slightly-larger inside diameter of the collar DOWN toward the cylinder head.
  5. Using the driver EN-46122-1 (2), lightly tap the new check valve into place until the driver stops against the top of the collar.

  6. Object Number: 1492613  Size: SH
  7. Inspect the camshaft position actuator oil feed check valves in order to ensure they are properly installed in the cylinder head. The camshaft position actuator oil feed check valve should be flush to 2 mm (0.0787 in) below the cylinder head deck surface (a).
  8. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1210901  Size: SH
  9. Install the cylinder head coolant threaded plugs and tighten to 31 N·m (23 lb ft).

  10. Object Number: 1210891  Size: SH
  11. Install the NEW cylinder head oil gallery expansion plugs.

  12. Object Number: 1210887  Size: SH
  13. Place the valve stem oil seals onto the guides.
  14. Note: NEVER reuse a valve stem oil seal. Always use new seals when assembling the cylinder head.

  15. Mount a new valve stem oil seal using the EN-46116 seal remover/installer .
  16. Note: Force should only be applied to the valve spring contact area of the new valve stem oil seal during installation.

  17. Push and twist the valve stem oil seal into position on the valve guide until the seal positively locks on the guide using the EN-46116 seal remover/installer .
  18. Lubricate the valve stem and valve guide ID with clean engine oil GM P/N 12345501 (Canadian P/N 992704) or equivalent.

  19. Object Number: 1210884  Size: SH

    Note: The valve stem oil seal must not come loose from the valve guide when the valve is installed.

  20. Insert the valve into the valve guide until it bottoms on the valve seat.

  21. Object Number: 1210879  Size: SH
  22. Position the valve spring on the spring seat.
  23. Place the valve spring retainer onto the valve spring.

  24. Object Number: 1210825  Size: SH

    Warning: Compressed valve springs have high tension against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.

    Caution: Do not compress the valve springs less than 24.0 mm (0.943 in). Contact between the valve spring retainer and the valve stem oil seal can cause potential valve stem oil seal damage.

  25. Compress the valve spring using the J 8062 compressor - head off and the EN-46119 adapter .

  26. Object Number: 1210911  Size: SH

    Note: Ensure proper directional placement of valve keepers in the EN-46117 key remover/installer . The valve keepers must be installed with the tapered end towards the valve stem seal.

  27. With the spring compressed, install the valve keepers into the J 8062 compressor - head off .

  28. Object Number: 1210829  Size: SH
  29. Place the keepers into position by pushing the tool downward and releasing tension on the EN-46119 adapter and the J 8062 compressor - head off .
  30. Verify that the valve keepers are installed by placing a rag over the valve tip and tapping with a dead-blow hammer. The valve keepers and the spring should remain in place.

Cylinder Head Assemble LCS

Special Tools

    • EN 46116 Valve Stem Seal Remover/Installer
    • EN 46117 Valve Stem Key Remover/Installer
    • EN 46119 Off-Vehicle Valve Spring Compressor Adapter
    • EN-46122 Camshaft Position Actuator Check-Ball Valve Remover/Installer
    • J 8062 Valve Spring Compressor - Head Off
        For equivalent regional tools, refer to Special Tools.

    Object Number: 2164001  Size: SH
  1. Use lubricant included with EN-46122 remover/installer to lubricate outside of new check valve (1).
  2. With the check ball end of the check valve facing UP, away from the head, insert the NEW check valve into the check valve bore in the cylinder head.

  3. Object Number: 2164004  Size: SH
  4. Place collar EN-46122-2 (1) over the new check valve with the slightly-larger inside diameter of the collar DOWN toward the cylinder head.
  5. Using the driver EN-46122-1 (2), lightly tap the new check valve into place until the driver stops against the top of the collar.

  6. Object Number: 1492613  Size: SH
  7. Inspect the camshaft position actuator oil feed check valves in order to ensure they are properly installed in the cylinder head. The camshaft position actuator oil feed check valve should be flush to 2 mm (0.0787 in) below the cylinder head deck surface (a).
  8. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1977967  Size: SH
  9. Install the cylinder head coolant threaded plugs and tighten to 31 N·m (23 lb ft).

  10. Object Number: 1977963  Size: SH
  11. Install the NEW cylinder head oil gallery expansion plugs.

  12. Object Number: 1977962  Size: SH
  13. Place the valve stem oil seals onto the guides.
  14. Note: NEVER reuse a valve stem oil seal. Always use new seals when assembling the cylinder head.

  15. Mount a new valve stem oil seal using the EN 46116 remover/installer .
  16. Note: Force should only be applied to the valve spring contact area of the new valve stem oil seal during installation.

  17. Push and twist the valve stem oil seal into position on the valve guide until the seal positively locks on the guide using the EN 46116 remover/installer .
  18. Lubricate the valve stem and valve guide ID with clean engine oil GM P/N 12345501 (Canadian P/N 992704) or equivalent.

  19. Object Number: 1977960  Size: SH

    Note: The valve stem oil seal must not come loose from the valve guide when the valve is installed.

  20. Insert the valve into the valve guide until it bottoms on the valve seat.

  21. Object Number: 1977958  Size: SH
  22. Position the valve spring on the spring seat.
  23. Place the valve spring retainer onto the valve spring.

  24. Object Number: 1977952  Size: SH

    Warning: Compressed valve springs have high tension against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.

    Caution: Do not compress the valve springs less than 24.0 mm (0.943 in). Contact between the valve spring retainer and the valve stem oil seal can cause potential valve stem oil seal damage.

  25. Compress the valve spring using the J 8062 compressor and the EN 46119 adapter .

  26. Object Number: 1210911  Size: SH

    Note: Ensure proper directional placement of valve keepers in the EN 46117 remover/installer . The valve keepers must be installed with the tapered end towards the valve stem seal.

  27. With the spring compressed, install the valve keepers into the EN 46117 remover/installer .

  28. Object Number: 1977949  Size: SH
  29. Place the keepers into position by pushing the tool downward and releasing tension on the EN 46119 adapter and the J 8062 compressor .
  30. Verify that the valve keepers are installed by placing a rag over the valve tip and tapping with a dead-blow hammer.

  31. Object Number: 1977948  Size: SH
  32. Install the engine coolant temperature (ECT) sensor. - LH Cylinder Head and tighten the ECT sensor to 30 N·m (22 lb ft).
  33. Install the fuel rail with injectors into the cylinder head evenly.
  34. Hand tighten the two outer fuel rail bolts to seat the injector in the injector bores.
  35. Start and hand tighten the remaining fuel rail bolts.
  36. 22.1. Tighten the fuel rail bolts in sequence to 22 N·m (16 lb ft).
    22.2. Tighten the fuel rail bolts in sequence a second time to 22 N·m (16 lb ft).

    Object Number: 1977944  Size: SH
  37. Lubricate the high pressure fuel pump cylinder head bore with 5W30 engine oil.
  38. Note: Ensure that the high pressure fuel pump roller lifter is oriented properly, the camshaft is at base circle and the number 1 piston is at top dead center (TDC) on the exhaust stroke. The distance from the mounting flange surface to the camshaft at base circle should be 52 mm (2.05 in).

  39. Lubricate the high pressure fuel pump roller lifter with 5W30 engine oil and install into the cylinder head bore.

  40. Object Number: 1977940  Size: SH
  41. Install a NEW high pressure fuel pressure fuel pump gasket.
  42. Install a NEW high pressure fuel pump O-ring.
  43. Note: Ensure the plastic bolt retainers are installed in the high pressure fuel pump mounting holes before installing.

  44. Install the high pressure fuel pump.
  45. Caution: Alternately hand-tighten the fuel pump bolts one turn at a time until the pump is fully seated. Trying to draw down the pump without even side-to-side tightening may result in pump plunger damage.

  46. Start and hand-tighten the high pressure fuel pump bolts evenly and tighten the high pressure fuel pump bolts evenly to 15 N·m (11 lb ft).

  47. Object Number: 1977939  Size: SH
  48. Install and hand-tighten both ends of the NEW high pressure fuel line and tighten the high pressure fuel line fitting nuts to 30 N·m (22 lb ft).