GM Service Manual Online
For 1990-2009 cars only

Special Tools

EN-46105 Camshaft Locking Tool

Removal Procedure


    Object Number: 1796633  Size: SH
  1. Remove the bank 1 cylinder head cover. Refer to Camshaft Cover Replacement - Right Side.
  2. Remove the bank 1 cylinder head camshaft position actuators. Refer to Camshaft Position Actuator Replacement - Bank 1 (Right Side) Exhaust and Camshaft Position Actuator Replacement - Bank 1 (Right Side) Intake.
  3. Note: EN-46105 tool was installed as part of the bank 1 cylinder head camshaft position actuator removal procedure.

  4. Remove the EN-46105 tool  (1) from the bank 1 cylinder head camshafts (2).

  5. Object Number: 1797497  Size: SH
  6. Observe the markings (1) on the bearing caps. Each bearing cap is marked to identify its location. The markings have the following meanings:
  7. • The raised feature must always be oriented toward the center of the cylinder head.
    • An I indicates the intake camshaft.
    • An E indicates the exhaust camshaft.
    • The number indicates the journal position from the front of the engine.

    Object Number: 1797587  Size: SH
  8. Remove the camshaft bearing cap bolts (1) and caps (2).

  9. Object Number: 1797588  Size: SH
  10. Remove the camshafts (1).
  11. Clean the camshaft in solvent and dry it with compressed air.
  12. Inspect the camshaft. Refer to Camshaft Cleaning and Inspection.

Installation Procedure


    Object Number: 1797631  Size: SH
  1. Ensure the camshaft sealing rings (1) are in place in the camshaft grooves.

  2. Object Number: 1797640  Size: SH
  3. Select the correct camshaft for the particular installation location. ID markings are on the rear end of each camshaft. The ID markings are defined as follows:
  4. • The first five digits refer to the date and time of production.
    • Example = 3L18H
    • Digits six through nine refer to engine production code.
    • LY7 = Alloytec190 engine
    • The last two digits refer to position:
    • LI = bank 2 intake
    • LE = bank 2 exhaust
    • RI = bank 1 intake
    • RE = bank 1 exhaust

    Object Number: 1797643  Size: SH
  5. Apply a liberal amount of engine oil to the camshaft (1) journals and the bank 1 cylinder head camshaft carriers (2).

  6. Object Number: 1797588  Size: SH
  7. Apply a liberal amount of engine oil to the camshaft (1) journals and the bank 1 cylinder head camshaft carriers (2).

  8. Object Number: 1796478  Size: SH
  9. Ensure the camshaft lobes are in the neutral position with the flats on the back of the camshafts up and parallel (1) with the bank 1 cylinder head cylinder head cover rail (2).
  10. Ensure the marks on the bank 1 exhaust camshaft position actuator and timing chain, made prior to the disassemble operation are aligned.
  11. Ensure the marks on the bank 1 intake camshaft position actuator and timing chain, made prior to the disassemble operation are aligned.

  12. Object Number: 1797497  Size: SH
  13. Observe the markings on the bank 1 cylinder head camshaft bearing caps. Each bearing cap is marked (1) to identify its location. The markings have the following meanings:
  14. • The raised feature must always be oriented toward the center of the cylinder head.
    • The I indicates the intake camshaft.
    • The E indicates the exhaust camshaft.
    • The number 1, 3, 5 indicates the cylinder position from the front of the engine.
  15. Apply a liberal amount of engine oil to the camshaft bearing caps.

  16. Object Number: 1797587  Size: SH
  17. Apply a liberal amount of engine oil to the camshaft bearing caps.
  18. Install the remaining bearing caps (2) with their orientation mark toward the center of the cylinder head.
  19. Hand starts all the camshaft bearing cap bolts (1).
  20. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1797654  Size: SH
  21. Install the camshaft bearing cap bolts and tighten to 10 N·m (89 lb in).
  22. Loosen the center intake camshaft bearing cap bolts 1 and 2, and the center exhaust camshaft bearing cap bolts 3 and 4.
  23. Retighten the center camshaft bearing cap bolts 1, 2, 3 and 4 to 10 N·m (89 lb in).
  24. Install the bank 1 cylinder head camshaft position actuators.