GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2008 🢒 Yukon XL Denali 🢒 Engine 🢒 Engine Mechanical - Hybrid (HP2) 6.0L (LFA) 🢒 Cylinder Head Assemble

Tools Required

J 8062 Valve Spring Compressor - Head Off


    Object Number: 1559870 Size: SH
  1. Clean the cylinder head valve spring shim area.

    2. Important: When using the valves and related components again, install the parts to their original location.

  2. Install the valves (228) into the proper port. Refer to Separating Parts.
  3. Install the valve stem oil seal (222).
  4. Install the valve spring (223).
  5. Install the valve spring cap (224).

    6. Object Number: 260151 Size: SH
  6. Using the J 8062 , compress the valve spring.
  7. Install the valve stem keys.
    8. 7.1. Use grease in order to hold the keys in place and remove the J 8062 .
    7.2. Ensure the keys seat properly in the groove of the valve stem.
    7.3. Tap the end of the valve stem with a plastic face hammer to seat the keys, if necessary.

    Object Number: 64315 Size: SH
  8. Using a ruler, measure the valve spring installed height.

    9. Measure from the base of the valve spring to the top of the valve spring.

    Specification

        • If the installed height exceeds 46.25 mm (1.82 in), install a valve spring shim of approximately 0.5 mm (0.02 in) thick.
        • Do not shim the valve spring to obtain less than the specified height.
        • Do not assemble the components without a spring shim on the cylinder head.
  9. Install the remaining valves, springs, and other components.

    10. Object Number: 1559875 Size: SH
  10. Install sealant GM P/N 12346004 (Canadian P/N 10953480), or equivalent, to the threads of the coolant temperature sensor (725).

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

  11. Install the coolant temperature sensor into the left cylinder head.

    12. Tighten
    Tighten the coolant temperature sensor to 20 N·m (15 lb ft).


    Object Number: 1559878 Size: SH
  12. Install sealant GM P/N 12346004 (Canadian P/N 10953480), or equivalent, to the threads of the cylinder head plug (229).
  13. Install the cylinder head plug to the right cylinder head.

    14. Tighten
    Tighten the cylinder head plug to 20 N·m (15 lb ft).


    Object Number: 1559873 Size: SH
  14. Apply threadlock GM P/N 12345382 (Canadian P/N 10953489), or equivalent, to the sides of the cylinder head plugs (216).
  15. Install the cylinder head plugs into the cylinder head.

    16. A properly installed plug should be installed 2.5 mm (0.1 in) below the end face of the head.


    Object Number: 2046466 Size: SH
  16. Second design applications use a rivet-type plug (1) at the top rear coolant passage of each cylinder head. If service of a leaking plug is required, it is necessary to remove the cylinder head from the engine to properly remove the plug.

    17. Object Number: 1408862 Size: SH
  17. If plug removal is required, install a first design coolant air bleed cover and bolt (312) to complete the repair.