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Cylinder Head Installation - Left Side L98, LS2

Tools Required

    • J 42385-100 Thread Repair Kit
    • J 45059 Angle Meter

    Object Number: 1950907  Size: SH

    Important: Make sure the locating sleeves (2) are correctly installed to the maximum height (A) of 8.3 mm (0.33 in).

  1. Install the locating sleeves (2) into the cylinder block  (1).

  2. Object Number: 1950906  Size: SH

    Important: The cylinder head gasket (3) will fit on either side of the engine. Make sure the tab on the cylinder head gasket (1) is located towards the front half point and the stamping FRONT on the cylinder head gasket (2) is facing the front of the engine.

    Important: Do not use any type of sealant on the cylinder head gasket (3), unless specified.

  3. Install the NEW cylinder head gasket (1) correctly over the locating sleeves.

  4. Object Number: 1950904  Size: SH
  5. Install the cylinder head (3) onto the locating pins and the gasket.
  6. Install the NEW cylinder head bolts (1,2).
  7. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1950899  Size: SH
  8. Tighten the cylinder head bolts.
  9. Tighten

        • First Pass: Tighten the M11 cylinder head bolts (1-10) in sequence to 30 N·m (22 lb ft).
        • Second Pass: Tighten the M11 cylinder head bolts (1-10) in sequence to 90  degrees using the J 45059 .
        • Final Pass: Tighten the M11 cylinder head bolts (1-10) in sequence to 70 degrees using the J 45059 .
        • Tighten the M8 cylinder head bolts (11-15) to 30 N·m (22 lb ft). Begin with the centre bolt (11) and alternating side-to-side, work outward tightening all of the bolts.

Cylinder Head Installation - Left Side LS3

Tools Required

    • J 42385-100 Thread Repair Kit
    • J 45059 Angle Meter

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


    Object Number: 1408869  Size: SH

    Notice: Clean all dirt, debris, and coolant from the engine block cylinder head bolt holes. Failure to remove all foreign material may result in damaged threads, improperly tightened fasteners or damage to components.

    Important: 

       • Do not use the cylinder head bolts again. Install NEW cylinder head bolts during assembly.
       • Do not use any type of sealant on the cylinder head gasket, unless specified.
       • The cylinder head gaskets must be installed in the proper direction and position.

  1. Clean the engine block cylinder head bolt holes, if required.
  2. Thread repair tool J 42385-107 may be used to clean the threads of old threadlocking material.

  3. Spray cleaner into the hole.
  4. Clean the cylinder head bolt holes with compressed air.
  5. Install the cylinder head locating pins (230).

  6. Object Number: 1481465  Size: SH
  7. Inspect the locating pins for proper installation.

  8. Object Number: 1548586  Size: SH
  9. Inspect the displacement markings on the gasket for proper usage.

  10. Object Number: 1408869  Size: SH
  11. Install the NEW cylinder head gasket (217) onto the locating pins.

  12. Object Number: 1408868  Size: SH
  13. Install the cylinder head (218) onto the locating pins and the gasket.
  14. Install the NEW cylinder head bolts (220, 221).
  15. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 260150  Size: SH
  16. Tighten the cylinder head bolts.
  17. Tighten

    1. Tighten the M11 cylinder head bolts (1-10) a first pass in sequence to 30 N·m (22 lb ft).
    2. Tighten the M11 cylinder head bolts (1-10) a second pass in sequence to 90  degrees using the J 45059 .
    3. Tighten the M11 cylinder head bolts (1-10) a final pass in sequence to 70 degrees using the J 45059 .
    4. Tighten the M8 cylinder head bolts (11-15) to 30 N·m (22 lb ft). Begin with the center bolt (11) and alternating side-to-side, work outward tightening all of the bolts.