GM Service Manual Online
For 1990-2009 cars only

Special Tools

J 45059 Angle Meter


    Object Number: 470992  Size: SH

    Caution: Do not use a sealant or adhesive when installing this component. Use of a sealant or adhesive can cause improper sealing. A component that is not sealed properly can leak leading to extensive engine damage.

  1. Place the cylinder head gasket in position over the cylinder head locating pins.

  2. Object Number: 470991  Size: SH

    Note: Guide the cylinder head carefully into place over the locating pins and the cylinder head gasket.

  3. Install the cylinder head to the block.

  4. Object Number: 1309992  Size: SH

    Caution: Do not reuse the cylinder head bolts. NEW cylinder head bolts must be used. The cylinder head bolts are torque-to-yield bolts and cannot be reused once the initial torque is applied. During the initial torque of the cylinder head bolt the cylinder head bolt is stretched to achieve proper clamp load. Proper clamp load will not be achieved if a used cylinder head bolt is torqued again. A stretched cylinder head bolt can also break when torqued. Failure to replace the used cylinder head bolts with NEW cylinder head bolts can lead to improper clamp loads and extensive engine damage.

    Note: The sealer must be applied to a minimum of 8 threads, starting at the point of the cylinder head bolt.

  5. If not pre-applied to the new cylinder head bolts (227, 228, 229), apply sealer GM P/N 12346004 (Canadian P/N 10953480), or equivalent, to the cylinder head bolts. Refer to Adhesives, Fluids, Lubricants, and Sealers.
  6. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 470987  Size: SH

    Caution: Do not reuse a cylinder head gasket once the initial clamping loads are applied. The initial tightening sequence procedure of the cylinder head bolts compresses the cylinder head gasket. If any bolt must be loosened once the initial sequence is started the cylinder head gasket must be replaced. Failure to replace the cylinder head gasket can lead to cylinder head bolt breakage or cylinder head gasket failure. A broken cylinder head bolt or failed cylinder head gasket can lead to extensive engine damage.

    Caution: The cylinder head bolt tightening sequence must be followed. The final angle tightening sequence of the cylinder head bolts varies depending on the length of the cylinder head bolt. Failure to angle tighten the specific length bolt the proper number of degrees can lead to cylinder head bolt failure or improper clamping load of the cylinder head gasket. Cylinder head bolt or cylinder head gasket failure can lead to extensive engine damage.

    Note: The long bolts are used in locations 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16 and 17. The medium length bolts are used in locations 15 and 18. The short bolts are used in locations 4, 5, 12 and 13.

  7. Install the cylinder head bolts.
  8. 4.1. Tighten the bolts (1-18) a first pass in sequence to 30 N·m (22 lb ft).
    4.2. Tighten the bolts (1-18) a second pass in sequence to 30 N·m (22 lb ft), then an additional 120 degrees, using the J 45059 meter .
    4.3. Tighten the bolts, 1, 2, 3, 6, 7, 8, 9, 10, 11, 14, 16, 17, an additional 60 degrees, bolts 15 and 18 an additional 45 degrees, and bolts, 4, 5, 12, 13, an additional 30 degrees a final pass in sequence, using the J 45059 meter .