Cylinder Head Installation

Special Tools

• EN-301  Measurement Bridge
• GE-7872  Magnetic Base Dial Indicator

For equivalent regional tools, refer to Special Tools .

1. Clean the sealing surfaces.
   CAUTION: 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.
   NOTE:

   • Do not re-use the cylinder head bolts. 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.
2. Inspect the flatness of cylinder head and cylinder block sealing surfaces.
   NOTE: Ensure that the cylinder head and the cylinder block sealing surfaces are clear of oil, grease and old gasket material.
3. Position the piston for the measurement in TDC. Measure with the piston projection using the GE-7872  indicator (1).
   Fig 1: Indicator

   Courtesy of GENERAL MOTORS COMPANY
4. Install a cylinder head gasket with the correct thickness. Refer to Cylinder Head Gasket Selection Specifications .
5. Measure the piston overhang of all pistons and compare with the identification on the cylinder head gasket (1).
   Fig 2: Cylinder Head Gasket Selection Specifications

   Courtesy of GENERAL MOTORS COMPANY
   NOTE: The largest measured piston overhang value is determining for the choice of the cylinder head gasket.
   1. Piston overhang 0.110 mm - 0.230 mm (0.0043 in - 0.0090 in), choose cylinder head gasket without holes.
   2. Piston overhang 0.231 mm - 0.330 mm (0.0091 in - 0.0130 in), choose cylinder head gasket with one hole.
   3. Piston overhang 0.331 mm - 0.425 mm (0.0131 in - 0.0167 in), choose cylinder head gasket with two holes.
6. Install the NEW cylinder head to block gasket (2) at the engine block (3).
   Fig 3: Cylinder Head Gasket

   Courtesy of GENERAL MOTORS COMPANY
   NOTE: Do NOT use any sealing material.
7. Install the cylinder head.
8. Install the 10 NEW cylinder head bolts.
   Fig 4: Cylinder Head Bolts

   Courtesy of GENERAL MOTORS COMPANY
   CAUTION: Refer to Fastener Caution .
   CAUTION: Refer to Torque-to-Yield Fastener Caution .
9. Tighten the 10 NEW cylinder head bolts in following order:
   1. First pass in sequence to 20 N.m (15 lb ft).
      NOTE: The following tightening order applies to ribe cylinder head bolts.
   2. Second pass in sequence to 65 N.m (48 lb ft).
   3. Third pass in sequence to an additional 90 degrees using the EN-45059  meter.
   4. Fourth pass in sequence to an additional 90 degrees using the EN-45059  meter.
   5. Fifth pass in sequence to an additional 90 degrees using the EN-45059  meter.
   1. First pass in sequence to 20 N.m (15 lb ft).
      NOTE: The following tightening order applies to TORX® T60 cylinder head bolts.
   2. Second pass in sequence to 65 N.m (48 lb ft).
   3. Third pass in sequence to an additional 90 degrees, using the EN-45059  meter.
   4. Fourth pass in sequence to an additional 90 degrees, using the EN-45059  meter.
   5. Fifth pass in sequence to an additional 90 degrees, using the EN-45059  meter.
   6. Sixth pass in sequence to an additional 90 degrees, using the EN-45059  meter.