CYLINDER HEAD INSPECTION


  1. INSPECT CYLINDER HEAD SUB-ASSEMBLY

    A01ERIPE03

    1. Using a precision straightedge and feeler gauge, measure the warpage of the surfaces where the cylinder head contacts the cylinder block and manifold.

      Standard Warpage
      Item Specified Condition
      Cylinder head lower side 0.05 mm (0.00197 in.)
      Intake side 0.08 mm (0.00315 in.)
      Exhaust side 0.05 mm (0.00197 in.)
      Maximum warpage
      0.10 mm (0.00394 in.)

      If the warpage is more than the maximum, replace the cylinder head.

    2. A01EOFX

      Using a dye penetrant, check the intake ports, exhaust ports and cylinder surface for cracks.

      If cracked, replace the cylinder head.

  2. INSPECT INTAKE VALVE


    1. A01ENKC

      Using a micrometer, measure the diameter of the valve stem.

      Standard valve stem diameter
      5.470 to 5.485 mm (0.215 to 0.216 in.)

      If the diameter is not as specified, replace the valve and guide bush.

    2. A01EO69E01

      Using a vernier caliper, measure the valve head margin thickness.

      Standard margin thickness
      1.25 mm (0.0492 in.)
      Minimum margin thickness
      0.50 mm (0.0197 in.)

      If the margin thickness is less than the minimum, replace the intake valve.

    3. A01EPXPE01

      Using a vernier caliper, measure the valve overall length.

      Standard overall length
      105.85 mm (4.17 in.)
      Minimum overall length
      105.35 mm (4.15 in.)

      If the overall length is less than the minimum, replace the intake valve.

  3. INSPECT EXHAUST VALVE


    1. A01EN5P

      Using a micrometer, measure the diameter of the valve stem.

      Standard valve stem diameter
      5.465 to 5.480 mm (0.215 to 0.216 in.)

      If the diameter is not as specified, replace the valve and guide bush.

    2. A01EQ9YE01

      Using a vernier caliper, measure the valve head margin thickness.

      Standard margin thickness
      1.4 mm (0.0551 in.)
      Minimum margin thickness
      0.50 mm (0.0197 in.)

      If the margin thickness is less than the minimum, replace the exhaust valve.

    3. A01EQCGE01

      Using a vernier caliper, measure the valve overall length.

      Standard overall length
      110.40 mm (4.35 in.)
      Minimum overall length
      109.90 mm (4.33 in.)

      If the overall length is less than the minimum, replace the exhaust valve.

  4. INSPECT INTAKE VALVE SEAT

    A01ENIRE01

    1. Apply a light coat of Prussian blue to the valve face.

    2. Lightly press the valve face against the valve seat.

      Tech Tips

      Do not rotate the valve while pressing the valve.

    3. Check the valve face and valve seat.


      1. Check that the contact surfaces of the valve seat and valve face are in the middle area of their respective surfaces, with the width between 1.1 and 1.5 mm (0.0433 and 0.0591 in.).

        If not, correct the valve seat.

      2. Check that the contact surfaces of the valve seat and valve face are even around the entire valve seat.

        If not, correct the valve seat.

  5. INSPECT EXHAUST VALVE SEAT

    A01EQATE01

    1. Apply a light coat of Prussian blue to the valve face.

    2. Lightly press the valve face against the valve seat.

      Tech Tips

      Do not rotate the valve while pressing the valve.

    3. Check the valve face and valve seat.


      1. Check that the contact surfaces of the valve seat and valve face are in the middle area of their respective surfaces, with the width between 1.1 and 1.5 mm (0.0433 and 0.0591 in.).

        If not, correct the valve seat.

      2. Check that the contact surfaces of the valve seat and valve face are even around the entire valve seat.

        If not, correct the valve seat.

  6. INSPECT COMPRESSION SPRING


    1. A01ERV6

      Using a vernier caliper, measure the free length of the inner compression spring.

      Standard free length
      49.39 mm (1.94 in.)

      If the free length is not as specified, replace the spring.

    2. A01EMYTE02

      Using a steel square, measure the deviation of the inner compression spring.

      Maximum deviation
      1.0 mm (0.0394 in.)
      Maximum angle (reference)

      If the deviation is more than the maximum, replace the spring.

  7. INSPECT VALVE GUIDE BUSH OIL CLEARANCE

    A01EORR

    1. Using a caliper gauge, measure the inside diameter of the guide bush.

      Standard bush inside diameter
      5.51 to 5.53 mm (0.217 to 0.218 in.)
    2. Subtract the valve stem diameter measurement from the guide bush inside diameter measurement.

      Standard Oil Clearance
      Item Specified Condition
      Intake 0.025 to 0.060 mm (0.000984 to 0.00236 in.)
      Exhaust 0.030 to 0.065 mm (0.00118 to 0.00256 in.)
      Maximum Oil Clearance
      Item Specified Condition
      Intake 0.08 mm (0.00315 in.)
      Exhaust 0.10 mm (0.00394 in.)

      If the oil clearance is more than the maximum, replace the valve and guide bush.

  8. INSPECT CAMSHAFT THRUST CLEARANCE


    1. Inspect the bank 1 camshafts.


      1. Install the bank 1 camshafts.

      2. A01EPZ4

        Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.

        Standard thrust clearance
        0.08 to 0.135 mm (0.00315 to 0.00531 in.)
        Maximum thrust clearance
        0.15 mm (0.00591 in.)

        If the thrust clearance is more than the maximum, replace the camshaft housing. If the thrust surface is damaged, replace the camshaft.

    2. Inspect the bank 2 camshafts.


      1. Install the bank 2 camshafts.

      2. Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.

        Standard thrust clearance
        0.08 to 0.135 mm (0.00315 to 0.00531 in.)
        Maximum thrust clearance
        0.15 mm (0.00591 in.)

        If the thrust clearance is more than the maximum, replace the camshaft housing. If the thrust surface is damaged, replace the camshaft.