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Inspection [11/2017 - ]: Procedure

  1. INSPECT CYLINDER HEAD LH 
    1. Using a precision straightedge and feeler gauge, check the surfaces which contact the cylinder block sub-assembly and manifolds for warpage.
      GTY779041Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Intake Manifold Side *b Bottom Side
      *c Exhaust Manifold Side - -

      Standard Warpage

      Item Specified Condition
      Bottom Side 0.05 mm (0.00197 in.)
      Exhaust Manifold Side 0.08 mm (0.00315 in.)
      Intake Manifold Side 0.08 mm (0.00315 in.)

      Maximum Warpage

      0.10 mm (0.00394 in.)

      HINT: 

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

  2. INSPECT CYLINDER HEAD FOR CRACKS 
    1. Using a dye penetrant, check the intake ports, exhaust ports and bottom surface of the cylinder head LH for cracks.

      HINT: 

      If cracks are found, replace the cylinder head LH.

  3. INSPECT INTAKE VALVE 
    1. 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.)

      HINT: 

      If the valve stem diameter is not as specified, check the intake valve guide bush oil clearance.

    2. Using a vernier caliper, measure the valve head margin thickness.
      GTY776234Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Margin Thickness

      Standard Margin Thickness

      1.0 mm (0.0394 in.)

      Minimum Margin Thickness

      0.5 mm (0.0197 in.)

      HINT: 

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

    3. Using a vernier caliper, measure the overall length of the intake valve.

      Standard Overall Length

      105.85 mm (4.17 in.)

      Minimum Overall Length

      105.35 mm (4.15 in.)

      HINT: 

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

  4. INSPECT EXHAUST VALVE 
    1. 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.)

      HINT: 

      If the valve stem diameter is not as specified, check the exhaust valve guide bush oil clearance.

    2. Using a vernier caliper, measure the valve head margin thickness.
      GTY816880Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Margin Thickness

      Standard Margin Thickness

      1.0 mm (0.0394 in.)

      Minimum Margin Thickness

      0.5 mm (0.0197 in.)

      HINT: 

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

    3. Using a vernier caliper, measure the overall length of the exhaust valve.

      Standard Overall Length

      110.40 mm (4.35 in.)

      Minimum Overall Length

      109.90 mm (4.33 in.)

      HINT: 

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

  5. INSPECT INTAKE VALVE SEAT 
    1. Apply a light coat of Prussian blue to the valve face.
    2. Lightly press the valve face against the intake valve seat.
      NOTE:

      Do not rotate the intake valve while pressing it.

    3. Check the valve face and intake valve seat by using the following procedure:
      GTY825210Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Width
      1. If Prussian blue appears 360° around the entire intake valve face, the valve face is concentric.

        HINT: 

        If the valve face is not concentric, replace the intake valve.

      2. If Prussian blue appears 360° around the entire intake valve seat, the intake valve seat and valve face are concentric.

        HINT: 

        If the valve face is not concentric, resurface the intake valve seat.

      3. Measure the width of the contact area of the intake valve seat and valve face.

        Standard Width

        1.1 to 1.5 mm (0.0433 to 0.0591 in.)

  6. INSPECT EXHAUST VALVE SEAT 
    1. Apply a light coat of Prussian blue to the valve face.
    2. Lightly press the valve face against the exhaust valve seat.
      NOTE:

      Do not rotate the exhaust valve while pressing it.

    3. Check the valve face and exhaust valve seat by using the following procedure:
      GTY825209Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Width
      1. If Prussian blue appears 360° around the entire exhaust valve face, the valve face is concentric.

        HINT: 

        If the valve face is not concentric, replace the exhaust valve.

      2. If Prussian blue appears 360° around the entire exhaust valve seat, the exhaust valve seat and valve face are concentric.

        HINT: 

        If the valve face is not concentric, resurface the exhaust valve seat.

      3. Measure the width of the contact area of the exhaust valve seat and valve face.

        Standard Width

        1.3 to 1.7 mm (0.0512 to 0.0669 in.)

  7. INSPECT INNER COMPRESSION SPRING 
    1. Using a vernier caliper, measure the free length of the inner compression spring.
      GTY420347Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Free Length

      54.53 mm (2.15 in.)

      Minimum Free Length

      52.43 mm (2.06 in.)

      HINT: 

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

    2. Using a steel square, measure the deviation of the inner compression spring.
      GTY836393Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a 30 mm (1.18 in.)
      *b Deviation

      Maximum Deviation (Reference)

      1.0 mm (0.0394 in.)

      Maximum Angle (Reference)

      2°

      HINT: 

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

  8. INSPECT VALVE GUIDE BUSH OIL CLEARANCE 
    1. Using a caliper gauge, measure the inside diameter of the valve guide bush.
      GTY401329Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Valve Guide Bush Inside Diameter

      5.51 to 5.53 mm (0.217 to 0.218 in.)

    2. Subtract the valve stem diameter measurement from the valve 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 0.080 mm (0.00315 in.)
      Exhaust 0.085 mm (0.00335 in.)

      HINT: 

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

  9. INSPECT CAMSHAFT THRUST CLEARANCE 
    1. Inspect the camshaft thrust clearance (for Bank 1).
      1. Install the camshaft.

        Refer to PROCEDURE - Step 26

      2. Install the No. 2 camshaft.

        Refer to PROCEDURE - Step 27

      3. Using a dial indicator, measure the thrust clearance while moving each camshaft back and forth.
        GTY417199Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Thrust Clearance

        0.08 to 0.13 mm (0.00315 to 0.00512 in.)

        Maximum Thrust Clearance

        0.15 mm (0.00591 in.)

        HINT: 

        • If the thrust clearance is more than the maximum, replace the camshaft housing sub-assembly.
        • If the thrust surface is damaged, replace the camshaft or No. 2 camshaft.
    2. Inspect the camshaft thrust clearance (for Bank 2).
      1. Install the No. 3 camshaft sub-assembly.

        Refer to PROCEDURE - Step 16

      2. Install the No. 4 camshaft sub-assembly.

        Refer to PROCEDURE - Step 17

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

        Standard Thrust Clearance

        0.08 to 0.13 mm (0.00315 to 0.00512 in.)

        Maximum Thrust Clearance

        0.15 mm (0.00591 in.)

        HINT: 

        • If the thrust clearance is more than the maximum, replace the camshaft housing sub-assembly LH.
        • If the thrust surface is damaged, replace the No. 3 camshaft sub-assembly or No. 4 camshaft sub-assembly.
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