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Inspection [04/2013 - 10/2017]: Procedure

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  1. INSPECT CYLINDER HEAD FOR FLATNESS 
    1. Using a precision straightedge and feeler gauge, measure the warpage of the contact surfaces where the cylinder head contacts the cylinder block sub-assembly intake manifold and exhaust manifold.
      GTY456865Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Cylinder Block Sub-assembly Side *b Intake Side
      *c Exhaust Side -  

      Standard Warpage

      Item Specified Condition
      Cylinder block side 0 to 0.05 mm (0 to 0.00197 in.)
      Intake side 0 to 0.08 mm (0 to 0.00315 in.)
      Exhaust side 0 to 0.08 mm (0 to 0.00315 in.)

      Maximum warpage

      0.10 mm (0.00394 in.)

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

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

      If cracked, replace the cylinder head.

  3. INSPECT INTAKE VALVE 
    1. Using a micrometer, measure the diameter of the valve stem.
      GTY139468Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard valve stem diameter

      5.470 to 5.485 mm (0.215 to 0.216 in.)

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

      See step  8

    2. Using a vernier caliper, measure the valve head margin thickness.
      GTY456387Courtesy 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.)

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

    3. 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.

      GTY460830Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a overall Length
  4. INSPECT EXHAUST VALVE 
    1. Using a micrometer, measure the diameter of the valve stem.
      GTY162200Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard valve stem diameter

      5.465 to 5.480 mm (0.215 to 0.216 in.)

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

      See step  8

    2. Using a vernier caliper, measure the valve head margin thickness.
      GTY465691Courtesy 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.)

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

    3. 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.

      GTY460830Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a overall Length
  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.

    3. Check the intake valve face and intake valve seat by using the following procedure:
      GTY467291Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Width
      1. If Prussian blue appears around the entire valve face, the valve face is circular. If not, replace the intake valve.
      2. If Prussian blue appears around the entire intake valve seat, the valve guide bush and valve face are concentric.

        If not, resurface the intake valve seat.

      3. Check that the intake valve seat contacts the middle of the valve face with the width between 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.

    3. Check the exhaust valve face and exhaust valve seat by using the following procedure:
      GTY467291Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Width
      1. If Prussian blue appears around the entire valve face, the exhaust valve face is circular.

        If not, replace the exhaust valve.

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

        If not, resurface the exhaust valve seat.

      3. Check that the exhaust valve seat contacts the middle of the valve face with the width between 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.
      GTY136256Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard free length

      48.05 mm (1.89 in.)

      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.
      GTY458648Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Deviation

      Maximum deviation

      1.0 mm (0.0394 in.)

      Maximum angle (reference)

      2°

      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.
      GTY104200Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard bush inside diameter

      5.510 to 5.530 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 0.030 to 0.060 mm (0.00118 to 0.00236 in.)
      Exhaust 0.025 to 0.065 mm (0.000984 to 0.00256 in.)

      Maximum Oil Clearance

      Item Specified Condition
      Intake 0.08 mm (0.00315 in.)
      Exhaust 0.01 mm (0.000394 in.)

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

  9. INSPECT CAMSHAFT THRUST CLEARANCE 
    1. Inspect the bank 1 camshaft thrust clearance.
      1. Install the camshaft.

        Refer to PROCEDURE - Step 20

      2. Install the No. 2 camshaft.

        Refer to PROCEDURE - Step 21

      3. Using a dial indicator, measure the camshaft thrust clearance while moving the camshaft and No. 2 camshaft back and forth.
        GTY145635Courtesy 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.)

        If the camshaft thrust clearance is more than the maximum, replace the camshaft housing sub-assembly RH.

        If the thrust surface is damaged, replace the camshaft or No. 2 camshaft.

    2. Inspect the bank 2 camshaft thrust clearance.
      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 the No. 3 camshaft sub-assembly and No. 4 camshaft sub-assembly 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.)

        If the camshaft 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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