Cylinder Head Inspection

Engine Hybrid System. Corolla. Zre142 Aze141
2Az-Fe Engine Mechanical. Corolla. Zre142 Aze141

  1. INSPECT CYLINDER HEAD FOR WARPAGE

  2. INSPECT CYLINDER HEAD FOR CRACKS

  3. INSPECT CAMSHAFT THRUST CLEARANCE

  4. INSPECT CAMSHAFT OIL CLEARANCE

  5. INSPECT INNER COMPRESSION SPRING

  6. INSPECT INTAKE VALVE

  7. INSPECT EXHAUST VALVE

  8. INSPECT INTAKE VALVE GUIDE BUSH

  9. INSPECT EXHAUST VALVE GUIDE BUSH

  10. INSPECT VALVE LIFTER

  11. INSPECT CYLINDER HEAD SET BOLT

Cylinder Head -- Inspection



1. INSPECT CYLINDER HEAD FOR WARPAGE


    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Using a precision straight edge and a feeler gauge, measure the surface contacting the cylinder block and the manifolds for warpage.

    Maximum Warpage:
    Item
    Specified Condition
    Cylinder block side
    0.08 mm (0.00315 in.)
    Intake manifold side
    0.08 mm (0.00315 in.)
    Exhaust manifold side
    0.08 mm (0.00315 in.)
    If the warpage is greater than the maximum, replace the cylinder head.


2. INSPECT CYLINDER HEAD FOR CRACKS


    Corolla. Zre142 Aze141
  1. Using a dye penetrant, check the intake ports, exhaust ports and cylinder surface for cracks.
    If cracked, replace the cylinder head.



3. INSPECT CAMSHAFT THRUST CLEARANCE
  1. Install the camshafts (COROLLA_ZRE142 RM00000224800UX_01_0017.html).



    Corolla. Zre142 Aze141
  1. Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.

    Standard Thrust Clearance:
    Item
    Specified Condition
    Intake
    0.040 to 0.095 mm (0.00157 to 0.00374 in.)
    Exhaust
    0.090 to 0.145 mm (0.00354 to 0.00570 in.)
    Maximum Thrust Clearance:
    Item
    Specified Condition
    Intake
    0.110 mm (0.00433 in.)
    Exhaust
    0.150 mm (0.00591 in.)
    If the thrust clearance is greater than the maximum, replace the cylinder head. If the thrust surface is damaged, replace the camshaft.


4. INSPECT CAMSHAFT OIL CLEARANCE
  1. Clean the bearing caps and camshaft journals.

  1. Place the camshafts on the cylinder head.



    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Lay a strip of Plastigage across each of the camshaft journals.

  1. Install the bearing caps (COROLLA_ZRE142 RM00000224800UX_01_0017.html).

    NOTICE:
    Do not turn the camshaft.
  1. Remove the bearing caps (COROLLA_ZRE142 RM00000224700UX_01_0028.html).



    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Measure the Plastigage at its widest point.

    Standard Oil Clearance:
    Item
    Specified Condition
    Camshaft No. 1 journal bearing mark 1
    0.007 to 0.038 mm (0.000276 to 0.00150 in.)
    Camshaft No. 1 journal bearing mark 2
    0.008 to 0.038 mm (0.000315 to 0.00150 in.)
    Camshaft No. 1 journal bearing mark 3
    0.008 to 0.038 mm (0.000315 to 0.00150 in.)
    Camshaft other journals
    0.025 to 0.062 mm (0.000984 to 0.00244 in.)
    No. 2 camshaft No. 1 journal
    0.040 to 0.072 mm (0.00157 to 0.00283 in.)
    No. 2 camshaft other journals
    0.025 to 0.062 mm (0.000984 to 0.00244 in.)
    Maximum Oil Clearance:
    Item
    Specified Condition
    Intake
    0.070 mm (0.00276 in.)
    Exhaust
    0.100 mm (0.00394 in.)
    NOTICE:
    Completely remove the Plastigage after the inspection.
    1. If the oil clearance is greater than the maximum, replace the camshaft. If necessary, replace the cylinder head.
    2. If the oil clearance on the camshaft No. 1 journal is greater than the maximum, choose a new bearing and install it.



      Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
    1. Check the number mark shown in the illustration.

      Cylinder Head Journal Bore Diameter:
      Mark 1
      Mark 2
      Mark 3
      40.000 to 40.009 mm (1.5748 to 1.5752 in.)
      40.010 to 40.017 mm (1.5752 to 1.5755 in.)
      40.018 to 40.025 mm (1.5755 to 1.5758 in.)
      Standard Bearing Center Wall Thickness:
      Mark 1
      Mark 2
      Mark 3
      2.000 to 2.004 mm (0.0787 to 0.0789 in.)
      2.005 to 2.008 mm (0.0789 to 0.0791 in.)
      2.009 to 2.012 mm (0.0791 to 0.0792 in.)
      Camshaft journal diameter:
      35.971 to 35.985 mm (1.4162 to 1.4167 in.)


5. INSPECT INNER COMPRESSION SPRING


    Corolla. Zre142 Aze141
  1. Using a vernier caliper, measure the free length of the valve spring.

    Free length:
    47.43 mm (1.867 in.)
    If the free length is not as specified, replace the valve spring.


    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Using a steel set square, measure the deviation of the valve spring.

    Maximum deviation:
    1.6 mm (0.063 in.)
    If the deviation is greater than the maximum, replace the valve spring.


6. INSPECT INTAKE VALVE


    Corolla. Zre142 Aze141
  1. Using a gasket scraper, scrape off any carbon on the valve head.



    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Using a vernier caliper, measure the overall length of the valve.

    Standard overall length:
    101.71 mm (4.0043 in.)
    Minimum overall length:
    101.21 mm (3.9846 in.)
    If the overall length is less than the minimum, replace the valve.


    Corolla. Zre142 Aze141
  1. Using a micrometer, measure the diameter of the valve stem.

    Valve stem diameter:
    5.470 to 5.485 mm (0.2154 to 0.2159 in.)
    If the valve stem is not as specified, check the oil clearance.


    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Using a vernier caliper, measure the valve head margin thickness.

    Standard margin thickness:
    1.05 to 1.45 mm (0.0413 to 0.0571 in.)
    Minimum margin thickness:
    0.50 mm (0.0197 in.)
    If the margin thickness is less than the minimum, replace the valve.


7. INSPECT EXHAUST VALVE


    Corolla. Zre142 Aze141
  1. Using a gasket scraper, scrape off any carbon on the valve head.



    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Using a vernier caliper, measure the overall length of the valve.

    Standard overall length:
    101.15 mm (3.9823 in.)
    Minimum overall length:
    100.70 mm (3.9646 in.)
    If the overall length is less than the minimum, replace the valve.


    Corolla. Zre142 Aze141
  1. Using a micrometer, measure the diameter of the valve stem.

    Valve stem diameter:
    5.465 to 5.480 mm (0.2152 to 0.2157 in.)
    If the valve stem is not as specified, check the oil clearance.


    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Using a vernier caliper, measure the valve head margin thickness.

    Standard margin thickness:
    1.20 to 1.60 mm (0.0472 to 0.0630 in.)
    Minimum margin thickness:
    0.50 mm (0.0197 in.)
    If the margin thickness is less than the minimum, replace the valve.


8. INSPECT INTAKE VALVE GUIDE BUSH


    Corolla. Zre142 Aze141
  1. Using a caliper gauge, measure the inside diameter of the guide bush.

    Bushing inside diameter:
    5.510 to 5.530 mm (0.2169 to 0.2177 in.)
  1. Subtract the valve stem diameter measurement from the guide bush inside diameter measurement.

    Standard oil clearance:
    0.025 to 0.060 mm (0.0010 to 0.0024 in.)
    Maximum oil clearance:
    0.090 mm (0.0035 in.)
    If the clearance is greater than the maximum, replace the valve and guide bush.


9. INSPECT EXHAUST VALVE GUIDE BUSH


    Corolla. Zre142 Aze141
  1. Using a caliper gauge, measure the inside diameter of the guide bush.

    Bushing inside diameter:
    5.510 to 5.530 mm (0.2169 to 0.2177 in.)
  1. Subtract the valve stem diameter measurement from the guide bushing inside diameter measurement.

    Standard oil clearance:
    0.030 to 0.065 mm (0.0012 to 0.0026 in.)
    Maximum oil clearance:
    0.095 mm (0.0037 in.)
    If the clearance is greater than the maximum, replace the valve and guide bush.


10. INSPECT VALVE LIFTER


    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Using a micrometer, measure the lifter diameter.

    Lifter diameter:
    30.966 to 30.976 mm (1.2191 to 1.2195 in.)


    Corolla. Zre142 Aze141
  1. Using a caliper gauge, measure the lifter bore diameter of the cylinder head.

    Standard lifter bore diameter:
    31.009 to 31.025 mm (1.2208 to 1.2215 in.)
  1. Subtract the lifter diameter measurement from the lifter bore diameter measurement.

    Standard oil clearance:
    0.033 to 0.059 mm (0.00130 to 0.00232 in.)
    Maximum oil clearance:
    0.079 mm (0.00311 in.)
    If the oil clearance is greater than the maximum, replace the lifter. If necessary, replace the cylinder head.


11. INSPECT CYLINDER HEAD SET BOLT


    Corolla. Zre142 Aze141.2Az-Fe Engine Mechanical.Engine.Cylinder Head  Inspection
  1. Using a vernier caliper, measure the length of the head bolts from the seat to the end.

    Standard bolt length:
    141.3 to 142.7 mm (5.563 to 5.618 in.)
    Maximum bolt length:
    144.2 mm (5.677 in.)
    If the bolt length is greater than the maximum, replace the cylinder head set bolt.