CYLINDER HEAD INSPECTION


  1. INSPECT CYLINDER HEAD FOR WARPAGE


    1. A01ETR2E07
      Text in Illustration
      *a Cylinder Block Side
      *b Intake Manifold Side
      *c Exhaust Manifold Side

      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


    1. A01EWVU

      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 Click here.

    2. A01EVW5

      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 0.080 to 0.135 mm (0.00315 to 0.00532 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.

    2. Place the camshafts on the cylinder head.

    3. A01EUEWE04
      Text in Illustration
      *1 Plastigage

      Lay a strip of Plastigage across each of the camshaft journals.

    4. Install the bearing caps Click here.

      Note

      Do not turn the camshaft.

    5. Remove the bearing caps Click here.

    6. A01ETC4E02
      Text in Illustration
      *1 Plastigage

      Measure the Plastigage at its widest point.

      Standard Oil Clearance
      Item Specified Condition
      Intake No. 1 journal 0.007 to 0.038 mm (0.000276 to 0.00150 in.)
      Exhaust No. 1 journal 0.040 to 0.079 mm (0.00157 to 0.00311 in.)
      Other journals 0.025 to 0.062 mm (0.000984 to 0.00244 in.)
      Maximum Oil Clearance
      Item Specified Condition
      Intake No. 1 journal 0.070 mm (0.00276 in.)
      Other journals 0.100 mm (0.00394 in.)

      Note

      Completely remove the Plastigage after the inspection.


      • If the oil clearance is greater than the maximum, replace the camshaft. If necessary, replace the cylinder head.

      • If the oil clearance on the camshaft No. 1 journal is greater than the maximum, choose a new bearing and install it.


      1. A01EXF0E08
        Text in Illustration
        *a Number Mark

        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


    1. A01EV6J

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

      Free length
      47.43 mm (1.867 in.)

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

    2. A01EUPIE12
      Text in Illustration
      *a Deviation

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

      Maximum deviation
      1.6 mm (0.0630 in.)

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

  6. INSPECT INTAKE VALVE


    1. A01EXEE

      Using a gasket scraper, scrape off any carbon on the valve head.

    2. Using a wire brush, thoroughly clean the intake valve.

    3. A01ETPRE04
      Text in Illustration
      *a Overall Length

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

    4. A01EY08

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

      Standard 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.

    5. A01EVWSE04
      Text in Illustration
      *a Margin Thickness

      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 intake valve.

  7. INSPECT EXHAUST VALVE


    1. A01EXEE

      Using a gasket scraper, scrape off any carbon on the valve head.

    2. Using a wire brush, thoroughly clean the exhaust valve.

    3. A01EUWIE04
      Text in Illustration
      *a Overall Length

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

    4. A01EWP8

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

      Standard 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.

    5. A01ETX5E04
      Text in Illustration
      *a Margin Thickness

      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 exhaust valve.

  8. INSPECT INTAKE VALVE GUIDE BUSH


    1. A01EVIJ

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

      Standard bushing inside diameter
      5.510 to 5.530 mm (0.2169 to 0.2177 in.)

    2. Subtract the valve stem diameter measurement from the intake valve guide bush inside diameter measurement.

      Standard oil clearance
      0.025 to 0.060 mm (0.000984 to 0.00236 in.)
      Maximum oil clearance
      0.080 mm (0.00315 in.)

      If the clearance is greater than the maximum, replace the intake valve and intake valve guide bush.

  9. INSPECT EXHAUST VALVE GUIDE BUSH


    1. A01EWPE

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

      Standard bushing inside diameter
      5.510 to 5.530 mm (0.2169 to 0.2177 in.)

    2. Subtract the valve stem diameter measurement from the guide bushing inside diameter measurement.

      Standard oil clearance
      0.030 to 0.065 mm (0.00118 to 0.00256 in.)
      Maximum oil clearance
      0.10 mm (0.00394 in.)

      If the clearance is greater than the maximum, replace the exhaust valve and exhaust valve guide bush.

  10. INSPECT VALVE LIFTER


    1. A01EUP7E01

      Using a micrometer, measure the lifter diameter.

      Standard lifter diameter
      30.966 to 30.976 mm (1.2191 to 1.2195 in.)
    2. A01EYUT

      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.)

    3. 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
      0.070 mm (0.00276 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


    1. A01EW62E07
      Text in Illustration
      *a Measurement Length

      Using a vernier caliper, measure the length of the cylinder head set 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 cylinder head set bolt length is greater than the maximum, replace the cylinder head set bolt.