CYLINDER HEAD > INSPECTION

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1. INSPECT CYLINDER HEAD FOR FLATNESS


    A198667E04

  1. Using a precision straightedge and a feeler gauge, measure the surfaces that contact the cylinder block and the manifolds for warpage.
    Text in Illustration 
    *a
    		Cylinder Block Side
    *b
    		Intake Manifold Side
    *c
    		Exhaust Manifold Side

    Maximum Warpage:
    Item
    		Specified Condition
    Cylinder block side
    		0.05 mm (0.0020 in.)
    Intake manifold side
    		0.10 mm (0.0039 in.)
    Exhaust manifold side
    		0.10 mm (0.0039 in.)

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



2. INSPECT CYLINDER HEAD FOR CRACKS


    A198668

  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 VALVE SEATS


    A146287E03

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

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

  1. Check the valve face and valve seat according to the following procedure:

    1. If Prussian blue appears 360° around the valve face, the valve face is concentric. If not, replace the valve.
      Text in Illustration 
      *a
      		Width

    2. If Prussian blue appears 360° around the valve seat, the guide and valve face are concentric. If not, resurface the valve seat.

    3. Check that the valve seat contact is in the middle of the valve face with the valve seat width between 1.0 and 1.4 mm (0.0394 to 0.0551 in.).



4. INSPECT INTAKE VALVE


    A126904

  1. Using a gasket scraper and wire brush, scrape off any carbon on the valve head.



    A121380E03

  1. Using a vernier caliper, measure the overall length of the valve.
    Text in Illustration 
    *a
    		Overall Length

    Standard overall length:
    103.35 mm (4.0689 in.)

    Minimum margin thickness:
    102.85 mm (4.0492 in.)

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



    A121378

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

    Valve stem diameter:
    5.470 to 5.485 mm (0.21535 to 0.21594 in.)

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



    A014597E03

  1. Using a vernier caliper, measure the valve head margin thickness.
    Text in Illustration 
    *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 valve.



5. INSPECT EXHAUST VALVE


    A126904

  1. Using a gasket scraper and wire brush, scrape off any carbon on the valve head.



    A121383E03

  1. Using a vernier caliper, measure the overall length of the valve.
    Text in Illustration 
    *a
    		Overall Length

    Standard overall length:
    104.5 mm (4.114 in.)

    Minimum overall length:
    104.0 mm (4.0945 in.)

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



    A121381

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

    Valve stem diameter:
    5.465 to 5.480 mm (0.21516 to 0.21575 in.)

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



    A121382E03

  1. Using a vernier caliper, measure the valve head margin thickness.
    Text in Illustration 
    *a
    		Margin Thickness

    Standard margin thickness:
    1.15 mm (0.0453 in.)

    Minimum margin thickness:
    0.65 mm (0.0255 in.)

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



6. INSPECT VALVE GUIDE BUSH OIL CLEARANCE


    A198672

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

    Bushing inside diameter:
    5.51 to 5.53 mm (0.2169 to 0.2177 in.)

  1. 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
    		0.080 mm (0.00315 in.)
    Exhaust
    		0.085 mm (0.00335 in.)

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



7. INSPECT COMPRESSION SPRING


    EM00801

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

    Free length:
    51.19 mm (2.0154 in.)

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



    EM00988E09

  1. Using a steel square, measure the deviation of the valve spring.
    Text in Illustration 
    *a
    		Deviation

    Maximum deviation:
    1.8 mm (0.0709 in.)

    If the deviation is greater than the maximum, replace the valve spring.