CYLINDER HEAD > INSPECTION

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1. INSPECT CYLINDER HEAD SUB-ASSEMBLY


  1. Inspect the flatness.



    1. Using a precision straightedge and feeler gauge, measure the warpage on the cylinder block side and the intake and exhaust manifold sides.

      Maximum Warpage:
      Surface
      		Specified Condition
      Cylinder block side
      		0.08 mm (0.0032 in.)
      Intake manifold side
      		0.20 mm (0.0079 in.)
      Exhaust manifold side
      		0.20 mm (0.0079 in.)

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


      A198436E01



    A198437

  1. Inspect for cracks.

    1. Using a dye penetrant, check the combustion chambers, intake ports, exhaust ports and contact surface of the cylinder block for cracks.
      If cracked, replace the cylinder head.



2. INSPECT VALVE SEAT


    A077457E01

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

  1. Gently push the valve seat with the valve installed onto the cylinder head.

    NOTICE:
    Do not rotate the valve.

  1. Remove the valve from the cylinder head.

    1. If blue appears 360° around the face, the valve is concentric. If not, replace the valve.

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

    3. Check that the seat contact is in the middle of the valve face with the following width.



3. INSPECT CAMSHAFT OIL CLEARANCE


    A068049

  1. Clean the camshaft and camshaft bearing cap.

  1. Set the camshaft to the cylinder head.

  1. Lay a strip of Plastigage across the camshaft journal.

    NOTICE:
    Do not turn the camshaft when measuring.

  1. Install the bearing cap.

  1. Remove the bearing cap.



    A068050

  1. Measure the Plastigage at its widest point.

    Standard oil clearance:
    0.037 to 0.073 mm (0.0015 to 0.0029 in.)

    Maximum oil clearance:
    0.10 mm (0.0039 in.)

    NOTICE:
    Completely remove the Plastigage.

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



4. INSPECT CAMSHAFT THRUST CLEARANCE

  1. Set the camshaft to the cylinder head, and then install the camshaft bearing cap.

  1. Install the camshaft timing sprocket onto the camshaft.



    A198438

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

    Standard thrust clearance:
    0.040 to 0.090 mm (0.0016 to 0.0035 in.)

    Maximum thrust clearance:
    0.25 mm (0.0098 in.)

    If the thrust clearance is greater than the maximum, replace the cylinder head sub-assembly or camshaft.



5. INSPECT INTAKE VALVE


    EM02534E01

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

    Standard overall length:
    99.69 to 100.29 mm (3.9248 to 3.9484 in.)

    Minimum overall length:
    99.19 mm (3.9051 in.)

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



    Z000052E05

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

    Valve stem diameter:
    5.970 to 5.985 mm (0.2350 to 0.2356 in.)



    A077462E01

  1. Using a vernier caliper, measure the thickness of the valve head margin.

    Standard margin thickness:
    1.2 mm (0.047 in.)

    Minimum margin thickness:
    0.6 mm (0.024 in.)

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



6. INSPECT EXHAUST VALVE


    EM02534E01

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

    Standard overall length:
    99.39 to 99.99 mm (3.9130 to 3.9366 in.)

    Minimum overall length:
    98.89 mm (3.8933 in.)

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



    Z000052E05

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

    Valve stem diameter:
    5.965 to 5.980 mm (0.2348 to 0.2354 in.)



    A077462E01

  1. Using a vernier caliper, measure the thickness of the valve head margin.

    Standard margin thickness:
    1.5 mm (0.059 in.)

    Minimum margin thickness:
    0.7 mm (0.028 in.)

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



7. INSPECT INNER COMPRESSION SPRING


    EM00801

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

    Free length:
    42.17 mm (1.6602 in.)

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



    A077461E01

  1. Using steel squares, measure the deviation of the inner compression spring.

    Maximum deviation:
    1.5 mm (0.059 in.)

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



8. INSPECT VALVE GUIDE BUSH OIL CLEARANCE


    G035864

  1. Using a caliper gauge, measure the internal diameter of the valve guide bushing.

    Bushing inside diameter:
    6.010 to 6.030 mm (0.2366 to 0.2374 in.)

  1. Subtract the valve stem diameter measurement from the internal diameter measurement of the valve guide bushing.

    Standard Oil Clearance:
    Guide Bush
    		Specified Condition
    Intake
    		0.025 to 0.060 mm (0.0010 to 0.0024 in.)
    Exhaust
    		0.003 to 0.065 mm (0.0001 to 0.0026 in.)

    Maximum Oil Clearance:
    Guide Bush
    		Specified Condition
    Intake
    		0.08 mm (0.0031 in.)
    Exhaust
    		0.10 mm (0.0039 in.)

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