PROCEDURE
INSPECT CYLINDER HEAD SUB-ASSEMBLY
Using a precision straightedge and feeler gauge, measure the warpage of the surface where the cylinder head sub-assembly contacts the cylinder block sub-assembly, and the surfaces where the cylinder head sub-assembly contacts each manifold.
*a | Cylinder Block Side | *b | Exhaust Manifold Side |
*c | Intake Manifold Side | - | - |
Maximum Warpage | ||||||||
---|---|---|---|---|---|---|---|---|
|
If the warpage is more than the maximum, replace the cylinder head sub-assembly.
Using a dye penetrant, check the intake ports, exhaust ports and cylinder surface for cracks.
If there are cracks, replace the cylinder head sub-assembly.
INSPECT INNER COMPRESSION SPRING
Using a vernier caliper, measure the free length of the inner compression spring.
Standard Free Length |
---|
45.9 mm (1.81 in.) |
If the free length is not as specified, replace the inner compression spring.
Using a steel square, measure the deviation of the inner compression spring.
*a | Deviation |
Maximum Deviation |
---|
1.5 mm (0.0591 in.) |
Maximum Angle (Reference) |
---|
2° |
If the deviation is more than the maximum, replace the inner compression spring.
INSPECT INTAKE VALVE
Using a gasket scraper, chip off any carbon from the intake valve head.
Be careful not to damage the intake valve face.
Using a wire brush, thoroughly clean the intake valve.
Using a vernier caliper, measure the overall length of the intake valve.
*a | Overall Length |
Standard Overall Length |
---|
104.4 mm (4.11 in.) |
Minimum Overall Length |
---|
104.1 mm (4.10 in.) |
If the length is less than the minimum, replace the intake valve.
Using a micrometer, measure the diameter of the intake valve stem.
Standard Valve Stem Diameter |
---|
5.970 to 5.985 mm (0.23504 to 0.23563 in.) |
If the diameter is not as specified, replace the intake valve.
Using a vernier caliper, measure the intake valve head margin thickness.
*a | Margin Thickness |
Standard Margin Thickness |
---|
1.40 to 1.60 mm (0.0551 to 0.0630 in.) |
Minimum Margin Thickness |
---|
0.50 mm (0.0197 in.) |
If the margin thickness is less than the minimum, replace the intake valve.
INSPECT EXHAUST VALVE
Using a gasket scraper, chip off any carbon from the exhaust valve head.
Be careful not to damage the exhaust valve face.
Using a wire brush, thoroughly clean the exhaust valve.
Using a vernier caliper, measure the overall length of the exhaust valve.
*a | Overall Length |
Standard Overall Length |
---|
104.1 mm (4.10 in.) |
Minimum Overall Length |
---|
103.8 mm (4.09 in.) |
If the length is less than the minimum, replace the exhaust valve.
Using a micrometer, measure the diameter of the exhaust valve stem.
Standard Valve Stem Diameter |
---|
5.960 to 5.975 mm (0.23464 to 0.23524 in.) |
If the diameter is not as specified, replace the exhaust valve
Using a vernier caliper, measure the exhaust valve head margin thickness.
*a | Margin Thickness |
Standard Margin Thickness |
---|
1.36 to 1.56 mm (0.0535 to 0.0614 in.) |
Minimum Margin Thickness |
---|
0.50 mm (0.0197 in.) |
If the margin thickness is less than the minimum, replace the exhaust valve.
INSPECT VALVE GUIDE BUSH
Using a caliper gauge, measure the inside diameter of the valve guide bush.
Standard Bush Inside Diameter |
---|
6.010 to 6.030 mm (0.23661 to 0.23740 in.) |
If the bush inside diameter is not as specified, check the oil clearance.
Subtract the valve stem diameter measurement from the valve guide bush inside diameter measurement.
Standard Oil Clearance | ||||||
---|---|---|---|---|---|---|
|
Maximum Oil Clearance | ||||||
---|---|---|---|---|---|---|
|
If the oil clearance is more than the maximum, replace the valve and valve guide bush.
INSPECT INTAKE VALVE SEAT
Apply a light coat of Prussian blue to the intake valve face.
Lightly press the intake valve face against the intake valve seat.
Do not rotate the valve while pressing it.
Check the intake valve face and intake valve seat by using the following procedure.
Check that Prussian blue appears around the entire intake valve face and that the intake valve face is concentric. If not, replace the intake valve.
Check that Prussian blue appears around the entire intake valve seat and that the guide and intake valve face are concentric. If not, resurface the intake valve seat.
Check that the intake valve seat contacts in the middle of the intake valve face with a contact surface width between 1.0 and 1.4 mm (0.0394 and 0.0551 in.).
*a | Width |
INSPECT EXHAUST VALVE SEAT
Apply a light coat of Prussian blue to the exhaust valve face.
Lightly press the exhaust valve face against the exhaust valve seat.
Do not rotate the valve while pressing it.
Check the exhaust valve face and exhaust valve seat by using the following procedure.
Check that Prussian blue appears around the entire exhaust valve face and that the exhaust valve face is concentric. If not, replace the exhaust valve.
Check that Prussian blue appears around the entire exhaust valve seat and that the guide and exhaust valve face are concentric. If not, resurface the exhaust valve seat.
Check that the exhaust valve seat contacts in the middle of the exhaust valve face with a contact surface width between 1.0 and 1.4 mm (0.0394 and 0.0551 in.).
*a | Width |
INSPECT CAMSHAFT OIL CLEARANCE
Click hereНажмите здесь