Valve and Valve Spring

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

   Valve guide inner diameter (Intake/Exhaust):  5.500 - 5.512 mm (0.21653 - 0.21700 in.)

   Courtesy of HYUNDAI MOTOR AMERICA

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

   Valve stem outer diameter 

   Intake: 5.460 - 5.475 mm (0.21496 - 0.21555 in.)

   Exhaust: 5.453 - 5.465 mm (0.21468 - 0.21515 in.)

   Courtesy of HYUNDAI MOTOR AMERICA

3. Calculate the gap between the valve guide and the valve stem by subtracting the difference between the measured value of the valve guide inner diameter and the stem outer diameter.

   Valve stem-to-guide clearance 

   Intake: 0.025 - 0.052 mm (0.0010 - 0.0020 in.)

   Exhaust: 0.035 ~ 0.059 mm (0.0014 - 0.0023 in.)

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

1. Check the angle of the valve face.
2. Check the contact surface of the valve for wear. If the valve is excessively worn, replace the valve.
3. Check the valve margin thickness.

   Valve head thickness (Margin) 

   [Standard]

   Intake: 0.8 mm (0.0314 in.)

   Exhaust: 0.8 mm (0.0314 in.)

   Courtesy of HYUNDAI MOTOR AMERICA

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

4. Check the valve length.

   Valve length 

   Intake: 108.378 mm (4.2668 in.)

   Exhaust: 119.878 mm (4.7196 in.)

   Intake: 108.228 mm (4.2609 in.)

   Exhaust: 119.728 mm (4.7137 in.)

Check the valve seat for evidence of overheating and valve face contact condition. Replace the cylinder head if the valve seat is worn.

Check the valve guide for wear. If the valve guide is worn, replace the cylinder head.

1. Using a steel square ruler, measure the out-of-square of the valve spring.
2. Using a vernier calipers, measure the free length of the valve spring.

   Free length:  Intake: 52.51 mm (2.0673 in.)

   Exhaust: 56.05 mm (2.2067 in.)

   Squareness: Less than 1.5°

   Courtesy of HYUNDAI MOTOR AMERICA