Valve And Valve Spring

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

   Valve guide inner diameter (Intake/Exhaust): 

   5.505 - 5.517 mm (0.2167 - 0.2172 in.)

   Courtesy of HYUNDAI MOTOR AMERICA

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

   Valve stem outer diameter 

   Intake: 5.465 - 5.480 mm (0.2152 - 0.2157 in.)

   Exhaust: 5.458 - 5.470 mm (0.2149 - 0.2154 in.)

   Courtesy of HYUNDAI MOTOR AMERICA

3. Subtract the valve stem outer diameter measurement from the valve guide inner diameter measurement.

   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 specification, replace the valve or the cylinder head.

1. Check the valve is ground to the correct valve face angle.
2. Check that the surface of valve for wear.

   If the valve face is worn, replace the valve.

3. Check the valve head margin thickness.

   Valve head thickness (Margin) 

   Standard

   Intake: 0.70 mm (0.0276 in.)

   Exhaust: 0.91 mm (0.0358 in.)

Courtesy of HYUNDAI MOTOR AMERICA

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

1. Check the valve seat for evidence of overheating and improper contact with the valve face. If the valve seat is worn, replace the cylinder head.
2. Check the valve guide for wear. If the valve guide is worn, replace the cylinder head.

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

   Valve spring 

   Free height

   Intake: 52.55 mm (2.0689 in.)

   Exhaust: 50.00 mm (1.9685 in.)

   Out of square: Less than 1.5°