Valve Spring: Testing and Inspection

1. Using a ruler, measure the height of the valve spring at four locations. If the spring is bent, replace it. Intake and Exhaust Valve Squareness:
^ Standard: 2.0 mm (0.080 inch)max.
^ Service Limit: 2.5 mm (0.100 inch) max.





2. Using calipers, measure the free length of the valve spring. If the free length is not within specification, replace the valve spring. Free Length:
^ Standard: 43.7 mm (1.72 inch) min.





3. Using a spring tester SA9183NE (or equivalent), fully collapse the spring three times, then measure the tension of the intake and exhaust valve springs at the specified installed length. If the installed tension is not as specified, replace the valve spring.
Tension at 26.25 mm (1.033 inch):
^ Standard: 560-632 N (126-142 lbs.)
^ Service Limit: 534 N (120 lbs) min.
Tension at 35.25 mm (1.388 inch):
^ Standard: 245-294 N (55-66 lbs)
^ Service Limit: 231 N (52 lbs) min.