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Valve Spring: Testing and Inspection






1. Check the valve spring free length and tension. If they exceed the service limit, replace the spring.
Standard value:
Free height, 48.3 mm (1.902 inch).
Load, 300 N (66 Lb.) @ 40 mm (1.575 inch).
Wear Limit:
Free height, 47.3 mm (1.862 inch)
2. Using a square, test the squareness of each spring. If a spring is excessively out of square, replace it.
Standard value:
Out of square, less than 1.5°.
Wear Limit:
Out of square, 4°.