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Valve Spring: Testing and Inspection

1. Using a suitable tester, check the valve spring free length and tension. If they exceed the service limit, replace the spring.
Standard Value:
Free height:
46.07 mm (1.8137 inch)
Height at load:
25.5 kg (56.23 lbs.) at 37 mm (1.4578 inch)
57.3 kg (126.35 lbs.) at 28 mm (1.1032 inch)






2. Using a square, test the squareness of each spring. If the spring is excessively out of square, replace it.
Standard Value:
3° or less.