Valve Springs

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Each valve is closed by two or three helical springs. If a single spring were used, it would vibrate or surge at certain speeds.To eliminate this difficulty, two or more springs (one inside
the other) are installed on each valve. Each spring vibrates at a different engine speed and rapid damping out of all spring-surge vibrations during engine operation results. Two
or more springs also reduce danger of weakness and possible failure by breakage due to heat and metal fatigue. The springs are held in place by split locks installed in the recess of the valve spring upper retainer or washer, and engage a groove machined into the valve stem. The functions of the valve springs are to close the valve and to hold the valve securely on the valve seat.

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