YAMAHA VALVE SPRING 68D-E2113-00

Function and technical context

The valve spring is a critical component of the valve train that regulates the precise opening and closing of the intake and exhaust valves on Yamaha outboard engines. It works under thousands of compression and extension cycles per minute, forced by the camshaft, and guarantees that each valve returns to its closed position after each actuation. Its correct operation is essential to maintain the exact timing of the combustion cycle, preserve the tightness of the combustion chamber and ensure the power, efficiency and controlled consumption of the engine. A deteriorated or weakened spring causes loss of power, excessive fuel consumption, irregular running and possible progressive damage to the cylinder head and adjacent components.

When to replace this part?

Valve springs experience progressive fatigue from continuous cyclic work and can lose tension, warp or break after hundreds of hours of operation. Typical symptoms include rough running, loss of acceleration, abnormal knocking in the cylinder head, difficulty starting, and abnormal engine vibrations. It is recommended to check the condition of the valve springs during each seasonal maintenance, especially in engines with more than 300-400 hours of operation, and replace them preventively if deformation, loss of load or breakage is detected. Changing the springs preventively avoids unforeseen navigation breakdowns and costly valve train repairs that can leave the boat immobilized.

Equivalent manufacturer part numbers