Question 33Motor Plants - 1st Asst/Chief70% to pass
After testing your medium-speed engine's exhaust valve springs you find one with a spring constant that is lower than specified by design and a length that is reduced in length from that specified by design. What is the recommended course of action?
AI Explanation
The correct answer is D) Replace the spring and check the valves, cam, and follower for any damage caused by the spring bounce.
When an exhaust valve spring has a lower spring constant and reduced length compared to the design specifications, it indicates the spring has deteriorated and is no longer functioning as intended. Trying to anneal or stretch the spring to restore its properties is not recommended, as it may not reliably return the spring to its original specifications. The best course of action is to replace the spring entirely to ensure proper valve operation. Additionally, the reduced spring performance may have caused the valve to bounce excessively, potentially leading to damage to the valve, cam, or follower components. Inspecting these related components is crucial to identify and address any issues before the engine is returned to service.
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