During exhaust valve inspection go-no-go gauge checks are used to assess wear on which component?

During exhaust valve inspection go-no-go gauge checks are used to assess wear on which component?

• A. Valve guides for wear
• B. Valve seats for wear
• C. Valve stems for straightness
• D. Valve springs for tension

Answer: (A)

Go-no-go gauges are used to quickly determine if a dimension has worn beyond its specified limit. In exhaust valve inspection, they’re applied to the valve guide bore because wear in the guides changes the internal diameter where the valve stem travels. If the guide wears, the bore enlarges and the valve stem can no longer fit/float properly, leading to leakage and oil consumption. The go gauge should pass if the bore is within tolerance, while the no-go gauge should not fit; if the no-go fits, the guide is worn beyond limits and needs attention. Other components are checked with different tools: the valve stem diameter and straightness with micrometers and gauges, the valve seat with seat gauges, and the spring tension with a spring tester. The go-no-go method specifically targets guide wear because the guide’s internal wear directly affects how the stem interacts with the guide.

Go-no-go gauges are used to quickly determine if a dimension has worn beyond its specified limit. In exhaust valve inspection, they’re applied to the valve guide bore because wear in the guides changes the internal diameter where the valve stem travels. If the guide wears, the bore enlarges and the valve stem can no longer fit/float properly, leading to leakage and oil consumption. The go gauge should pass if the bore is within tolerance, while the no-go gauge should not fit; if the no-go fits, the guide is worn beyond limits and needs attention.

Other components are checked with different tools: the valve stem diameter and straightness with micrometers and gauges, the valve seat with seat gauges, and the spring tension with a spring tester. The go-no-go method specifically targets guide wear because the guide’s internal wear directly affects how the stem interacts with the guide.