ASE A1 Engine RepairCylinder Head and Valve TrainHard
A technician is performing a cylinder head overhaul and notices that one of the valve springs has a small amount of corrosion and a slight bowing (not perfectly straight). The spring's free length and pressure test results are within specifications. What action should the technician take regarding this valve spring?
- AClean the corrosion and install the spring.
- BInstall the spring, as it meets specifications.
- CReplace the valve spring.
- DInstall the spring but mark it for future replacement.
Show answer & explanationAnswer & explanation
Correct answer: C. Replace the valve spring.
Even if the free length and pressure test are within specifications, any sign of corrosion or bowing indicates a compromised valve spring. Corrosion can lead to stress risers and premature fatigue, while bowing suggests a loss of structural integrity. A valve spring failure can lead to catastrophic engine damage, so it's always best to replace a suspect spring.
Why the other options are wrong
- A. Cleaning corrosion doesn't fix the underlying material degradation or bowing, which are signs of weakness.
- B. While meeting current specs, the visible damage indicates latent failure risk.
- D. Installing a known compromised part, even with a mark, is poor practice and risks engine damage soon after repair.
Valve Spring Integrity
The overall physical condition and structural soundness of a valve spring, including its straightness, absence of corrosion, and freedom from cracks or fatigue, which are critical for reliable engine operation.
- Corrosion or bowing indicates weakness, even if specs are met.
- Failure can lead to severe engine damage.
- Always replace suspicious springs during an overhaul.
Memory trick: Corrosion or bend, spring's end is nigh, replace it, don't try.