Final answer:
In an engine with all lifters cupped, it is necessary to inspect both the cam and lifters for wear. Excessive wear on the lifters often indicates similar wear on the cam, suggesting that both should be replaced to maintain engine performance. Physical examination of the cam is essential to confirm its condition.
Step-by-step explanation:
The question is concerning a scenario where all lifters in an engine are found to be cupped or concave. This condition suggests wear patterns that need to be addressed to ensure the proper functioning of the engine. When it comes to diagnosing this kind of issue with lifters and determining if the cam should be replaced (as suggested by Tech A) or just the lifters (as suggested by Tech B), it's important to inspect both components thoroughly.
The cam and lifters work in tandem and excessive wear on the lifters can indicate similar wear on the cam lobes. Since the lifters are cupped, it is likely that the cam has sustained damage as well and may require replacement to avoid future engine problems. However, it is essential to physically examine the cam to confirm its condition before deciding on replacement.
To avoid recurrences of similar issues, it is advisable in many cases to replace both the cam and lifters as they are part of a system that relies on precision interactions. By doing so, you ensure that all components mesh correctly and wear evenly over time, maintaining engine performance and longevity.