What is required if a piston diameter is smaller than the specified service limits?

When a piston diameter is smaller than the specified service limits, it indicates that the piston has worn down beyond acceptable tolerances. This can lead to several issues, such as decreased engine performance, poor sealing, and excessive oil consumption. The proper course of action in such a scenario is to replace the piston.

Using a piston that does not meet the specified diameter can result in inadequate performance and potential engine damage since the piston is crucial for maintaining proper compression within the combustion chamber. Even if the clearance is deemed acceptable or if the piston can be resized, this may not address the fundamental issue of the piston being below the essential diameter requirement. Therefore, replacing the piston ensures that the engine operates efficiently and reliably within its design specifications.