Answer :
Final answer:
A feeler gauge is used to measure piston ring side clearance, providing precise gap measurements essential for engine maintenance.
Explanation:
The correct tool for measuring piston ring side clearance is a feeler gauge. A feeler gauge is a tool that consists of a set of thin metal strips of precise thicknesses used to measure the clearance or gap between two parts. For engine assembly and maintenance, including the measurement of piston ring side clearance, it is critical to use a feeler gauge to ensure that there is the correct amount of space for the piston ring to expand when it gets hot during engine operation.
