Which instrument is commonly used to check bearing clearance mentioned in the Plastigauge context?

• A. Plastigauge
• B. Feeler gauge
• C. Dial indicator
• D. Micrometer

Answer: (A)

Plastigauge is the instrument used in this context. It’s a soft plastic strip placed on the bearing surface before the cap is installed. When the cap is torqued to spec, the Plastigauge compresses and deforms to match the actual clearance between the bearing and the journal. After disassembly, you measure the width of the deformed Plastigauge against a calibrated scale to read the clearance directly, usually in thousandths of an inch or millimeters. This method provides a direct, practical measurement of bearing clearance and is the standard technique associated with Plastigauge. Feeler gauges, dial indicators, and micrometers can measure gaps or dimensions, but they don’t provide the same direct clearance reading in this bearing context.