Which item is not a measurement used for crankshaft journals: Diameter, Out-of-round, Taper, Color?

Which item is not a measurement used for crankshaft journals: Diameter, Out-of-round, Taper, Color?

• A. Diameter
• B. Out-of-round
• C. Color
• D. Taper

Answer: (C)

Crankshaft journals are evaluated by geometry that affects how the bearing surfaces ride and stay properly lubricated. The diameter is the basic size of the journal cross-section and must stay within tolerance so the bearing fits correctly and oil clearance is correct. Out-of-roundness checks how much the journal deviates from a perfect circle around its circumference; if the journal is oval, bearing clearance varies around the journal, leading to uneven wear. Taper looks at changes in diameter along the length of the journal; even a small taper can tilt the crankshaft relative to the bearings and disturb lubrication. Color isn’t a measured dimension or geometric property; while discoloration can hint at overheating or contamination, it isn’t used to quantify journal size or roundness. So the item that isn’t a measurement for crankshaft journals is color.

Crankshaft journals are evaluated by geometry that affects how the bearing surfaces ride and stay properly lubricated. The diameter is the basic size of the journal cross-section and must stay within tolerance so the bearing fits correctly and oil clearance is correct. Out-of-roundness checks how much the journal deviates from a perfect circle around its circumference; if the journal is oval, bearing clearance varies around the journal, leading to uneven wear. Taper looks at changes in diameter along the length of the journal; even a small taper can tilt the crankshaft relative to the bearings and disturb lubrication.

Color isn’t a measured dimension or geometric property; while discoloration can hint at overheating or contamination, it isn’t used to quantify journal size or roundness. So the item that isn’t a measurement for crankshaft journals is color.