Subtopic: Selection, operation, maintenance and repair of I.C. engines
Question Statement:
During engine maintenance and overhaul, cylinder bore 'ovality' (out-of-roundness) is evaluated by measuring bore diameters with a dial bore gauge:
Options:
(A) Across the major thrust axis (perpendicular to crankshaft) and along the longitudinal axis (parallel to crankshaft) at the same depth
(B) At the very top of the liner and the very bottom only
(C) Before and after washing the cylinder block with solvent
(D) With the piston rings installed inside the bore
Answer Key:
A
Step-by-Step Solution & Explanation
Cylinder ovality is the difference between transverse (thrust side) and longitudinal (parallel to crankshaft) bore diameters at identical depths, caused primarily by side-thrust forces of the piston during expansion and compression strokes.