What is the most frequently used firing order in four-cylinder inline internal combustion engines__________________?
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Answer: B. 1-3-2-4
Explanation
Four-cylinder inline internal combustion engines require a carefully selected firing order to maintain smooth rotational balance. The sequence 1-3-2-4 distributes power strokes evenly across the 720-degree combustion cycle of a four-stroke engine. This specific firing order minimizes primary and secondary unbalanced engine vibrations and reduces crankshaft torsional stress. Four-stroke engines fire each cylinder once every two complete revolutions of the crankshaft, equaling 720 degrees of rotation. Spacing power intervals evenly at 180-degree increments prevents overlapping power pulses and rough engine operation. Inline four-cylinder engine design inherently balances primary reciprocating forces but requires careful firing sequence for smooth torque delivery.
Option A of 1-2-3-4 creates uneven power intervals and severe mechanical imbalances that destroy engine main bearings quickly. Options C and D represent alternative or non-standard configurations that are rarely used in commercial inline four-cylinder engines. Option E is incomplete and invalid as a functional engine firing order sequence.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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