Connecting Rod, Flywheel & Crank Throw MCQs with Explanation

Correct Answer: C. Piston

• The small end of the connecting rod is connected to the piston by using a piston pin.
• The big end of the connecting rod is connected to the crankshaft by using a crank pin.
• The connecting rod converts the linear reciprocating motion of the piston into rotary motion of the crankshaft.
• So, the connecting rod acts as the important link between piston and crankshaft.

Correct Answer: B. Flywheel

• Flywheel is attached to the rear end of the crankshaft by means of bolts.
• The crankshaft transmits torque to the flywheel.
• The inertia of the flywheel tends to keep the crankshaft rotating at a constant speed.
• The flywheel stores energy during the power stroke.
• It supplies energy to the crankshaft during idle strokes: suction, compression and exhaust strokes.

Correct Answer: C. 120 degree

• In a four-stroke single-cylinder engine, one power stroke occurs for every 720° crankshaft rotation.
• For a six-cylinder engine, power strokes are equally distributed among six cylinders.
• Therefore, angle between successive power strokes = 720° ÷ 6 = 120°.
• Hence, six crank throws are placed at 120° out of phase with one another.