Question 148Motor Plants - 1st Asst/Chief

70% to pass

While examining a used fuel injection nozzle(s), one finds worn and enlarged orifices. What does this indicate about that cylinder's performance prior to nozzle replacement(s)?

AVolume of atomization is increased, penetration is reduced, vaporization is increased, efficiency is not effected.
BVolume of fuel injected is increased, reduced injection pressure, decreased ignition delay.
CReduced combustion efficiency, increased ignition delay, reduced atomization, prolonged penetration.
DPenetration is increased, air/fuel mixture is increased, cylinder efficiency is not substantially effected.
AI Explanation

The correct answer is C) Reduced combustion efficiency, increased ignition delay, reduced atomization, prolonged penetration. Worn and enlarged fuel injection nozzle orifices indicate that the fuel injection process has been compromised. This leads to reduced atomization of the fuel, causing larger fuel droplets and prolonged penetration into the cylinder. As a result, the air-fuel mixture quality is reduced, leading to decreased combustion efficiency and increased ignition delay. The other answer choices do not accurately describe the effects of worn fuel injection nozzles on cylinder performance.

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