Grey smoke exhausting from a running diesel...

Question 1 / 270705eccefa2bacbc34ba4d47b83

Question 1 of 270705eccefa2bacbc34ba4d47b83

Grey smoke exhausting from a running diesel engine can be caused by __________.

Question 1 of 27070

Grey smoke exhausting from a running diesel engine can be caused by __________.

🔍 Key Concepts

• diesel engine combustion and exhaust colors (black, blue, white/grey) • effects of water or contamination in fuel on combustion • relationship between ignition timing and exhaust appearance

💭 Think About

• Think about what incomplete or poor combustion looks like in a diesel engine and how that appears at the exhaust. • Which of these conditions would cause fuel not to burn completely and create a hazy grey exhaust instead of a sharp black or bluish smoke? • Consider whether each option would more likely change temperature/pressure inside the cylinder or actually disrupt normal fuel burning.

✅ Before You Answer

• For each choice, ask: does this cause poor or incomplete combustion that could make a cool, misty-looking exhaust? • Recall typical color associations: black (soot/unburned fuel from overfueling), blue (burning lube oil), white/grey (unburned or partially burned fuel, often cooler). • Eliminate any options that would normally make combustion hotter and more complete, rather than cooler or interrupted.

Question 1 of 27070

Grey smoke exhausting from a running diesel engine can be caused by __________.

late ignition

water in the fuel

high compression temperature

starting valve stuck open