🔍 Key Concepts

• Relationship between exhaust smoke color and engine condition (blue vs black vs white) • How lubricating oil entering the combustion chamber affects exhaust appearance • Function of oil control rings and what happens when they don’t drain oil properly

💭 Think About

• Think about what has to happen inside a cylinder for exhaust to turn blue rather than black or white — what substance is getting burned? • Which choice describes a condition that would allow excess lube oil to be present in the combustion space? • Consider which options describe fuel-related issues versus lubricating-oil–related issues.

✅ Before You Answer

• Identify which option is specifically related to lubricating oil control, not just fuel or load. • Eliminate any option that would more likely cause black smoke (excess fuel/incomplete combustion) or white smoke (unburned fuel/cool cylinder/steam). • Check which choice directly involves the oil control rings’ ability to return oil from the cylinder walls back to the crankcase.