Diesel Lubrication Systems

To minimize engine wear and the creation of heat, lubrication systems reduce __________ between moving engine parts.

• A. Friction

• B. Lubricity

• C. Cushioning

• D. Sealing

Technician A says that engine oils need to be compatible with the latest exhaust aftertreatment systems and biofuels. Technician B says aftertreatment systems do not play a role in the type of oil used in an engine. Who is correct?

• A. Technician A

• B. Technician B

• C. Both Technician A and Technician B

• D. Neither Technician A nor Technician B

Which of the following statements about lubrication systems is correct?

• Lubrication systems assist sealing of the combustion chamber by forming a film between the piston rings and the cylinder wall.

• Lubrication systems absorb shock loads between bearings and gears, thus cushioning and protecting engine parts while minimizing engine noise production.

• Both A and B

• Neither A nor B

Technician A says that at a microscopic level, highly polished metal surfaces are fairly smooth. Technician B says oil works by forming a separating film between parts to minimize direct contact between moving parts. Who is correct?

• Technician A

• Technician B

• Both Technician A and Technician B

• Neither Technician A nor Technician B

When discussing lubrication systems, Technician A says that the lubrication system lubricates moving parts, but cannot remove heat from the engine. Technician B says part of the lubrication system's job is to minimize corrosion of internal engine parts. Who is correct?

• Technician A

• Technician B

• Both Technician A and Technician B

• Neither Technician A nor Technician B

Which of the following statements about the benefits of synthetic oil is NOT correct?

• Users of synthetic oil have claimed increases in their fuel mileage ranging from 3% to 8%.

• There are longer intervals between oil changes due to higher resistance to oxidation.

• There is greater resistance to chemical breakdown, oxidation, coking, and deposit formation.

• There is reduced friction and engine wear because of a lower coefficient of friction.

Technician A says multi-grade oils are formulated with a feature to control viscosity change. Technician B says this change is measured by the viscosity index (VI), which refers to the change in oil viscosity with temperature. Who is correct?

• Technician A

• Technician B

• Both Technician A and Technician B

• Neither Technician A nor Technician B

Motor oils are typically made up of what percentage of chemical additives?

• 10-15%

• 15-25%

• 20-30%

• 25-45%

Which of the following statements about common oil additives is correct?

• Detergents and dispersants keep internal engine components clean and prevent thickening and sludging of oil.

• Emulsifiers prevent water from combining with engine oil.

• Corrosion and rust inhibitors protect engine parts against the effects of condensation.

• All of these are correct.

Engine oil with the assigned S-series designate tells us it is __________.

• Slippery

• Used in spark-ignited engines

• Used in single-cylinder engines

• Used in sequential-fired engines