Chapter 39 Combustion Efficiency ASE Quiz

Crude oil is used to make each of these EXCEPT:

• LPG.

• gasoline.

• hydrocarbons.

• hydrogen.

Crude oil is a mixture of:

• liquids.

• semisolids.

• hydrocarbons.

• All of the above.

Which of these is a commonly used antiknock additive?

• Naphthas.

• Oxygenates.

• Petrochemicals.

• None of the above.

Which of the following is the measurement of a fuel's ability to resist knock?

• Octane rating.

• Cetane rating.

• Cloud point.

• All of the above.

Normal combustion takes about:

• .01 seconds

• .003 seconds.

• .0003 seconds

• .00002 seconds

A chemically correct air-fuel ratio is called a:

• rich air-fuel mixture.

• lean air-fuel mixture.

• combustible fuel mixture.

• stoichiometric fuel mixture.

Each of these is a form or result of abnormal combustion EXCEPT:

• detonation.

• ignition lag.

• engine knock.

• after-running.

A diesel fuel substance that can separate from other fuel parts and clog fuel filters is:

• lead.

• water.

• carbon.

• parrafin.

Automakers recommend a cetane rating of about:

• 45

• 50

• 55

• 60

When looking at cetane ratings, Technician A says that the higher a cetane number is, the easier an engine starts and runs in cold weather. Technician B says that the higher a cetane number is, the easier a fuel ignites from heat and pressure. Who is right?

• Technician A only

• Technician B only

• Both Technician A and B

• Neither Technician A nor B