| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.01 |
| Score | 0% | 60% |
Too much fuel results in a __________ air-fuel mixture that burns quicker and cooler.
lean |
|
rich |
|
light |
|
heavy |
The stoichiometric ratio defines the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air. For gasoline fuel, the stoichiometric ratio is about 14.7:1 or for every one gram of fuel, 14.7 grams of air are required. Too much air results in a lean air-fuel mixture that burns more slowly and hotter while too much fuel results in a rich mixture that burns quicker and cooler.
__________ results from oil buildup in the combustion chamber.
detonation |
|
engine knock |
|
combustion |
|
preignition |
Preignition results from the buildup of fuel deposits and/or oil in the combustion chamber. These deposits increase chamber pressure and reduce heat tranfer to the coolant. The trapped heat then raises the temperature of the air-fuel mix to the point that it combusts before ignition.
The stoichiometric ratio is approximately:
1:1 |
|
14.7 |
|
14.7:1 |
|
1:14.7 |
The stoichiometric ratio defines the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air. For gasoline fuel, the stoichiometric ratio is about 14.7:1 or for every one gram of fuel, 14.7 grams of air are required. Too much air results in a lean air-fuel mixture that burns more slowly and hotter while too much fuel results in a rich mixture that burns quicker and cooler.
What type of energy does an automotive battery produce?
chemical energy |
|
alternating current |
|
rotational energy |
|
direct current |
An automotive battery produces direct current for use by automotive systems.
Engine oil viscosity is rated using the format XW-XX with the number preceding the W indicating viscosity at __________ ℉ and the XX indicating viscosity at __________ ℃.
0, 100 |
|
100, 100 |
|
0, 0 |
|
100, 0 |
The primary component of the lubrication system is engine oil. Engines require oil blends with different thickness (viscosity) and additives depending on their operating conditions. Viscosity is rated using the format XW-XX with the number preceding the W (winter) rating the oil’s viscosity at 0 ℉ (-17.8 ℃) and the XX indicating viscosity at 100 ℃.