| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.13 |
| Score | 0% | 63% |
The piston moves downward in the cylinder creating a vacuum that pulls an air-fuel mix into the combustion chamber. This describes which engine stroke?
intake |
|
compression |
|
power |
|
exhaust |
The four-stroke piston cycle of internal combustion engines starts with the piston at top of the cylinder head (top dead center or TDC) during the intake stroke. The piston moves downward in the cylinder creating a vacuum that pulls an air-fuel mix into the combustion chamber through the now open intake valve.
Which of the following is a relay that connects the battery to the starter motor when the ignition key is turned?
alternator |
|
solenoid |
|
ignition coil |
|
actuator |
The cylindrical solenoid is a relay that safely connects the high amperage battery to the starter motor when the ignition key is turned. This current then allows the engine to turn at a high enough speed to start.
Coolant is circulated through the engine by the:
water pump |
|
camshaft |
|
water jacket |
|
radiator |
The water pump is driven by a belt connected to the crankshaft and ensures that coolant moves through the engine and radiator.
Which of the following is the correct order for the engine stroke cycle?
power, intake, compression, exhaust |
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intake, compression, power, exhaust |
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intake, power, compression, exhaust |
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compression, intake, power, exhaust |
The stroke cycle order is intake stroke, compression stroke, power stroke, exhaust stroke.
Too much air results in a __________ air-fuel mixture that burns more slowly and hotter.
rich |
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lean |
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light |
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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.