About This Quiz
So you think you're a real gearhead? We've got a quiz to test your knowledge in a specific area ... the components of the engine!
But first, a little background. After millennia of using strong animals like horses and oxen to pull vehicles, or to power other forms of machinery, humans began dreaming of machines that would power themselves. They didn't, though, agree on what kind of fuel might power the earliest engines. One early effort used hydrogen (an idea some have come back to as fossil fuels lose their appeal). The first winner, however, was steam — with coal being the raw fuel that boiled the water. Later, it was largely a German, Karl Benz (his last name might be familiar) who was responsible for the ultimate choice of petroleum fuel (that's gasoline, to us everyday people) to power what became known as the internal combustion engine.
"Internal combustion" means that the vehicle or machine has no external power source — it's essentially a little power plant all its own. This is especially true of cars, where the engine not only burns gas to turn the wheels but provides electricity for the car's other systems — its interior lights, the radio, the climate control and more — that makes driving a pleasure and not just a convenience.
Are you ready to test your knowledge of what's under the hood? Good luck!
Alternators produce alternating current, which is converted to direct current by auxiliary parts. Alternators became increasingly important as cars gained a lot of electrical creature comforts, like heated seats and subwoofers.
Belts of various kinds have been essential to the workings of machines since the first days of engineering. The fan belt runs the cooling fan in the engine, hence the name.
The engine block is where the magic happens! Or, at least, where the essentials of combustion occur.
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"Turbocharging" takes its name from the use of exhaust gas to drive a turbine that forces extra compressed air (and fuel) into the cylinder for more power. A supercharger works similarly but is powered by the car's electrical system to avoid turbo lag.
Sorry, dipstick, but while you're part of the lubrication system, you are somewhat less than essential. It's the oil pump that gets the engine's oil where it needs to be, which keeps everything running smoothly.
The answer. of course, is "dipstick." There's a cruder version of this insult, but we can't say it here.
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The piston travels up and down in the cylinder, moved from the force of the fuel/air combustion. Fun fact: A skull and crossed pistons is the symbol of the Outlaws Motorcycle Club. They are the traditional rivals of the Hell's Angels.
Of course, many engine parts are hot to the touch when the ignition's first shut off. But trying to take the cap off the radiator in an overheat situation is a way to give yourself a nasty steam burn.
Catalytic converters work by using a chemical reaction to convert harmful emissions (carbon monoxide, nitrogen oxides and hydrocarbons) to less harmful ones. It isn't just vehicles that use catalytic converters, either; they are found in fuel-burning stoves and heaters, as well.
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An intake manifold supplies the fuel/air mixture to the combustion cylinders. An exhaust manifold takes the exhaust gases from the combustion process and shunts them all into one pipe.
A cylinder, in geometry, is a three-dimensional figure defined by two circles, one at each end — or you could just visualize a can. In the engine, it's where the fuel-air mixture is compressed and ignited, moving the pistons to generate motion.
In general, a gasket is a seal. A head gasket keeps the cylinder from losing compression, which would make the engine lose power.
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A chief engineering problem in making the earliest cars, trucks, etc, was getting power, or motion, to "change direction," so to speak, from the up-and-down motion of the pistons to the rotational motion needed to move the wheels. The crankshaft is an important part of that, transferring the energy generated by the combustion process — or its initial motion — to the powertrain.
The name is apt — it distributes electricity. The reason the distributor has to do this in a particular order is that the cylinders must fire in a certain side-to-side order for balance. Otherwise, the engine would rock violently enough to shake the car.
Of course, it's the oil filter. You don't want your new oil contaminated with the old oil's dirt. Keeping the engine oil free of gunk is critical to keeping the engine running well for years.
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The camshaft rotates pear-shaped plates, whose intermittent pressure causes the valves to open and close. This part of the engine is the source of all those commercials gloating over an engine's "double overhead cam."
This is a change from older flathead engines. In those, the valves were in the cylinder block.
The fan, one of the simplest human inventions for keeping cool, is still essential to the functioning of modern cars.
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Unsurprisingly, the rocker arm is named for its characteristic motion, which takes the circular motion of the cam lobe into the linear movement needed to open the poppet valve. We would have liked for it to have been invented by Alice Cooper on his day off, but sadly, that's not the case.
Your car battery doesn't actually have much more voltage than the one you'd put in a smoke alarm. The ignition coil, or spark coil, increases the voltage until it's capable of firing the spark plugs, which is essential to the combustion process.
A "poppet valve" was sometimes called a "puppet valve." Both terms come from the idea of the valve being controlled from above and making an up-and-down motion, like a puppet. It's also sometimes called a "mushroom valve" because of its shape.
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In the movie, "Road to Perdition," a boy is asked what the clutch does, and says, "it clutches." Well, not exactly. The clutch is several discs that connect and disconnect shafts, meaning it is the key connection between the engine and drive train. When you take your foot off the clutch pedal, you are actually "letting out" the clutch, not engaging it. Many people get this backward.
The starter motor is what comes to life when you crank the ignition. It powers the first two strokes of the engine's four-stroke cycle, after which the process becomes self-perpetuating.
A car's battery looks sizable and impressive, but it often has only 12.6 volts and is used primarily to provide the energy to start the engine. The rest of the electricity that makes the engine work and provides all those enjoyable extras — like the radio — are generated from the engine and the alternator.
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A propelling nozzle is a part of a gas turbine which helps to maximize the velocity of the propelling gases exiting the engine. These are used in jet engines, which have turbofan engines.
Magnetos aren't entirely gone; some airplanes still use them because they can help provide redundancy and enhanced combustion. (It's also possible that engineers liked the cool, atomic-age name so much they couldn't let them go completely obsolete).
The wrist pin doesn't just connect the piston and connecting rod. It also allows greater flexibility, letting the rod adapt to the motion of the piston without breaking.
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The solenoid is an electromagnet that, when you turn the key, closes a pair of contacts that allows current to flow through the starter motor and gets the ignition process started. You might remember the solenoid from its use in the 2005 "War of the Worlds" remake. Tom Cruise's mechanically inclined character suggests that replacing the solenoid in a car will correct the ignition failure caused by an electromagnetic pulse.
This is a protective housing for the crankshaft and its connecting rods. It's also oddly fun to say aloud.
The thermostat is located between the engine and the radiator and, once the engine gets hot enough, opens to allow coolant to flow and maintain a proper temperature. It's a simple but essential piece of technology for your vehicle.
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The full definition of a flywheel is a bit complex, but suffice to say it stores and smooths out the flow of the intermittent energy produced by the constantly moving pistons.
A multi-accessory belt, as the name implies, replaced a system that used several belts to run various engine parts like the water pump and the alternator. It's more efficient than multiple belt systems, but the downside is that, if this belt breaks, a lot goes wrong all at once.
Many veteran mechanics have a story about breaking off a spark plug in the block. The best ones will also tell you the first step in dealing with it: Go have a cup of coffee or take a walk until you're not upset any more and can approach the problem with a cool head and a lot of penetrating oil.
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Strictly speaking, only overhead cam engines contain a part that could be called a tappet. In fact, a tappet is a fairly general term, meaning "an outcropping part that causes linear motion," However, it's associated enough with engines that car experts Tom and Ray Magliozzi called themselves, "Click and Clack, the Tappet Brothers" on their "Car Talk" radio program.
The advent of distributor-less ignition might have been progress in terms of engine design. However, it ruined a good theft-protection and drunk-driving prevention strategy — stealing the distributor cap. Since it was easy to remove, and the car would go nowhere without it, it was a quick way to disable the vehicle.