Auto & Shop Information · Practice test 5

25 questions · 11 minutes

Answer every question, then tap Check results to see your score and the method behind each answer.

Question 1Not answered

The radiator in a cooling system
1. stores spare coolant for the engine
2. regulates when coolant begins to flow
3. transfers heat from the coolant into the passing air
4. drives the coolant around the circuit
Correct answer: transfers heat from the coolant into the passing air

Hot coolant passes through thin finned tubes with air flowing over them, so the heat leaves the liquid and enters the air. The large surface area is the whole point of the design.

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Question 2Not answered

On most modern fuel-injected vehicles, the fuel pump is located
1. bolted to the cylinder head
2. attached to the radiator
3. inside the air filter housing
4. inside the fuel tank
Correct answer: inside the fuel tank

Mounting the pump inside the tank keeps it submerged in fuel, which cools it and reduces the chance of vapor lock, and it also carries the fuel level sender.

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Question 3Not answered

Dim headlights at idle that brighten as engine speed increases suggest
1. worn tires
2. a weak or failing alternator
3. a clogged catalytic converter
4. a stuck thermostat
Correct answer: a weak or failing alternator

An alternator's output rises with engine speed; if it is barely keeping up, low idle speed exposes the shortfall first and the lights firm up once revs climb.

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Question 4Not answered

A spark plug's function is to
1. measure the pressure inside the cylinder
2. seal the top of the combustion chamber
3. inject fuel into the intake stream
4. ignite the compressed air and fuel mixture
Correct answer: ignite the compressed air and fuel mixture

High voltage from the coil jumps the plug's gap, and that arc lights the compressed mixture at the moment the piston nears the top of its travel.

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Question 5Not answered

A hacksaw is designed to cut
1. framing timber
2. masonry block
3. metal
4. laminated glass
Correct answer: metal

Its fine hardened teeth and tensioned blade suit metal bar, pipe, and bolts. The finer the teeth, the thinner the material it can cut without snagging.

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Question 6Not answered

A screw head with a six-pointed star-shaped recess requires a
1. socket wrench
2. flathead screwdriver
3. hex key
4. Torx driver
Correct answer: Torx driver

Torx fasteners use a distinctive six-point star recess designed to resist the driver camming out under high torque, common on automotive trim and electronics.

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Question 7Not answered

A serpentine belt typically drives
1. the camshaft in time with the crankshaft
2. accessories such as the alternator and water pump
3. the front wheels by way of the differential
4. the oil pump inside the crankcase
Correct answer: accessories such as the alternator and water pump

One long belt winds around several pulleys to run the alternator, water pump, power steering, and air conditioning. It is not the timing belt, which is a separate belt driving the camshaft and whose failure is far more serious.

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Question 8Not answered

A fuse in a vehicle's electrical system exists to
1. reduce the voltage reaching a device
2. store current for high-demand moments
3. open the circuit before excess current damages the wiring
4. connect the circuit to the body of the vehicle
Correct answer: open the circuit before excess current damages the wiring

The fuse element is the deliberate weak point, melting before the harness can overheat. A fuse that keeps blowing signals a fault to find, not a larger fuse to fit.

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Question 9Not answered

Before striking an arc with a stick welder, it is essential to first
1. preheat the metal with a torch
2. put on a welding helmet with the correct shade of lens
3. apply flux to the joint
4. file the electrode to a point
Correct answer: put on a welding helmet with the correct shade of lens

The arc produces intense ultraviolet light that can burn the eyes in seconds, so proper eye and face protection must be in place before the arc is ever struck.

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Question 10Not answered

The fuel pump's job is to
1. filter dirt out of the fuel
2. mix the fuel with the incoming air stream
3. return unused fuel to the tank
4. move fuel from the tank to the engine
Correct answer: move fuel from the tank to the engine

On an injected engine the pump usually sits inside the tank and delivers fuel to the injectors under high pressure. Filtering is the filter's job, further along the line.

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Question 11Not answered

Inside a torque converter, fluid is used to
1. transmit engine power to the transmission without a rigid mechanical link
2. lubricate the wheel bearings
3. cool the engine's cylinder head
4. operate the power brakes
Correct answer: transmit engine power to the transmission without a rigid mechanical link

The converter's impeller, driven by the engine, flings fluid at a turbine connected to the transmission, coupling the two without a solid connection, which lets the engine idle while stopped in gear.

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Question 12Not answered

In an older ignition system, the distributor
1. routes the spark to the correct cylinder at the correct moment
2. generates the high voltage the plugs need
3. distributes fuel evenly between the cylinders
4. regulates the charging voltage coming from the alternator
Correct answer: routes the spark to the correct cylinder at the correct moment

A rotor turning inside the cap passes the coil's output to each plug lead in firing order. Modern engines drop the distributor and give each cylinder its own coil under computer control.

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Question 13Not answered

The radiator cap on a modern cooling system
1. holds pressure in the system to raise the coolant's boiling point
2. lets air into the system as the engine cools
3. seals the system completely under every condition
4. controls when coolant flows to the radiator
Correct answer: holds pressure in the system to raise the coolant's boiling point

Raising the pressure raises the temperature at which coolant boils, giving a margin above normal running temperature. The cap also has a relief valve that vents to the overflow bottle, which is why removing it from a hot engine is dangerous. Controlling flow is the thermostat's job.

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Question 14Not answered

A tyre worn much more heavily on one edge than the other suggests
1. over-inflation of the tyre
2. an alignment problem
3. a slipping clutch
4. a failing wheel bearing
Correct answer: an alignment problem

Wear on one shoulder means the wheel is not meeting the road squarely, which is a camber or toe fault. Over-inflation wears the centre of the tread and under-inflation wears both edges evenly.

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Question 15Not answered

A torque converter is found in a vehicle with
1. a manual transmission
2. an automatic transmission
3. a diesel engine only
4. four-wheel drive only
Correct answer: an automatic transmission

The torque converter is a fluid coupling that does the automatic's equivalent of a clutch, letting the engine idle while the vehicle stands still in gear. A manual uses a friction clutch instead.

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Question 16Not answered

Balancing a wheel corrects
1. vibration that appears at higher speeds
2. the vehicle pulling to one side
3. a squeal when the brakes are applied
4. a knocking noise over rough ground
Correct answer: vibration that appears at higher speeds

Small weights are added so the wheel's mass is evenly distributed; without them a heavy spot sets up a shake that grows with speed. Pulling to one side is an alignment problem, and knocking over bumps is usually suspension.

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Question 17Not answered

A bolt that will not thread into a nut smoothly, binding and feeling gritty partway in, most likely has
1. a coating of oil on the threads
2. the wrong length for the application
3. damaged or cross-threaded threads
4. been over-torqued previously
Correct answer: damaged or cross-threaded threads

Threads that have been started crooked, or that were nicked or corroded, no longer follow their intended helical path, so the mating nut binds and grinds instead of turning freely.

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Question 18Not answered

Selecting a lower gear gives the vehicle
1. more top speed and less torque
2. the same torque while using rather less fuel
3. more torque at the wheels and less top speed
4. less torque and less speed together
Correct answer: more torque at the wheels and less top speed

Gearing trades one for the other: low gear multiplies torque for pulling away or climbing, high gear trades that torque for road speed. The same principle governs a bicycle's gears.

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Question 19Not answered

The ignition coil in a vehicle
1. steps the supply voltage down before the plugs
2. stores current to help start the engine
3. decides which cylinder fires next
4. steps battery voltage up to many thousands of volts
Correct answer: steps battery voltage up to many thousands of volts

A spark will not jump the plug gap at 12 volts, so the coil acts as a step-up transformer producing tens of thousands of volts in a brief pulse. Choosing the cylinder is the distributor's or the engine computer's job.

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Question 20Not answered

A boxer or flat engine has its cylinder banks arranged
1. in a V at 90 degrees
2. stacked one above the other
3. in a circle around a single crank throw
4. horizontally opposed at 180 degrees
Correct answer: horizontally opposed at 180 degrees

In a boxer layout, pistons on opposite banks move outward and inward together like boxers trading punches, which keeps the engine low and naturally balanced.

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Question 21Not answered

Compared with a gasoline engine of similar size, a diesel engine typically runs
1. without any crankshaft
2. without a cooling system
3. a lower compression ratio
4. a much higher compression ratio
Correct answer: a much higher compression ratio

Diesels rely on compression alone to ignite the fuel, so they are built with far higher compression ratios than spark-ignited gasoline engines, which would otherwise pre-ignite.

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Question 22Not answered

Countersinking a screw means
1. drilling a hole slightly smaller than the screw
2. cutting a tapered recess so the head sits flush or below the surface
3. driving the screw in at an angle for extra grip
4. sealing the head with filler once it is driven
Correct answer: cutting a tapered recess so the head sits flush or below the surface

A countersink bit cuts a cone matching the screw head so nothing protrudes above the surface. The smaller hole described in the second choice is a pilot hole, a different step.

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Question 23Not answered

The pilot hole for a wood screw should be about the diameter of
1. the screw measured across its outer threads
2. the screw's solid core, not counting the threads
3. the screw's head
4. twice the screw's thickness
Correct answer: the screw's solid core, not counting the threads

The threads need solid wood to bite into, so the hole should clear only the shank. Drilling to the outside thread diameter leaves nothing for the screw to grip and it will spin without pulling the joint tight.

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Question 24Not answered

A spark plug gap that is too wide will most likely cause
1. a spark that arrives too early in the cycle
2. a weak spark and misfiring under load
3. the engine to run at a lower temperature
4. excessive oil consumption
Correct answer: a weak spark and misfiring under load

The wider the gap, the more voltage is needed to jump it, and under load the coil may not manage it, so the cylinder misfires. Gap affects spark strength, not spark timing, which is set separately.

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Question 25Not answered

A masonry bit is specifically designed to drill into
1. softwood only
2. plastic pipe only
3. sheet aluminum only
4. concrete, brick, and stone
Correct answer: concrete, brick, and stone

Masonry bits have a hardened carbide tip shaped to chip and grind through brittle materials like concrete and brick rather than shear through them the way a wood bit does.

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The ASVAB has no pass mark. Arithmetic Reasoning, Word Knowledge, Paragraph Comprehension and Mathematics Knowledge make up your AFQT percentile.

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