ARMY ASVAB GENERAL MAINTENANCE AUTOMOTIVE

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ARMY ASVAB GENERAL MAINTENANCE (AUTOMOTIVE

INFORMATION) EXAM QUESTIONS

Actual Qs and Ans - Expert-Verified Explanation -Guaranteed passing score -58 Questions and Answers

-Format: Multiple-choice / Flashcard

Question 1: Brakes

Answer:

Brakes utlize friction to slow vehicle tires. Drum brakes employ a cast iron drum that roates with the vehicle axle. When hydraulic pressure is applied to the brake assemblies at the wheels, internal pistons expand and push brake shoes outward into contact with the brake drum slowing the rotation of the axle.More powerful disc brakes operate by pinching a rotating disc betweeen two brake pads and allow for a larger surface area to contact the disc, provide more force, and are more easily cooled.

Question 2: Oil Viscosity

Answer:

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 ?.

Question 3: Alternator

Answer:

Once the engine is running, the alternator provides electrical current to recharge the battery and power the electrical system. The alternator is driven by the engine's crankshaft and produces alternating current (AC) which is then fed through a rectifier bridge to convert it to the direct current (DC) required by the electrical system. A voltage regulator controls the output of the alternator to maintain a consistent voltage (approx. 14.5 volts) in the electrical system regardless of load.

Question 4: Solenoid

Answer:

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

Question 5: Springs

Answer:

Suspension springs are made with wide gap coils of rigid steel cable and both hold the vehicle chassis up off the ground and absorb energy from wheel movement making for a smoother ride.

Question 6: Oil Pump

Answer:

The oil pump is driven by the camshaft and is responsible for pumping oil through the oil galleries (passages) that run throughout the engine. It also contains the oil filter and a pressure relief valve which prevents excessive pressure from building up in the lubrication system.

Question 7: Electric Fuel Pump

Answer:

The electric fuel pump feeds pressurized fuel through a fuel filter to the fuel injectors via the fuel rail manifold. The fuel rail contains the fuel pressure regulator which ensures that the fuel injectors receive fuel at a consistent and known rate. Excess fuel bled off by the pressure regulator returns to the fuel tank through the fuel return line.

Question 8: Cylinder Arrangement

Answer:

Cylinder number and arrangement depends on the purpose of the engine. Smaller (four and six cylinder) engines in front-wheel drive vehicles often use an inline design which orients cylinders vertically over the crankshaft and aligns them in a row. Other common orientations are a horizontal/opposed design which places cylinders flat facing each other with the crankshaft between them and a V-type design common in six and eight cylinder engines that features one cylinder head per block of cylinders oriented at a 60 to 90 degree angle to each other with the crankshaft at the bottom of the V.

Question 9: Independent Suspension

Answer:

Most modern cars use an independent suspension system on the front wheels. This setup allows each of the wheels on an axle to move independently in response to road level variations. Independent suspension offers much better handling and stability when compared to a rigid axle suspension at the

cost of being structurally weaker and more costly to maintain.

Question 10: Engine Block

Answer:

Large casing that contains the cylinders and many of the internal components of the engine

Question 11: Lighting

Answer:

The lighting system consists of interior lights, instrument panel lighting, headlights, and taillights. Like household electrical circuits, the vehicle's lighting system is protected from current spikes by fuses and circuit breakers.

Question 12: Compression Stroke

Answer:

During the compression stroke, both intake and exhaust valves are closed as the piston begins moving back up from the bottom of the cylinder (bottom dead center or BDC). This compresses the air-fuel mixture in the combustion chamber which also makes it hotter.

Question 13: Oil Pan

Answer:

The oil pan contains the engine oil reservoir of from four to six quarts of oil and feeds the oil pump through the oil pickup tube. An oil strainer floats at the top of the oil in the oil pan and screens debris from the oil before feeding it to the oil pump.

Question 14: Steering Linkage

Answer:

The steering linkage is a system of pivots and connecting parts between the steering gear and the control arms. The steering linkage transfers the motion of the steering gear output shaft to the steering arms that turn the wheels.

Question 15: Air-Fuel Mixture

Answer:

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.

Question 16: Transaxle

Answer:

A differential is designed to drive a pair of wheels while allowing them to rotate at different speeds. A transaxle is a transmission that incorporates the differential in one package. Most front-wheel drive cars use a transaxle while rear-wheel drive cars use a transmission and separate differential connected via a drive shaft. The differential is incorporated into the drive axle which splits engine power delivered by the drive shaft between the two drive wheels. All-wheel drive cars typically use a transaxle that includes an output shaft to the rear differential.

Question 17: Powertrain Control Module

Answer:

The main computer or powertrain control module (PCM) uses pre-programmed software to analyze the input received from sensors and produce output signals to adjust vehicle performance and operation.(Engine control unit (ECU) is another name for the PCM.)

Question 18: Internal Combustion

Answer:

burning of an air-fuel mixture to provide energy. It requires the presence of air, fuel, and a heat source to ignite the air-fuel mixture. In the internal combustion engine utilizing a fuel like gasoline, diesel fuel, or natural gas

Question 19: Crankshaft

Answer:

The crankshaft converts the reciprocating motion of the piston into the rotational motion that's used to power the vehicle and its components.

Question 20: Water Pump

Answer:

The water pump is driven by a belt connected to the crankshaft and ensures that coolant moves through the engine and radiator.

Question 21: Control Arms

Answer:

Control arms (upper and lower) connect a vehicle's suspension to the frame. The connection to the wheels is through ball joints which allow the control arms to turn and move up and down simultaneously.The frame connection uses bushings.