ASVAB Automotive Information Practice Test 969536 Results

Your Results Global Average
Questions 5 5
Correct 0 3.10
Score 0% 62%

Review

1

What is the name of the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air?

62% Answer Correctly

residual ratio

combustion ratio

ignition ratio

stoichiometric ratio


Solution

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.


2

When a car engine is running, what provides electrical current to recharge the battery and power the electrical system?

84% Answer Correctly

alternator

solenoid

battery

camshaft


Solution

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.


3

Which of the following enables heat transfer from the cylinder heads to the coolant?

49% Answer Correctly

water pump

water jacket

radiator

water sleeve


Solution

A water jacket is a coolant-filled casing that allows heat transfer from the engine block and cylinder heads to the liquid coolant.


4

Which of the following is a relay that connects the battery to the starter motor when the ignition key is turned?

54% Answer Correctly

ignition coil

solenoid

actuator

alternator


Solution

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.


5

Which of the following is not a function of the oil pan?

62% Answer Correctly

screens debris from oil

cools engine oil

acts as the engine oil reservoir

feeds the oil pump


Solution

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.