ASVAB Automotive Information Practice Test 243117 Results

Your Results Global Average
Questions 5 5
Correct 0 3.33
Score 0% 67%

Review

1

Ignition timing is measured in number of degrees:

59% Answer Correctly

before top dead center

after bottom dead center

after top dead center

before bottom dead center


Solution

Ignition timing defines the point in time at the end of the compression stroke that the spark plug fires. Measured in number of degrees before top dead center (BTDC), the exact point that the spark plugs initiate combustion varies depending on the speed of the engine. The timing is advanced (the spark plugs fire a few more degrees BTDC) when the engine is running faster and retarded when it's running slower.


2

Engine oil viscosity is rated using the format XW-XX with the number preceding the W indicating viscosity at __________ ℉ and the XX indicating viscosity at __________ ℃.

65% Answer Correctly

0, 0

100, 0

100, 100

0, 100


Solution

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 ℃.


3

What function does a two-stroke cycle engine perform on the second stroke?

51% Answer Correctly

compression and combustion

fuel intake and exhaust

combustion and exhaust

fuel intake and compression


Solution

The two strokes of a two-stroke cycle engine are fuel intake and compression then combustion and exhaust.


4

The primary purpose of the muffler is to:

75% Answer Correctly

reclaim unburned fuel

quiet exhaust

cool the exhaust

remove harmful gases from the exhaust


Solution

The muffler follows the catalytic converter and absorbs sound to help quiet load exhaust. It is followed by the exhaust pipe which is the final exit point for exhaust gas from the vehicle.


5

Which of the following cylinder arrangement would be most common in an eight cylinder engine?

79% Answer Correctly

inline

V-type

opposed

vertical


Solution

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.