Question 1

Technician A says that diesel engines have compression ratios that are about twice as high as those found in gas engines. Technician B says that diesel engines require less maintenance than gasoline engines. Who is right?
A)Technician A only
B)Technician B only
C)Both A and B
D)Neither A nor B

Accepted Answer

Technician A is correct, as diesel engines typically have higher compression ratios than gasoline engines. However, Technician B is incorrect, as diesel engines actually require more maintenance than gasoline engines due to their more complex fuel injection systems and the need for regular maintenance of the diesel particulate filter.

Question 2

List three functions that a flywheel performs.

Accepted Answer

The answer of List three functions that a flywheel performs....

Question 3

A six cylinder engine has a 1 5 3 6 2 4 firing order. Technician A says that after cylinder number 1 begins its intake stroke, the crankshaft will have to travel 240° before cylinder number 3 begins its intake stroke. Technician B says that when cylinders number 3 and 4 are at TDC, cylinders number 5 and 2 are at BDC. Who is right?
A)Technician A only
B)Technician B only
C)Both A and B
D)Neither A nor B

Accepted Answer

In a six-cylinder engine with a firing order of 1 5 3 6 2 4, the crankshaft completes a 720° rotation to complete a cycle for all cylinders. Since there are six cylinders, each cylinder fires every 120° (720°/6). Therefore, after cylinder number 1 begins its intake stroke, the crankshaft will indeed have to travel 240° before cylinder number 3 begins its intake stroke (120° for cylinder 5's firing event, then another 120° to cylinder 3's firing event), making Technician A correct. Technician B's statement is incorrect because when cylinders 3 and 4 are at TDC, it does not necessarily mean that cylinders 5 and 2 are at BDC due to the engine's firing order and the positions of the pistons in their respective cycles.

Question 4

Technician A says that the Otto-cycle gasoline engine has four strokes per cycle. Technician B says that the crankshaft makes four revolutions during the four stroke cycle. Who is right?
A)Technician A only
B)Technician B only
C)Both A and B
D)Neither A nor B

Accepted Answer

The Otto-cycle gasoline engine indeed has four strokes per cycle: intake, compression, power, and exhaust. However, the crankshaft makes only two revolutions during these four strokes, not four as Technician B suggests.

Question 5

An eight-cylinder engine has a 1 8 4 3 6 5 7 2 firing order. Technician A says that cylinder number 3 is cylinder number 1's companion. Technician B says that cylinder number 5 is cylinder number 8's companion. Who is right?
A)Technician A only
B)Technician B only
C)Both A and B
D)Neither A nor B

Accepted Answer

The answer of An eight-cylinder engine has a 1 8...

Question 6

Technician A says that the intake and exhaust valves are both closed during most of the power stroke. Technician B says that the intake and exhaust valves are both closed during most of the compression stroke. Who is right?
A)Technician A only
B)Technician B only
C)Both A and B
D)Neither A nor B

Accepted Answer

Both technicians are correct. During the power stroke, the intake and exhaust valves are closed to allow the combustion gases to expand and push the piston down. Similarly, during the compression stroke, both valves are closed to compress the air-fuel mixture before ignition.

Question 7

What is a complete engine assembly called?

Accepted Answer

The answer of What is a complete engine assembly called?...

Question 8

What does OHC mean?

Accepted Answer

The answer of What does OHC mean?...

Question 9

What is the ratio called that compares the volume of the air space above the piston at TDC and BDC?

Accepted Answer

The answer of What is the ratio called that compares...

Question 10

Technician A says that an in-line six cylinder engine is usually longer and heavier than a V8 engine of the same displacement. Technician B says that there are twice as many teeth on the crankshaft sprocket as there are on the camshaft sprocket. Who is right?​
A)Technician A only
B)Technician B only
C)Both A and B
D)Neither A nor B

Accepted Answer

In-line six cylinder engines are typically longer than V8 engines of the same displacement because they have six cylinders in a straight line rather than the V-shaped arrangement of a V8. However, Technician B's statement about the number of teeth on the sprockets is not relevant to the question and therefore is not correct or incorrect.

Question 11

What is the movement of the piston from top dead center (TDC) to bottom dead center (BDC) called?

Accepted Answer

The answer of What is the movement of the piston...

Question 12

How many times in 1 second will a valve open in an engine running at 6000 rpm?

Accepted Answer

The answer of How many times in 1 second will...

Question 13

What type of engine is a compression ignition engine?

Accepted Answer

The answer of What type of engine is a compression...

Question 14

Technician A says that "blowby" consists of gases that leak past the valves. Technician B says that blowby reduces the pressure in the crankcase. Who is right?
A)Technician A only
B)Technician B only
C)Both A and B
D)Neither A nor B

Accepted Answer

Blowby actually consists of gases that leak past the piston rings into the crankcase, not past the valves as Technician A suggests. Additionally, blowby increases pressure in the crankcase rather than reducing it, contrary to Technician B's statement.

Question 15

Technician A says that the purpose of the flywheel is to control the twisting of the crankshaft. Technician B says that the purpose of the vibration damper is to help provide a continuous flow of power. Who is right?
A)Technician A only
B)Technician B only
C)Both A and B
D)Neither A nor B

Accepted Answer

The purpose of the flywheel is to store rotational energy to smooth out the power delivery and help maintain the engine's rotation when the cylinders are not firing. The vibration damper, also known as a harmonic balancer, is designed to reduce torsional vibration on the crankshaft, not to provide a continuous flow of power.

Question 16

What causes ignition to occur in a diesel engine?

Accepted Answer

The answer of What causes ignition to occur in a...

Question 17

Where would an L-head engine be found today?

Accepted Answer

The answer of Where would an L-head engine be found...

Question 18

What are the normal ranges of compression ratios for the following?
​
Otto-cycle engine ______:1
​
​diesel-cycle _______:1​

Accepted Answer

The answer of What are the normal ranges of compression...

Question 19

What are four other names for a core plug?

Accepted Answer

The answer of What are four other names for a...

Question 20

In a four stroke, four cylinder engine, how many degrees must the crankshaft turn before the next cylinder in the firing order is fired?

Accepted Answer

The answer of In a four stroke, four cylinder engine,...

Quiz 1: Engine Operation

Technician A says that diesel engines have compression ratios that are about twice as high as those found in gas engines. Technician B says that diesel engines require less maintenance than gasoline engines. Who is right?

List three functions that a flywheel performs.

Technician A says that the Otto-cycle gasoline engine has four strokes per cycle. Technician B says that the crankshaft makes four revolutions during the four stroke cycle. Who is right?

An eight-cylinder engine has a 1 8 4 3 6 5 7 2 firing order. Technician A says that cylinder number 3 is cylinder number 1's companion. Technician B says that cylinder number 5 is cylinder number 8's companion. Who is right?

Technician A says that the intake and exhaust valves are both closed during most of the power stroke. Technician B says that the intake and exhaust valves are both closed during most of the compression stroke. Who is right?

What is a complete engine assembly called?

What does OHC mean?

What is the ratio called that compares the volume of the air space above the piston at TDC and BDC?

Technician A says that an in-line six cylinder engine is usually longer and heavier than a V8 engine of the same displacement. Technician B says that there are twice as many teeth on the crankshaft sprocket as there are on the camshaft sprocket. Who is right?

What is the movement of the piston from top dead center (TDC) to bottom dead center (BDC) called?

How many times in 1 second will a valve open in an engine running at 6000 rpm?

What type of engine is a compression ignition engine?

Technician A says that "blowby" consists of gases that leak past the valves. Technician B says that blowby reduces the pressure in the crankcase. Who is right?

Technician A says that the purpose of the flywheel is to control the twisting of the crankshaft. Technician B says that the purpose of the vibration damper is to help provide a continuous flow of power. Who is right?

What causes ignition to occur in a diesel engine?

Where would an L-head engine be found today?

What are the normal ranges of compression ratios for the following? Otto-cycle engine :1 diesel-cycle _:1

What are four other names for a core plug?

In a four stroke, four cylinder engine, how many degrees must the crankshaft turn before the next cylinder in the firing order is fired?

Quiz 1: Engine Operation

Technician A says that diesel engines have compression ratios that are about twice as high as those found in gas engines. Technician B says that diesel engines require less maintenance than gasoline engines. Who is right?

List three functions that a flywheel performs.

Technician A says that the Otto-cycle gasoline engine has four strokes per cycle. Technician B says that the crankshaft makes four revolutions during the four stroke cycle. Who is right?

An eight-cylinder engine has a 1 8 4 3 6 5 7 2 firing order. Technician A says that cylinder number 3 is cylinder number 1's companion. Technician B says that cylinder number 5 is cylinder number 8's companion. Who is right?

Technician A says that the intake and exhaust valves are both closed during most of the power stroke. Technician B says that the intake and exhaust valves are both closed during most of the compression stroke. Who is right?

What is a complete engine assembly called?

What does OHC mean?

What is the ratio called that compares the volume of the air space above the piston at TDC and BDC?

Technician A says that an in-line six cylinder engine is usually longer and heavier than a V8 engine of the same displacement. Technician B says that there are twice as many teeth on the crankshaft sprocket as there are on the camshaft sprocket. Who is right?​

What is the movement of the piston from top dead center (TDC) to bottom dead center (BDC) called?

How many times in 1 second will a valve open in an engine running at 6000 rpm?

What type of engine is a compression ignition engine?

Technician A says that "blowby" consists of gases that leak past the valves. Technician B says that blowby reduces the pressure in the crankcase. Who is right?

Technician A says that the purpose of the flywheel is to control the twisting of the crankshaft. Technician B says that the purpose of the vibration damper is to help provide a continuous flow of power. Who is right?

What causes ignition to occur in a diesel engine?

Where would an L-head engine be found today?

What are the normal ranges of compression ratios for the following? ​ Otto-cycle engine ______:1 ​ ​diesel-cycle _______:1​

What are four other names for a core plug?

In a four stroke, four cylinder engine, how many degrees must the crankshaft turn before the next cylinder in the firing order is fired?

Technician A says that an in-line six cylinder engine is usually longer and heavier than a V8 engine of the same displacement. Technician B says that there are twice as many teeth on the crankshaft sprocket as there are on the camshaft sprocket. Who is right?

What are the normal ranges of compression ratios for the following? Otto-cycle engine :1 diesel-cycle _:1