Millwright level 4 INTERNAL COMBUSTION
ENGINES Exam Questions With Verified
Answers
Before performing maintenance on a recently run engine, you must:
A) Drain all oil from the crankcase
B) Check and record the hour meter
C) Disconnect all electrical, close, lock, tag and purge all gas sources
D) Contact the manufacturer
C) Disconnect all electrical, close, lock, tag and purge all gas sources
The thermal efficiency of an engine is best described as:
A) Draw in a full charge of air to produce power
B) efficiently run in a smooth and effective manner
C) change the energy in the fuel to usable heat energy and power
D) burn the fuel wit the least amount of power lost to friction
D) burn the fuel wit the least amount of power lost to friction
The Amount of air an engine is able to take into the cylinder compared with the volume of the
cylinder is called:
A)scavenging efficiency
B) cycle efficiency
C) Thermal efficiency
D) Volumetric efficiency
D) volumetric efficiency
The description of compression ratio is best described as:
A) the cylinder volume divided by the combustion chamber volume
B) the cylinder volume plus the combustion chamber volume, divided by the combustion chamber
volume
C) the cylinder volume plus the displacement volume, divided by the combustion chamber volume
D) the total displacement of the engine divided by the combustion chamber volume
B) the cylinder volume plus the combustion chamber volume, divided by the combustion chamber
volume
On a 2-stroke engine with 6 cylinders and a firing order of 1-5-3-6-2-4, the running mates would be:
A) 1-6 5-4 3-4
B) 1-3 2-4 5-6
C) 1-4 5-2 3-6
D) none of the above
D) none of the above
When comparing a diesel engine to a gas engine, the:
A) compression pressures may be twice as high or greater in a diesel engine
B) compression ratios are approximately twice as high or greater in a diesel engine
C) Diesel engine is heavier
D) All of the above
D) All of the above
When air is compressed, what are the noticeable effects?
,A) The volume increases but the temperature remains constant
B) the temperature increases, as the volume decreases
C) The pressure increases w/o a temperature increase
D) Volume has no effect on the temperature
B) the temperature increases, as the volume decreases
The SI metric system measures pressure in:
A) cubic centimeters
B) pascals
C) newtons
D) watts
B) pascals
When you are determining engine rotation using the SAE standard, you view the engine from:
A)the fan or the front of the vehicle
B) the main power end of the engine
C) the side with the flywheel on the left
D) either the flywheel or the front balancer
B) the main power end of the engine
Which type of head design has the valves in the block?
A) an I head engine
B) a wedge-type engine
C) an L head engine
D) a multi-valve-type engine
C) an L head engine
Indicated horsepower is the power at the flywheel of the engine.
True or False?
False. Indicated HP is the engine's theoretical HP.
A 2-Stroke engine completes on cycle in 720 degrees of rotation.
True or False
False. This is done in 360 degrees. 4 strokes complete their cycle in 720 degrees.
Potential energy is the energy resulting from the motion of an object.
true or false
False. Kinetic energy is the result of a moving object.
An undersquare engine is an engine with a larger stroke than bore.
True or False
True
Blowby is leakage past the rings.
, T OR F
True
Running mates are pistons that reach TDC at the same time.
T OR F
True
The basic requirement for combustion is air, spark, and compression.
T OR F
False. oxygen, fuel, ignition
The fuel must be atomized and mixed with air to be burned.
True or False
true
At the end of the exhaust stroke, the intake and exhaust vales are open at the same time.
T or F
True
A two stroke engine makes twice as much power as a four stroke engine of the same capacity.
T or F
False. 2 strokes are not twice as powerful as 4 strokes of the same displacement due to the fact that
their effective power stroke is shorter then that of a 4 stroke.
Spark ignition engines have a much lower compression ratio than diesel engines.
T or F
True
The classification for an engine with a normal operating speed of 800 RPM is a low-speed engine
T or F
False. This would be classified as a medium-speed engine.
Integral engines require proper alignment with the driven unit.
t or f
False, INTEGRAL. INTEGRATED.
What is the purpose of a Crank shaft?
To convert linear motion to rotary motion
ENGINES Exam Questions With Verified
Answers
Before performing maintenance on a recently run engine, you must:
A) Drain all oil from the crankcase
B) Check and record the hour meter
C) Disconnect all electrical, close, lock, tag and purge all gas sources
D) Contact the manufacturer
C) Disconnect all electrical, close, lock, tag and purge all gas sources
The thermal efficiency of an engine is best described as:
A) Draw in a full charge of air to produce power
B) efficiently run in a smooth and effective manner
C) change the energy in the fuel to usable heat energy and power
D) burn the fuel wit the least amount of power lost to friction
D) burn the fuel wit the least amount of power lost to friction
The Amount of air an engine is able to take into the cylinder compared with the volume of the
cylinder is called:
A)scavenging efficiency
B) cycle efficiency
C) Thermal efficiency
D) Volumetric efficiency
D) volumetric efficiency
The description of compression ratio is best described as:
A) the cylinder volume divided by the combustion chamber volume
B) the cylinder volume plus the combustion chamber volume, divided by the combustion chamber
volume
C) the cylinder volume plus the displacement volume, divided by the combustion chamber volume
D) the total displacement of the engine divided by the combustion chamber volume
B) the cylinder volume plus the combustion chamber volume, divided by the combustion chamber
volume
On a 2-stroke engine with 6 cylinders and a firing order of 1-5-3-6-2-4, the running mates would be:
A) 1-6 5-4 3-4
B) 1-3 2-4 5-6
C) 1-4 5-2 3-6
D) none of the above
D) none of the above
When comparing a diesel engine to a gas engine, the:
A) compression pressures may be twice as high or greater in a diesel engine
B) compression ratios are approximately twice as high or greater in a diesel engine
C) Diesel engine is heavier
D) All of the above
D) All of the above
When air is compressed, what are the noticeable effects?
,A) The volume increases but the temperature remains constant
B) the temperature increases, as the volume decreases
C) The pressure increases w/o a temperature increase
D) Volume has no effect on the temperature
B) the temperature increases, as the volume decreases
The SI metric system measures pressure in:
A) cubic centimeters
B) pascals
C) newtons
D) watts
B) pascals
When you are determining engine rotation using the SAE standard, you view the engine from:
A)the fan or the front of the vehicle
B) the main power end of the engine
C) the side with the flywheel on the left
D) either the flywheel or the front balancer
B) the main power end of the engine
Which type of head design has the valves in the block?
A) an I head engine
B) a wedge-type engine
C) an L head engine
D) a multi-valve-type engine
C) an L head engine
Indicated horsepower is the power at the flywheel of the engine.
True or False?
False. Indicated HP is the engine's theoretical HP.
A 2-Stroke engine completes on cycle in 720 degrees of rotation.
True or False
False. This is done in 360 degrees. 4 strokes complete their cycle in 720 degrees.
Potential energy is the energy resulting from the motion of an object.
true or false
False. Kinetic energy is the result of a moving object.
An undersquare engine is an engine with a larger stroke than bore.
True or False
True
Blowby is leakage past the rings.
, T OR F
True
Running mates are pistons that reach TDC at the same time.
T OR F
True
The basic requirement for combustion is air, spark, and compression.
T OR F
False. oxygen, fuel, ignition
The fuel must be atomized and mixed with air to be burned.
True or False
true
At the end of the exhaust stroke, the intake and exhaust vales are open at the same time.
T or F
True
A two stroke engine makes twice as much power as a four stroke engine of the same capacity.
T or F
False. 2 strokes are not twice as powerful as 4 strokes of the same displacement due to the fact that
their effective power stroke is shorter then that of a 4 stroke.
Spark ignition engines have a much lower compression ratio than diesel engines.
T or F
True
The classification for an engine with a normal operating speed of 800 RPM is a low-speed engine
T or F
False. This would be classified as a medium-speed engine.
Integral engines require proper alignment with the driven unit.
t or f
False, INTEGRAL. INTEGRATED.
What is the purpose of a Crank shaft?
To convert linear motion to rotary motion
