WorksheetsAg Power Midterm Exam Jan 2025
Total questions: 50
Worksheet time: 25mins
In the carburetor, the narrowing of the tube where the gas is sucked up from the bowl is known as the _________?
Bernoulli
Float
Venturi
Choke
During the Compression stroke the piston moves________
During the Power stroke the piston moves________
Where is the most common spot to find the model number on small engines?
on the valve head cover
on the flywheel
on the crankcase base
on the fuel tank
______ is the international unit of frequency equal to one cycle per second.
Milliamp
Micron
Hertz
Henry
Three methods of heat transfer are
conduction, potential, radiation
potential, kinetic, convection
conduction, kinetic, convection
conduction, convection, radiation
What are the three main engines systems
Ignition, Compression, Fuel
Intake, Compression, Exhaust
Intake, Fuel, Compression
Spark, Fuel, Compression
The connecting rod connects what two engine parts together?
Piston and Camshaft
Piston and Crankcase
Piston and Flywheel
Piston and Crankshaft
What are the egg-shaped pieces on the camshaft called?
Cam Lobs
Cam Valves
Cam retainers
Cam tappets
During which stroke does the spark plug fire and cause combustion in the cylinder?
Intake
Compression
Power
Exhaust
What is the purpose of the compression ring?
provide a seal between the piston and crankshaft
provide a seal between the piston and the cylinder
provide a seal between the cylinder and the crankshaft
provides a seal between crankshaft and crankcase
Which of the following is a function of a small engine?
To change heat energy into mechanical energy
To change kinetic energy into potential energy
To change rotary motion into vertical motion
To change reciprocal motion into circular motion
What are the purpose of the cam lobes?
to prevent oil in the cylinder
to move the valves open and closed
decroative
to seal the air-fuel mixture during compression
What theory does the ignition armature rely on to work?
Induction Theory
Bernoulli's Principle
the Venturi Effect
Four Stroke Theory
What allows gas to come into the throat of the carburetor from the fuel bowl?
Bernoulli's Principle
the Venturi effect
Induction Theory
Four-Stroke Theory
What does the idle circuit do?
allows a little fuel/air mixture to bypass the throttle plate to maintain the engine
to mix the gas and air together
makes gas come up to the carburetor from the fuel bowl
Creates a vacuum in the combustion chamber
What are the two systems for cooling an engine?
Liquid and air cooling systems
jet propulsion and injection systems
oil and vinegar cooling systems
chemical and physical systems
What is torque?
a rotating force
Pressure per square in
rotations per minute
a pulling force
Which engine type requires oil to be mixed into gas
Single cylinder
Two stroke engines
Four Stroke Engines
Auto engines
What is the number one shop safety rule?
Report all accidents to the instructor
Always wear safety glasses
No horseplaying
Know where the fire extinguishers are located
What is this ?
exhaust gasket
Sump gasket
Carburetor gasket
Head gasket
If your engine is running rich, this means?
There is more air than gas in the air/fuel mixture
There is more gas in the air in the air/fuel mixture
That the choke is closed
That the smoke coming from the engine is white
What danger does running an engine inside the shop present that requires students to open a window?
Carbon monoxide poisoning
bruising from a falling engine
a gas explosion
slipping on an oil spill
Why does the flywheel have to be so heavy?
It helps provide inertia to keep the engine going
engines are sold by the pound
it helps slow the engine to a stop
magnets are heavy and the flywheel has 1 or more
What are these
Valves
Fuel regulator
Carburetor
Rockers
What would happen if all the piston rings were aligned?
oil would get into the combustion chamber and blue smoke would appear in the exhaust
the engine would die
nothing
the engine will run smoothly
What does the idle spring do?
Keeps tension on the governor to maintain a consistent rpms at idle
nothing, its idle after all
Increases the gas when the engine is under heavy load
Decreases the gas when the engine is under heavy load
What does the governor control?
the rpms of an engine (tries to make them constant)
the choke (controls the air going into the carburetor)
The electrical current going to the spark plug
the amount of oil in the crankcase
The governor connecting rod and spring connected to what?
the throttle plate
the choke plate
the ignition amature
the oil slinger
What role does the flywheel play in the ignition system?
Provides the magnet to complete the induction theory cycle
provides the electrical current to complete the induction theory cycle
the electrical conductor to complete the induction theory cycle
it doesn't
There are __________________ rings on a small engine piston.
one
two
three
four
A lawn mower typically will have a __________________ crankshaft.
vertical
diagonal
horizontal
flat
Reducing wear between moving parts is a function of the ____________________________.
fuel system
starting system
cooling system
lubrication system
The typical cooling system on a small engine uses _____________ to transfer heat.
fins
channels
fans
vacuum
A disc- or cone-shaped object with teeth that engage the teeth on another.
Gear
Sprocket
Clutch
Hydrostatic Drive
A friction disc assembly that engages and disengages the engine flywheel to transfer power to the transmission.
Gear
Sprocket
Clutch
Hydrostatic Drive
A toothed wheel used to drive a chain.
Gear
Sprocket
Clutch
Hydrostatic Drive
Why do valves rotate as they open and close?
to clean off the carbon build up
to provide extra torque to the engine
to assist in bringing in fresh air
the springs naturally do this
