engine tech
Carburetor
A device for automatically mixing fuel in a proper proportion with air to produce a combustible gas.
Acceleration Well
A reservoir of fuel, located inside the nozzle, for use during rapid acceleration.
Lower
Since blade tip speed is a function of blade length and engine rpm, longer blades require ____________ engine speeds.
Venturi
What is a restriction in a passage, which causes incoming air to increase in velocity called?
To maintain a constant level of fuel in the float bowl
What is the purpose of the carburetor float?
They should be discarded and replaced with a new filter
What should be done to dry type air filter elements when they become dirty?
Centrifugal (mechanical)
What type of governor utilizes pivoting flyweights?
Updraft
Which type of carburetor would normally require a smaller air passage than the other two types?
Load Adjustment
A needle that regulates the amount of fuel entering the main nozzle.
Fuel & Air
11. A carburetor's primary function in to mix proper proportions of _________________________ to operate the engine.
diaphragm
A flexible partition or wall separating two cavities.
Primer
A hand operated plunger, which, when depressed, forces additional fuel through the main nozzle prior to starting a cold engine.
Natural Draft
A type of carburetor that has the air flowing horizontally into the manifold.
Downdraft
A type of carburetor that is placed high on the engine, and has the air flowing downward into the manifold.
Updraft
A type of carburetor that is placed low on the engine, and has the air flowing upward into the manifold.
Manual
A type of throttle control that consists of mechanical linkage or a flexible cable, which is used to open and close the throttle valve.
Governor
A type of throttle control that uses a mechanical, hydraulic, or electrical device that controls and regulates speed.
choke
A valve that is placed in a carburetor air inlet to restrict the volume of air admitted.
Vacuum
A(n) _______________ type of governor is usually used on farm and industrial engines.
Oil Wetted
A(n) ___________________ type of air cleaner element can be used again by washing it in soapy water.
Vent
A(n) ________________________ in the float bowl is used to equalize the air pressure above the fuel in the float bowl and the air pressure entering the carburetor.
Updraft
Air velocity must be highest in the _______________ carburetor.
Absolute Vacuum
An ____________________ is any area completely free of air or atmospheric pressure.
Vacuum
Any pressure less than atmospheric pressure.
needle valve
As fuel is used from the float bowl, the float lowers and unseats a(n) __________________ which lets fuel enter the bowl.
atmospheric pressure
As soon as the intake valve opens or the intake port is uncovered in a gas engine, _________________ forces air through the carburetor and manifold to fill that vacuum.
richer
As the air filter fills with dirt, the air-fuel mixture will become
Hunting
Centrifugal governor ______________ is when the engine speeds up and slows down repeatedly under a constant load condition.
Manifold vacuum
Diaphragm carburetors are operated by ____________________________.
Inoperative
During idle and fast idle conditions, the main discharge nozzle is __________________________.
25
For average applications such as normal yard lawn mowing, the air cleaner should be cleaned every __________ hours per season.
Vaporized
Gasoline must be ________________ by the carburetor.
Every time the engine is serviced or repaired
How often should an engine air cleaner be examined?
Spring
If an engine is designed to run at a constant speed, the speed is adjusted with the governor ___________.
Upstroke
In a diaphragm type carburetor on two-cycle engines, the fuel is drawn into the crankcase during the upstroke or downstroke of the piston?
Greatest
In a venturi, air pressure is greatest where velocity is ____________________.
Idle Discharge
In diaphragm carburetor operation, during intermediate speeds, fuel flows from the _______________________ ports only.
Air Vane Centrifugal Vacuum
List the three types of governors discussed in the chapter.
Neoprene Brass
Needle valve points in the carburetor float chamber are usually made from one of two materials. The two materials are what?
15 to 1
Normal air-fuel mixture by weight is what ratio?
Open the throttle valve
On a governor installation, the governor spring is attached to the throttle lever. The governor spring is intended to do what?
Spring tension
On an air vane governor, controlling speed is accomplished by balancing air pressure with ________________.
The float level
On some carburetors, the amount of fuel that enters the main discharge nozzle is regulated by ___________________.
Starting of the engine
Richest air-fuel mixture takes place during _________________.
Downdraft
The ____________________ carburetor can provide larger volumes of fuel for high speed and power requirements.
Acceleration Well
The ____________________________ stores fuel for use during rapid acceleration.
Stability
The ability of a governor to maintain a preset speed without fluctuating is called __________________.
Stability
The ability to maintain a desired engine speed without fluctuating.
Idling
The acceleration well fills when the engine is _____________________.
pleated
The air filter that is similar to air filters used in modern automobiles is the ______ paper type.
Flywheel
The air vane governor is operated by the stream of air created by the ____________ cooling fins.
Choke
The carburetor ________________ is a round disc mounted on a shaft located at the intake end of the carburetor.
Nearest the intake end of the carburetor
The choke valve in the carburetor is always located where?
Main discharge Nozzle
The diaphragm in a carburetor forces fuel through the ____________________________.
Part throttle
The economizer circuit is design to retard fuel flow to the engine at ____________________.
Flat pleated paper cartridge filter
The newest type of air cleaner for small gasoline engines is the ______________.
Sensitivity
The percent of engine speed change required to produce a corrective movement of the fuel control mechanism is called ______________.
Sensitivity
The percent of speed change required to produce a corrective movement of the fuel control mechanism.
Increase the air-fuel ratio
The primary purpose of air bleeds is to _______________________.
Air Pressure
The primer on a float-type carburetor pumps ___________________ into the float bowl forcing fuel up the nozzle.
Shaking it with the external side down
The proper way to clean an air filter cartridge of the pleated paper type is what?
Detergent & Water
The safest solution in which to wash an air cleaner plastic foam element is what?
15
The usual normal air-fuel mixture is a ratio of ____________ part(s) of air to 1 part of fuel.
Throttle
This controls speed by regulating the amount of fuel delivered to the engine.
Air Cleaner
This is a device that is used to clean incoming air.
Venturi
This is a restriction in a passage, which causes air to move with an increased velocity.
Float
This is a small, sealed vessel made of brass or plastic.
Economizer Circuit
This is designed to retard fuel flow to the engine at part throttle.
Atmospheric Pressure
This is the weight of air at sea level.
Oil Wetted Dry types Dual-element
What are the three types of air cleaners that are widely used in small gasoline engines?
Maintain Speed Prevent Over-speeding Limit high & low speeds
What are three basic functions that governors are designed to serve?
Dual-element
When an engine is designed for use in greater than normal dusty/dirty conditions, a(n) ________________ air filter is installed.
Richer
When closed, does the choke provide a leaner or richer air-fuel mixture, which is needed to start a cold engine?
Use more fuel Lose power Accumulate carbon
When the air filter becomes dirty, the engine will do what?
Dry type
__________________ air cleaners pass the airstream through treated paper, felt, fiber, or flocked screen.
