Chapter 72- Internal Combustion Engines Flashcards
In a compression engine the fuel is ignited by
The compressed air temperature
Diesel engine governing is accomplished by
Varying the fuel quantity
Internal combustion engines used to drive gas compression machinery and which burn natural gas operate on the _______ stroke cycle
Two or four
How is fuel in a gasoline engine delivered?
An injector
A carburetor
What is a fuels resistance to premature detonation called?
Octane rating
Four-stroke cycle valves are operated
Cams
The purpose of a spark plug
To ignite the air fuel mixture in a gasoline engine
An engine which develops one power stroke with every other turn of the crankshaft is the
Four stroke natural gas engine
Four cycle engine lubrication may be accomplished by
Pumping oil under pressure
An example of a gasoline engine which gives high torque at low speeds would be A. chainsaw B. two cycle snowmobile C. four stroke motor cross motorcycle D. two cycle lawnmower E. two cycle transit bus
C
A major difficulty encountered with a two-stroke cycle engine is
Exhausting the spent gasses from the cylinder
When does the exhaust valve open on a four cycle engine
The end of the power stroke
A four stroke ignition engine in theory has ______ the power of a two stroke engine
Half
When does the spark plug ignite the air/fuel mixture in a four stroke engine
Near the end of the compression stroke
How many ports does a simple two stroke spark ignition engine have?
2
Define cylinder scavenging
The removal of exhaust gasses from a cylinder
Compression engines
Will compress air only on the compression stroke
An injection nozzle is used to _________ the fuel in a Diesel engine
Atomize
In larger two stroke Diesel engines how is scavenging air provided
With superchargers
The injection pump of a Diesel engine is driven by the
Camshaft
Ignition in a Diesel engine is started by
Compression in the cylinder
What is a diesels engines camshaft driven by?
The crankshaft
How high might the compression ratio of a Diesel engine be
25:1
What is the purpose of a pushrods in a typical four stroke Diesel engine?
To operate a rocker arm
How might the frame of a Diesel engine be constructed?
Cast or welded
Using a compressed air starting motor is a popular method of starting a
Large stationary Diesel engine