### 4 Stroke Engine cycle [Autosaved]x

```Part 1
7Ub8
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A cylinders displacement is the volume of the
cylinder when the piston is at BDC.
It is the sum of the displacement of each
cylinder.
It is defined as the volume of air/fuel mixture
an engine can draw in.
Ex: 700 cc (cubic centimetres)
1000 cc = 1 Litre
Example : Vehicle has 4 cylinders
: Each cylinder has a volume of
700cc
: 700cc X 4 = 2800cc
: 2800cc = 2.8 Litre
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Torque is the term used to describe a
rotating force.
More torque generally means a car can
accelerate faster
Torque is the actual reading of how “hard”
and with how much “Force” the engine turns.
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Horsepower: 1 hp = 33,000 lb-ft / min
One horsepower is the ability to lift 33000
pounds one foot in one minute
The horsepower specification for an engine tells
you how much power the engine can produce.
Horsepower is the rate at which the engine does
work
Formula:
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HORSEPOWER = (TORQUE * RPM) / 5252
A engine that makes 300 pound-feet of
torque at 4,000 RPM produces
[(300 x 4,000) / 5,252] 228 horsepower at
4,000 RPM
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Torque being how hard you can pound away
on bicycle pedals
Horsepower being how fast you can spin the
bicycle pedals.
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What
What
What
What
is engine displacement?
is horsepower?
is Torque?
are the different parts of an engine?
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_ohQ&feature=related
Part 2
The four-stroke engine
Spark plug
Exhaust valve
Inlet valve
Cylinder
Piston
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Is a can-shaped part closely fitted inside the
cylinder.
Piston rings consist of compression rings and
oil rings.
Crankshaft takes the up-down motion of the
piston and convertors it to a rotation motion
Connecting rod connects the piston to the
crankshaft.
The 4 Stroke engine cycle consist of these:
1) Intake
180degree
2) Compression
180 degree
3) Power/ Combustion
180 degree
4) Exhaust
180 degree
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Total engine revolution
720 degree
One complete engine cycle consists of 4
engine strokes.
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The Intake Stroke consist of the piston
travelling down.
Intake valves are open to allow Air/Fuel
mixture to come into the combustion
chamber.
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Intake plastic ducts
Intake manifolds
-
Fuel injectors are electronically controlled
valves that spray fuel to mix with air.
Creating that air fuel mixture
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It is an electrical device that fits into
the cylinder head and ignites air fuel
mixtures.
The four-stroke engine
Inlet valve
open
Exhaust
valve
closed
INTAKE STROKE
The four-stroke engine
Inlet valve
open
Exhaust
valve closed
Piston down
INTAKE STROKE
The four-stroke engine
Fuel in
Exhaust
valve
closed
Inlet valve
open
Piston down
INTAKE STROKE
The four-stroke engine
Fuel in
Exhaust
valve
closed
Inlet valve
open
Piston down
INTAKE STROKE
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What
What
What
What
is
is
is
is
the purpose of the intake system?
the purpose of the spark plug?
the purpose of the fuel injector?
happening during the intake stroke?
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Part 3
TM
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Compression stroke consist of the piston
travelling back up.
Both intake and exhaust valves are closed
Air fuel mixture is now being compressed
The four-stroke engine
Exhaust
valve
closed
Inlet valve
closed
COMPRESSION STROKE
Piston up
The four-stroke engine
Inlet valve
closed
Exhaust
valve closed
Piston up
COMPRESSION STROKE
The four-stroke engine
Inlet valve
closed
Exhaust
valve
closed
Piston up
COMPRESSION STROKE
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The piston is now at the TDC
Spark plug ignites, creating a spark that
ignites the compressed air fuel mixture.
Explosion is created and the piston is forced
back down.
Hence the Power stroke
Both valves are still closed
The four-stroke engine
Inlet valve
closed
Exhaust
valve
closed
BANG
POWER STROKE
The four-stroke engine
Inlet valve
closed
Exhaust
valve
closed
Piston down
powerfully
POWER STROKE
The four-stroke engine
Inlet valve
closed
Exhaust
valve
closed
POWER STROKE
Piston down
powerfully
The four-stroke engine
Inlet valve
closed
Exhaust
valve
closed
POWER STROKE
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Exhaust stroke the piston is travelling up
Exhaust valve is open
Intake valve is Closed
Exhaust gases being pushed out by piston
The four-stroke engine
Inlet valve
closed
Exhaust
valve closed
EXHAUST STROKE
The four-stroke engine
Inlet valve
closed
Exhaust valve
open
Exhaust gases
out
Piston up
EXHAUST STROKE
The four-stroke engine
Inlet valve
closed
Exhaust valve
open
Exhaust gases
out
Piston up
EXHAUST STROKE
The four-stroke engine
Inlet valve
open
Exhaust valve
closed
INTAKE STROKE
And so the
cycle
continues!!
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The exhaust system is needed to provide a
pathway for exhaust fumes to be filtered and
to reduce noise.
Exhaust manifold
Catalytic convertor
Muffler
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What is the purpose of the compression
stroke and what is happening
What is the purpose of the power stroke and
what is happening?
What is happening during the exhaust stroke?
What is the purpose of the exhaust system?
Video of 4 Stroke
cycle