The document describes the four strokes of a diesel engine: intake, compression, power, and exhaust. In the intake stroke, air enters the cylinder as the piston moves down. In the compression stroke, both valves remain closed and the piston compresses the air. In the power stroke, fuel is injected and ignites when the piston reaches top dead center, pushing the piston back down. Finally, in the exhaust stroke, the exhaust valve opens and waste gases are expelled as the piston moves back up. The document also lists key engine components like the head, camshaft, piston, connecting rod, and crankshaft.

1. prepared by: R.V.Varmoraprepared by: R.V.Varmora

2. Intake Stroke:
• Piston moves from TDC to BDC
creating vacuum in the cylinder
• Intake valve opens allowing only
air to enter the cylinder and
exhaust valve remains closed
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3. Compression Stroke
• Both valves stay closed.
• Piston moves from BDC to TDC.
• Compressing air to 22:1
compressing the air to this extent.
• Increases the temperature inside the
cylinder to above 1000 degree F.
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4. Power Stroke
•Both valves stay closed
•When the piston is at the end of
compression stroke(TDC) the injector
sprays a mist of diesel fuel into the
cylinder.
•When hot air mixes with diesel fuel
an explosion takes place in the cylinder.
•Expanding gases push the piston
from TDC to BDC
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5. Exhaust Stroke
• Piston moves from BDC to
TDC.
• Exhaust valve opens and the
exhaust gases escape.
• Intake valve remains closed.
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6. Components 4 Stroke Engine
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7. • Head- a platform
containing most of the
parts of the combustion
chamber.
• Camshaft- a round shaft
with lobes, that rotates to
open and close the fuel
and exhaust valves.
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8. • Piston- the part of the
engine that moves up and
down in the cylinder
converting the gasoline into
motion
• Connecting Rod- links the
piston to the crankshaft.
• Crankshaft- converts the
up and down motion of the
piston into a turning, or
rotating motion
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9. 4 STROKE DIESEL ENGINE
• This is a simplified model of a single cylinder Diesel
engine to show the principal parts, their relationships to
each other and how the engine works.
• It is not based on any real engine, but is generally
representative of real engines. Most real engines are
made up of several of this unit sharing a single flywheel
and cam shaft drive e.g. Three, four and six cylinder
engines.
• Many minor details and some components are left out
for clarity, for example the bearings, exhaust pipe
silencer, air intake filter and the fuel injection pump.prepared by: R.V.Varmoraprepared by: R.V.Varmora

10. Intake Valve
Valve Cover
Intake Port
Head
Coolant
Engine Block
Oil Pan
Oil Sump
Crankshaft
Camshaft
Exhaust Valve
Spark Plug
Exhaust Port
Piston
Connecting Rod
Rod Bearings
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11. The Names of the Main Moving parts
Piston
Connecting
Rod
Gudgeo
n Pin
Crank-
Shaft
Cam-
Shafts
Valv
es
Fly-
Wheel
Piston
Ring
Valve
Spring
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12. prepared by: R.V.Varmoraprepared by: R.V.Varmora