THERMAL ENGINEERING

LAB MANUAL

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LIST OF EXPERIMENTS

1. I.C ENGINES PERFORMANCE TEST (4-STROKE DIESEL ENGINE

2. I.C ENGINES HEAT BALANCE

3. ECONAMICAL SPPED TEST (4-STROKE DIESEL ENGINE)

4. PERFORMANCE TEST ON RECIPROCATING AIR COMPRESSOR

5. PORT TIMING DIAGRAM OF A 2-STROKE PETROL ENGINE

6. VALVE TIMING DIAGRAM OF A 4-STROKE DIESEL ENGINE

7.. DIS-ASSEMBLY AND ASSEMBLY OF A ENGINE.

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I.C ENGINES PERFORMANCE TEST (4-STROKE DIESEL ENGINE)

AIM:

To conduct performance test on 4-Stroke diesel engine (Single cylinder) and to

draw the following graphs.

1. B.P Vs S.F.C

2. Mechanical efficiency Vs B.P

3. B.P Vs Indicated thermal efficiency

4. B.P Vs Indicated thermal efficiency

5. Air fuel Ratio Vs B.P

6. Air fuel Ratio Vs S.F.C

THEORY:

The Test Ring consists of Four-Stroke Diesel Engine, to be tested for

performance, is connected to Rope Brake Drum with Spring Balace (Mechanical

Dynamometer) with Exhaust Gas Calorimeter. The arrangement is made for the

following measurements of the Set-up :

1) The Rate of Fuel Consumption is measured by using the pipette reading againt the

known time.

2) Air Flow is measured by Manometer connected to Air Box.

3) The different mechanical loading is achieved by operating the spring balance of

dynamometer in steps.

4) The different mechanical energy is measured by spring balance and radius of

brake drum.

5) The Engine Speed (RPM) is measured by electronic digital RPM Counter.

6) Temperature at different points is measured by electronic digital Temperature

Indicator.

7) Water Flow Rate through the engine & calorimeter is measured by Watermeter.

The whole instrumentation is mounted on a self – contained unit ready for table

operation.

PROCEDURE:

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1. Check the diesel in the diesel tank.

2. Allow diesel, start the engine by using hand cranking.

3. The engine is set to the speed of 1500 RPM.

4. Apply load from the spring balance of dynamometer.

5. Allow some time so that the speed stabilizes.

6. Now take down spring balance readings.

7. Put tank valve in to pipette position and note down the time taken for

particular quantity of fuel consumed by the engine.

8. Note down the temperature readings at different points.

9. Note down the water readings.

10. Repeat the procedure (4)&(7) for different loads.

11. Tabulate the readings as shown in the enclosed list.

12. After the experiment is over ,keep the diesel control valve at mains position.

OBSERVATIONS:

Engine

Speed

in

RPM

Spring

balance

Readings

Fuel

pipette

readings

Caloriemeter

Water

Temperature

Engine head

water

temperature

Exhaust gas

temperature

Air

inlet

Air flow

Manometer

readings in

mm of

water

Water

flow

rate

in

lpm

―F1‖

In

Kgs

―F2‖

In

Kgs

In

Ml

Time

in

Secs.

Inlet

T2°C

Outlet

T3°C

Inlet

T1°C

Outlet

T2°C

Inlet

T4°C

Outlet

T5°C T6°C

1 2(a) 2(b) 3(a) 3(b) 4(a) 4(b) 5(a) 5(b) 6(a) 6(b) 7 8 9

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CALCULATIONS

1.FUEL CONSUMPTION IN Kg/Hr

WF = dingsoftablereabColumn

dingsoftablereaaColumn

)3(

)3( x 3.06

2. ENGINE OUT PUT” BHP”:

BP= 4500

)( 2 21 rFFN KW

Where, N- Speed of engine in RPM

r—Radius of brake drum in mts =0.185 mt

F1&F2- Force indicated on spring balance in KGs

3.SPECIFIC FUEL CONSUMPTION (SFC):

SFC = BHP

WF Kg/BHP. Hr

4. FUEL HP(THERMAL HORSE POWER),

FHP= 4500 X 60

J x C x W VF

Where, Cv = Calorific value of diesel= 10000 K.Cal /Kg

J= Mechanical equivalent of heat=427 kg.m / K.Cal

5. PERCENTAGE THERMAL EFFICIENCY.

% η th = FHP

BHP x 100

6. AIR CONSUMPTION IN Kg/ Hr ‘Wa’

Wa = 0.6 x A0 x Va x 1.29 x 60 x 60

Where, Ao = Area of the orifice in m2

= 4

d2

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Where d= Dia.of the orifice in m = 0.015 mt

Va = 1]-)[( x 1000)(h 2g awm/

Where g = 9.81 m/ sce2

hm = Manometer reading in mm (column 5)

ρw = Density of water = 1000 Kg/ m3

ρa = Density of air = 1.29 Kg/ m

3

7.AIR TO FUEL CONSUMPTION RATIO.

Air to fuel consumption ratio = F

a

W

W

RESULT;

Performance test on 4-Stroke diesel engine(Single cylinder) is conducted and the

following graphs are plotted.

1. B.P Vs S.F.C

2. Mechanical efficiency Vs B.P

3. B.P Vs Indicated thermal efficiency

4. B.P Vs Indicated thermal efficiency

5. Air fuel Ratio Vs B.P

6. Air fuel Ratio Vs S.F.C

Sl.NO

Engine

RPM

―N‖

Fuel

Consumed

―Wf‖

In Kg/Hr

Air

Consumed

―Wa‖

In Kg/Hr

Air to Fuel

Ratio

―Wa / Wf‖

Engine

output

―BHP‖

Specific fuel

consumption

―SFC‖

Fuel HP

―FHP‖

Brake % η

thermal

efficiency

1

2

3

4

5

6

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I.C ENGINES HEAT BALANCE

AIM:

To conduct performance test on 4-Stroke diesel engine(Single cylinder) and to

check the heat balance of I.C engine.

THEORY:

The Test Ring consists of Four-Stroke Diesel Engine, to be tested for

performance, is connected to Rope Brake Drum with Spring Balance (Mechanical

Dynamometer) with Exhaust Gas Calorimeter. The arrangement is made for the

following measurements of the Set-up :

1) The Rate of Fuel Consumption is measured by using the pipette reading against

the known time.

2) Air Flow is measured by Manometer connected to Air Box.

3) The different mechanical loading is achieved by operating the spring balance of

dynamometer in steps.

4) The different mechanical energy is measured by spring balance and radius of

brake drum.

5) The Engine Speed (RPM) is measured by electronic digital RPM Counter.

6) Temperature at different points is measured by electronic digital Temperature

Indicator.

7) Water Flow Rate through the engine & calorimeter is measured by Wattmeter.

The whole instrumentation is mounted on a self – contained unit ready for table

operation.

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PROCEDURE:

1. Check the diesel in the diesel tank.

2. Allow diesel, start the engine by using hand cranking.

3. The engine is set to the speed of 1500 RPM.

4. Apply load from the spring balance of dynamometer.

5. Allow some time so that the speed stabilizes.

6. Now take down spring balance readings.

7. Put tank valve in to pipette position and note down the time taken for particular

quantity of fuel consumed by the engine.

8. Note down the temperature readings at different points.

9. Note down the water readings.

10. Repeat the procedure (4)&(7) for different loads.

11. Tabulate the readings as shown in the enclosed list.

12. After the experiment is over ,keep the diesel control valve at mains position.

OBSERVATIONS:

Engine

Speed

in

RPM

Spring

balance

Readings

Fuel

pipette

readings

Caloriemeter

Water

Temperature

Engine head

water

temperature

Exhaust gas

temperature

Air

inlet

Air flow

Manometer

readings in

mm of

water

Water

flow

rate

in

lpm

―F1‖

In

Kgs

―F2‖

In

Kgs

In

Ml

Time

in

Secs.

Inlet

T2°C

Outlet

T3°C

Inlet

T1°C

Outlet

T2°C

Inlet

T4°C

Outlet

T5°C T6°C

1 2(a) 2(b) 3(a) 3(b) 4(a) 4(b) 5(a) 5(b) 6(a) 6(b) 7 8 9

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CALCULATIONS:

1.FUEL CONSUMPTION IN Kg/Hr

WF = dingsoftablereabColumn

dingsoftablereaaColumn

)3(

)3( x 3.06

2. ENGINE OUT PUT” BHP”:

BP= 4500

)( 2 21 rFFN KW

Where, N- Speed of engine in RPM

r—Radius of brake drum in mts =0.185 mt

F1&F2- Force indicated on spring balance in KGs

3.SPECIFIC FUEL CONSUMPTION (SFC):

SFC = BHP

WF Kg/BHP. Hr

4. FUEL HP(THERMAL HORSE POWER),

FHP= 4500 X 60

J x C x W VF

Where, Cv = Calorific value of diesel= 10000 K.Cal /Kg

J= Mechanical equivalent of heat=427 kg.m / K.Cal

5. PERCENTAGE THERMAL EFFICIENCY.

% η th = FHP

BHP x 100

6. AIR CONSUMPTION IN Kg/ Hr ‘Wa’

Wa = 0.6 x A0 x Va x 1.29 x 60 x 60

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Where, Ao = Area of the orifice in m2

= 4

d2

Where d= Dia.of the orifice in m = 0.015 mt

Va = 1]-)[( x 1000)(h 2g awm/

Where g = 9.81 m/ sce2

hm = Manometer reading in mm (column 5)

ρw = Density of water = 1000 Kg/ m3

ρa = Density of air = 1.29 Kg/ m

3

7.AIR TO FUEL CONSUMPTION RATIO.

Air to fuel consumption ratio = F

a

W

W

8.. TABLE OF CALCULATIONS.

Sl.NO

Engine

RPM

―N‖

Fuel

Consumed

―Wf‖

In Kg/Hr

Air

Consumed

―Wa‖

In Kg/Hr

Air to Fuel

Ratio

―Wa / Wf‖

Engine

output

―BHP‖

Specific fuel

consumption

―SFC‖

Fuel HP

―FHP‖

Brake % η

thermal

efficiency

1

2

3

4

5

6

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9. HEAT BALANCE SHHET ON MINUTE BASIS:

1. Heat supplied in fuel = Fuel consumed in Kg/min x Cv

=60

10000x W F K.Cal / min-------------------I

2. Heat carried away by engine head cooling water

= mw x Cw x (T1-T2) K.Cal / min------------------------II

3. Heat carried away by calorie meter water

= mw x Cw x (T3-T2) K.Cal / min------------------------III

4. Heat carried away by the exhaust gasses

=mg x Cp x [T5-T4] K.Cal / min------------------------IV

mg = Mass of gas = Wa + WF

5.Radiation & un Accounted = I-[ BHP+ II + III+IV] K.Cal/min—V

RESULT:

Heat balance sheet is as follows

CREDIT Kilo

Calories % DEBIT

Kilo

Calories %

Heat

supplied in

fuel

100

1.Brake power

BHP

I

BHPx 100

2.Engine head water

II

I

IIx 100

3.Calorie meter water

III

I

IIIx 100

4.Exhaust gasses

IV

I

IVx 100

5.Radiation and unaccounted

( by difference) V I

Vx 100

100 100

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ECONAMICAL SPPED TEST (4-STROKE DIESEL ENGINE)

AIM:

To conduct economical speed test on 4-Stroke diesel engine(Single cylinder)

THEORY:

The Test Ring consists of Four-Stroke Diesel Engine, to be tested for

performance, is connected to Rope Brake Drum with Spring Balance (Mechanical

Dynamometer) with Exhaust Gas Calorimeter. The arrangement is made for the

following measurements of the Set-up :

1) The Rate of Fuel Consumption is measured by using the pipette reading against

the known time.

2) Air Flow is measured by Manometer connected to Air Box.

3) The different mechanical loading is achieved by operating the spring balance of

dynamometer in steps.

4) The different mechanical energy is measured by spring balance and radius of

brake drum.

5) The Engine Speed (RPM) is measured by electronic digital RPM Counter.

6) Temperature at different points is measured by electronic digital Temperature

Indicator.

7) Water Flow Rate through the engine & calorimeter is measured by Water meter.

The whole instrumentation is mounted on a self – contained unit ready for table

operation.

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PROCEDURE:

1. Check the diesel in the diesel tank.

2. Allow diesel, start the engine by using hand cranking.

3. The engine is set to the speed of 1500 RPM.

4. Apply load from the spring balance of dynamometer.

5. Allow some time so that the speed stabilizes.

6. Now take down spring balance readings.

7. Put tank valve in to pipette position and note down the time taken for

particular quantity of fuel consumed by the engine.

8. Note down the temperature readings at different points.

9. Note down the water readings.

10. Repeat the procedure (4)&(7) for different loads.

11. Tabulate the readings as shown in the enclosed list.

12. After the experiment is over ,keep the diesel control valve at mains position.

OBSERVATIONS:

Engine

Speed

in

RPM

Spring balance

Readings Fuel pipette readings

Air flow Manometer readings

in mm of water

―F1‖

In Kgs

―F2‖

In Kgs In ml Time in Secs. H1 H2

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CALCULATIONS

1.FUEL CONSUMPTION IN Kg/Hr

WF = dingsoftablereabColumn

dingsoftablereaaColumn

)3(

)3( x 3.06

2. ENGINE OUT PUT” BHP”:

BP= 4500

)( 2 21 rFFN KW

Where, N- Speed of engine in RPM

r—Radius of brake drum in mts =0.185 mt

F1&F2- Force indicated on spring balance in KGs

3.SPECIFIC FUEL CONSUMPTION (SFC):

SFC = BHP

WF Kg/BHP. hr

4. FUEL HP(THERMAL HORSE POWER),

FHP= 4500 X 60

J x C x W VF

Where, Cv = Calorific value of diesel= 10000 K.Cal /Kg

J= Mechanical equivalent of heat=427 kg.m / K.Cal

5. PERCENTAGE THERMAL EFFICIENCY.

% η th = FHP

BHP x 100

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6. AIR CONSUMPTION IN Kg/ Hr ‘Wa’

Wa = 0.6 x A0 x Va x 1.29 x 60 x 60

Where, Ao = Area of the orifice in m2

= 4

d2

Where d= Dia.of the orifice in m = 0.015 mt

Va = 1]-)[( x 1000)(h 2g awm/

Where g = 9.81 m/ sce2

hm = Manometer reading in mm (column 5)

ρw = Density of water = 1000 Kg/ m3

ρa = Density of air = 1.29 Kg/ m

3

7. AIR TO FUEL CONSUMPTION RATIO.

Air to fuel consumption ratio = F

a

W

W

RESULT;

Economical speed test on 4-Stroke diesel engine(Single cylinder) is conducted. From

the graph economical speed of engine is---------------RPM @---------HP

Sl.NO

Engine

RPM

―N‖

Fuel

Consumed

―Wf‖

In Kg/Hr

Air

Consumed

―Wa‖

In Kg/Hr

Air to Fuel

Ratio

―Wa / Wf‖

Engine

output

―BHP‖

Specific fuel

consumption

―SFC‖

Fuel HP

―FHP‖

Brake % η

thermal

efficiency

1

2

3

4

5

6

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PERFORMANCE TEST ON RECIPROCATING AIR COMPRESSOR

AIM:

To study the working of double stage air compressor and determination of volumetric

efficiency, mechanical efficiency.

THEORY:

When the motor is started, air is sucked from the atmosphere through the

inlet air filter and orifice meter and compressed in the LP Cylinder. The hot and

compressed air is colled in the intercooler and again compressed in the HP

Cylinder.Finnally, high pressure air passes into air receiver tank through after coller and

non-return valve.

The compressor motor unit consists of a AC motor. The AC motor body

frame is mounted on trunnion bearing which swivels on application of load/torque on the

motor. The torque/load developed is measured at the torque arm of 0.2m using a spring

balance. The encoders (speed pick-ups) are provided for both motor and compressor

shafts for measurement of RPM. A toggle switch and digital RPM indicator are provided

in the control panel

The control console consists of digital speed indicator, temperature

indicator, double column manometer for air flow measurement, pressure gauges for

pressure rise measurement after each stage separately,energy meter to measure electrical

input to the motor. The neccssary mains ‗ON‘ indicators and switches are provided for

completeness of the instrumentation.

The complete unit is built-in. Foundation is not neccssary for installation

of the test rig. The pressure tappings and temperature sensors after each stage are

connected to pressure gauges and indicators in the control panel. Air volume measuring

chamber with orifice of 15mm diameter is fixed beneath the control console and tappings

connected to double column manometer for air intake measurements.

PROCEDURE;

1. Release the pressure of air fully from tank, if previously pressurized.

2. Check zero level in the double column.

3. Switch –ON the mains and observe the light indicators ON.

4. Keep the outlet valve closed.

5. Switch-ON the starter and allow motor to run full speed.

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6. As the pressure in the receiver tank increases , set the pressure by obtaining the

delivery valve to 1,2,3 Kg/ cm2

as observed from the pressure gauge and note the

readings.

7. Note down the flow rate manometer readings at different pressures.

8. Note down pressure after LP cylinder, after HP cylinder, temperatures after LP

cylinder, after inter cooler , after HP cylinder and at the inlet.

9. Note down the energy meter reading, speed and air temperature.

10. Tabulate the above readings as shown.

11. Stop the compressor and release the pressure from the tank after the experiment is

completed.

OBSERVATIONS:

T1= Air inlet temperature

T2= After first stage

T3=After inter cooler

T4=After second Stage

E.M Constant=150 Rev/ KWH

Orifice Dia=15mm

Torque arm=0.2m

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Sl.

No

P1(LP)

Pressure

after first

stage in

Kg/ cm2

P2(HP)

Pressure

after

second

stage in

Kg/ cm2

Energy

meter

reading

No.of

revns./

Time

in

Secs.

Air flow

across

Orifice in

mm of

water

hw

RPM of

compre

ssor

RPM

of

motor

Swinging field

Spring balance

readings inKg

Temperature

Points

T1 T2 T3 T4

1

2

3

4

5

CALCULATIONS:

1. Density of Air at 30° C (δa) = 1.293 Kg/ m3

2. Water Density (δw) = 1000 Kg/ m3

3. Acceleration due to gravity,g = 9.81 m/sec2

4. Orifice diameter = 15 mm

5. Co-efficient of discharge of orifice, Cd= 0.64

6. Torque arm distance = 0.2m

7. INPUT TO COMPRESSOR =Energy meter reading

=150

5 x

736

60 x 60 x

t

1000 hp

( where ‗t‘ is time in Secs.for 5 revns)

8. COMPRESSOR OUTPUT = 736

H Q Wa

Where, Wa = 1.293 Kg/ m3

= 12.68 N/ m3

H(Head in meters of water) = Wa

P x 10

4

‗P‘ is read on after HP cylinder pressure in Kg/ cm2

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‗Q‘(Flow rate) = Cd A aH g 2 m3/ sec

‗A‘ (Area of orifice) = 4

x d2

= 1.766 x 10 -4

m2

Ha = 1000

hw1

a

w = 0.772 hw

Q = 0.62 x1.766 x 10 -4

m2 x wh 0.772 x 9.81 x 2

Q = 4.2612x10 -4

x wh

Where hw = Head measured in mm of water across orifice plate.

9. % EFFICIENCY OF COMPRESSOR (MECHANICAL)

% η compressor = input Electrical

output Compressor x 100

10. SWEPT VOLUME OF PISTON (LP) = Area of Piston x Stroke

Vs1= 4

x (0.07)2 x 0.085 = 3.2711 x 10

-4 m

3

11. SWEPT VOLUME OF PISTON (LP) = Area of Piston x Stroke

Vs2= 4

x (0.05)2 x 0.085 = 1.6689 x 10

-4 m

3

Vs = Vs1+ Vs2

12. ACTUAL AIR SWEPT

Va = compressor of RPM

60 x Q m

3

13.VOLUMETRIC EFFICIENCY

% η V = s

a

V

V x 100

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Sl.No Electrical

Input in

HP

Discharge

Q

In m3/sec

―H‖

In mts

of air

Compressor

Output in

HP

Theoretical

swept

volume

Actual

swept

volume

%

efficiency (Mechanical)

%

volumetric

efficiency

1

2

3

4

5

RESULT:

Volumetric efficiency, mechanical efficiency of double stage air compressor is

calculated.

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PORT TIMING DIAGRAM OF A 2-STROKE PETROL ENGINE

AIM:

To draw the port timing diagram of a 2-stroke petrol engine by studying given out

section model

THEORY:

Port timing diagram is a graphical representation of exact model is the

sequence of operations at which inlet exhaust and transfer port open and closes as well as

firing of fuel. It is generally exposed in terms of angular position of crank shaft.

In theoretical port timing diagram of 2-stroke petrol engine. The fuel is

fired at A i.e., spark advances takes places from TDC to BDC at B both inlet & exhaust

ports are open and motion as well as exhaust port are takes place from B to C position

moves first to BDC and then slightly upwards to ‗C‘. Both the plate‘s parts are closed and

compression takes place from C to A. The crank shaft revolves through 1200

appproximately and piston moves to TDC in 2-stroke engine crank revolves through 3600

In actual port timing diagram the expansion of the change starts as

position of piston moves from TDC towards BDC first of all burnt gases leaving the

cylinders after a small revolution of crank revolution. The transfer port also opens and

fresh fuel air mixture center into engine cylinder now piston reaches BDC and then starts

moving up wards. As crank moves a little and BDC. The first transfer port closes and

then exhaust port closes. Now the change is compressed with both parts closed & then

ignited with help of spark plug before the end of compression stroke. This is done as the

change required same time to ignite by the time position reaches to TDC. The burnt

gasses push the position downwards with fire and the expansion of burnt gasses takes

place opens and close at equal angle on either side of BDC position.

TPC: Transfer port closed 640 after BDC

EPC: Exhaust port closed 830

after BDC

EPO: Exhaust port opens 680

before BDC

TPO: Transfer port opens 480 before BDC

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PROCEDURE:

1. First observe the various parts of a 2-stroke petrol engine at given section model

2. Now set up the pointer which placed on the flywheel to 00 and position at BDC

3. Slowly move the flywheel after some time before reaching TDC. Then inlet port

opens measure of angle at which pointer shows

4. The inlet port opens at 300 before TDC. now position reaches TDC and BDC the

inlet valve closes 700

before BDC

5. The spark advance takes places 450

before TDC the exhaust port closes at800

after BDC and transfer port closes at 600 after BDC

6. Now position moves from TDC towards BDC suction and compression starts in

previous stroke which the piston reaches BDC. And again inlet port closer at 700

before BDC

7. Transfer port is closed at 600

after BDC and and exhaust port closes at 800

after

BDC

RESULT:

1. Scavenging suction process covered =

2. Compression process covered=

3. Expansion process covered=

4. Exhaust process covered=

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VALVE TIMING DIAGRAM OF 4-STROKE DISEL ENGINE

AIM:

To draw the valve timing diagram of 4-stroke engine by studying the cut section

model

THEORY:

1. The Theoretical valve timing diagram for 4-stroke diesel engine is shown in

figure. In this the diagram inlet valve opens at A.

2. The solution takes place from A to B. The crank shaft revolves through 1800 &

the piston moves from TDC to BDC.

3. It B the inlet valve closes and the compression revolves through 1800

and the

piston moves from BD to TDC.

4. A ‗C‘ the fuel injection takes places i.e. injection valve opens and fuel is fixed by

the compression

IVO: Inlet Valve open

IVC: Inlet valve close

FVO: Fuel valve open

FVC: Fuel valve close

EVO: Exhaust valve open

EVC: Exhaust valve close

PROCEDURE:

1. Observe the various parts of4-stroke diesel engine and various strokes of engine.

After this set the pointer at flywheel at zero

2. Now position at BDC on moving slowly the flywheel inlet valve opens before the

position reaching to TDC. Reading are noted

3. Inlet valve opens before TDC and after slowly moved flywheel in the same

direction. The position reaches TDC and then BDC

4. After BDC the inlet valve closes note the position of the inlet valve closes 130

after BDC

5. Slowly move the flywheel in same direction after closing of inlet valve suction

stroke is completed

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6. Exhaust valve is opens at 350 before BDC exhaust valve closes 8

0 after TDC.

Same time exhaust stroke completes and cycle is completed

PRECAUTIONS:

1. Readings should be taking without parallax error

2. Observe carefully the valves are closed or in open

RESULT:

The valve timing diagram of 4-stroke diesel engine is studied with the help of given

cut section model

1. Suction covered =

2. Compression covered =

3. Expansion covered =

4. Exhaust covered =

5. Overlap =

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DIS-ASSEMBLY AND ASSEMBLY OF A ENGINE.

AIM:

To study the procedure for dis-assembly and assembly of a specific engine by

making a practical trail on it.

THEORY: The main parts of any engine are,

Cylinder Block:

1. It forms the basic frame work of the engine.

2. It houses the engine cylinders.

3. Serves as bearing or support and guides the piston reciprocating in it.

4. Block contains passengers for circulation of cooling water and lubricating oil.

There are two types of rings

a) Compression ring

b) Oil control ring

Connecting rod:

It connects the piston with the crank shaft thus facilitative the transmission

of power combustion chamber to the crank shaft it also converts the reciprocating motion

of the piston into rotary motion of crank shaft.

Fly wheel:

The fly wheel absorbs the energy power source and gives out this energy the other

3-strokes keeping the crank shaft rotating at uniform speed through out.

Cam shaft :

A shaft is responsible for opening the valves on addition the crank shaft operates.

Cylinder head:

1. The head is a mano block casting.

2. It contains spark plug notes and cooling water Sackets, valve opening

mechanism is mounted.

3. Complete valve opening mechanism is mounted on the head.

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Piston:

The top of the piston is called head or crown it may be either done are may

specially to form a desired shape of combustion chamber jointly with the cylinder block.

Piston pin:

It provides a seal b/w the piston fuel pump. Oil pump and distributor valves.

Valves:

These are accurate by the cams which in turn are operated by crank shaft and

perform following functions.

PROCEDURE FOR ENGINE DIS-ASSEMBLY.

For dis-assembly the engine,it should be mounted in a suitable stand.Engine dis-

assembly is carried out in a sequence as follows and engine is out of the vehicle and all

the accessories have been removed and oil has been drained.

Remove water pump.

Remove exhaust manifold

Remove oil filter

Remove water outlet fitting

Remove thermostat

Remove crank shaft pulley

Remove oil pump

Remove crank case ventilation valve

Remove rocker arm assembly

Remove cylinder head.

Remove oil pan.

Remove piston rod and connecting rod.

Remove timing gear cover.

Remove front end plate.

Remove fly wheel housing.

Remove fly wheel, clutch

Remove crank shaft.

Remove exhaust valve and springs.

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Remove cam shaft, valve tappers.

Remove oil gallery plugs.

PROCEDURE FOR ENGINE DIS-ASSEMBLY.

First clean the cylinder block with fresh oils. Piston is connected to connecting

rod with gudge pin .This piston have the piston rings.

After fixing the rings piston is inserted in to the cylinder block with help of ring

compressor.

These rings are fitted in the piston grooves with help of calipers.

The crank shaft has been placed on the bottom of the cylinder block the

connecting rod is connected to its crank.

The fly wheel is attached to the crank shaft one side.

On the other side of the crank shaft timing gear is fitted. It is for valve operating.

This equipment is placed on the sump of the engine.

After fixing on the sump the cam shafts are fitted in the cylinder head in the inlet

valve & exhaust valves are fitted with help of G-clamp

To this cylinder the intake manifold and injectors are fitted one side.

Other side of the cylinder head the exhaust manifold is fitted.

Fill the sump with new oil.

After fill up the oil the water pump is fitted.

The thermostat is also fitted to this engine then the re assembly of the given

engine is completed.

RESULT:

Thus the procedure of the assembling of a engine is studied and recorded.

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