PROJECT REPORT ON
MAINTENANCE OF DIESEL AND PETROL ENGINE
MAINTENANCE OF DIESEL AND PETROL ENGINE
SUBMITTED IN THE PARTIAL FULFILLMENT OF THE REQUIREMENT
FOR THE AWARD OF DIPLOMA
IN
MECHANICAL ENGINEERING
FROM
GOVERNMENT POLYTECHNIC KANGRA
FOR THE AWARD OF DIPLOMA
IN
MECHANICAL ENGINEERING
FROM
GOVERNMENT POLYTECHNIC KANGRA
UNDER THE
SUPERVISION OF
ER. D.R. SHARMA
(H.O.D MECHANICAL ENGINEERING)
SUBMITTED BY
ER. D.R. SHARMA
(H.O.D MECHANICAL ENGINEERING)
SUBMITTED BY
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S.No.
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Name
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S. No.
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Name
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1.
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Pankaj
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7.
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Rohit
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2.
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Punnet
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8.
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Sajan
Lakhanpal
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3.
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Rajat Dhiman
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9.
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Santosh
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4.
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Rajnesh
Kumar
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10.
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Shantanu
Rana
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5.
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Reshav
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11.
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Shubham
Awasthi
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6.
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Robin
Bhardwaj
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12.
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Shubham
Chaudhary
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GOVT. POLYTECHNIC KANGRA
(AS ISO 9001 : 2008 CERTIFIED INSTITUTE)
(AS ISO 9001 : 2008 CERTIFIED INSTITUTE)
DEPARTMENT
OF MECHANICAL ENGINEERING
CERTIFICATE
Certified
that the project entitled “MAINTENANCE
OF DIESEL AND PETROL ENGINE” submitted by Pankaj Dheer, Punnet, Rajat
Dhiman, Rajneesh Kumar, Reshav, Robin Bhardwaj, Rohit, Sajan Lakhanpal, Santosh
Kumar, Shantanu Rana, Shubham Awasthi, Shubham Chaudhary in the partial
fulfilment of the requirement for the award of DIPLOMA in MECHANICAL
ENGINEERING of HIMACHAL PRADESH
TAKNIKI SHIKSHA BOARD DARI, DHARAMSHALA is record of student’s practice
work carried out under our supervision and guidance. It is further understood
that by this certificate the undersigned do not endorse or approve any
statement made, opinion expressed or conclusion drawn there in but approve the
report only for the purpose for which it is submitted.
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Supervisor
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Head of Department
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Er. D.R. Sharma
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Er. D.R. Sharma
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Er. Parul Dhiman
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ACKNOWLEDGEMENT
No volumes of words are enough to
express our gratitude toward our guides Er. PARUL DHIMAN, LECTURER in Department of Mechanical Engineering,
Government Polytechnic Kangra who have been very concerned and have guided for
all the ideas and solved our quires in the preparation of this project. They
have been very co – operative and sincere to guide us through to see our hard
works become fruitful.
We
are thankful to ER. D.R. SHARMA, Head of
Department, Mechanical Engineering, Government Polytechnic, Kangra and also
our project coordinator, for giving us the opportunity to carry out this
project.
Most
importantly we would like to thank almighty for showing use the right path, to
help us stay calm in the oddest of the time and keep moving even the times when
there was no hope.
Lastly
we thank our friends and persons who were involved directly or indirectly and
spared time to cite valuable suggestions without which this work would not have
casted in to present form.
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TABLE OF CONTENTS
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S.NO.
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DESCRIPTION
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PAGE NO.
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1.
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Certificate
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2
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2.
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Acknowledge
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3
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3.
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Introduction (Diesel Engine)
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5
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4.
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Objective And Aim
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7
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5.
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Specification of Diesel Engine
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8
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6.
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Various Parts of Diesel Engine
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9
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7.
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Dismantling Procedure (Diesel Engine)
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14
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8.
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Common fault and solution of Diesel Engine
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15
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9.
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How to Diagnose Fuel Injector Problem
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18
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10.
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Maintenance of Petrol Engine
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23
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11.
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Technical Specification (Petrol Engine)
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24
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12.
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Tool and Equipment Used
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25
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13.
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Dismantling Procedure (Petrol
Engine)
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26
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14.
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Main Parts (Petrol Engine)
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27
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15.
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Common Faults (Petrol Engine)
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29
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16.
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How to Diagnose Carburetor Problem
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30
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17.
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Symptoms of bad or failing spark plug
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33
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18.
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Symptoms of bad or failing distributor rotar and cap
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36
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19.
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Proper Firing order of a 4 Cylinder Petrol Engine
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38
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20.
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Cost Estimation
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39
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21.
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Conclusion
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41
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22.
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Reference
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42
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INTRODUCTION (DIESEL
ENGINE)
The diesel engine (also known as a compression-ignition or CI
engine) is an internal
combustion engine in which ignition of the fuel that has been injected into the combustion chamber is caused by the high temperature which a gas achieves
(i.e. the air) when greatly compressed (adiabatic compression). Diesel engines work by compressing only the air. This
increases the air temperature inside the cylinder to such a high degree that it ignites atomized diesel
fuel that is injected into the combustion chamber. This contrasts with
spark-ignition engines such as a petrol
engine (gasoline engine)
or gas engine (using a gaseous fuel as opposed to petrol),
which use a spark plug to ignite an air-fuel mixture. In diesel engines, glow plugs (combustion chamber pre-warmers) may be used to aid
starting in cold weather, or when the engine uses a lower compression-ratio, or
both. The original diesel engine operates on the "constant pressure"
cycle of gradual combustion and produces no audible knock.
The diesel engine has the highest thermal efficiency (engine efficiency) of
any practical internal or external
combustion engine due to its very high expansion ratio and inherent lean burn which enables heat dissipation by the excess air. A
small efficiency loss is also avoided compared to two-stroke
non-direct-injection gasoline engines since unburned fuel is not present at
valve overlap and therefore no fuel goes directly from the intake/injection to
the exhaust. Low-speed diesel engines (as used in ships and other applications
where overall engine weight is relatively unimportant) can have a thermal
efficiency that exceeds 50%.
Diesel engines may be designed as
either two-stroke or four-stroke cycles. They were originally used as a more efficient
replacement for stationary steam
engines. Since the 1910s they have been used in submarines and ships. Use in locomotives, trucks, heavy equipment and electricity generation plants followed later. In the
1930s, they slowly began to be used in a few automobiles. Since the 1970s, the use of diesel engines in larger
on-road and off-road
vehicles in the US increased. According to the British Society of
Motor Manufacturing and Traders, the EU average for diesel cars accounts for 50% of the total
sold, including 70% in France and 38% in the UK.
The world's largest Diesel engine
put in service in 2006 is currently a Wärtsilä-Sulzer
RTA96-C Common Rail marine diesel, which produces a peak power
output of 84.42 MW (113,210 hp) at 102 rpm.
OBJECTIVE AND AIM
OBJECTIVE:
To learn the proper technique of
dismantling a single cylinder diesel engine to study the function, material and
serviceability of each part. Reassembly of serviceable parts for proper
function of the engine.
GENERAL
AIM:
Ø develop
logical processes of faultfinding
Ø learn
the correct use and care of the tools and equipment associated with this module
Ø be
familiar with the function of the various components associated with diesel
engines
Ø develop
safe working practices and be aware of the hazards of their workplace or
location
Ø perform
a range of maintenance procedures associated with diesel engines
SPECIFICATIONS OF DIESEL ENGINE
Technical Specifications for
high speed air cooled Single cylinder diesel Engine (OMA -2)
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Rating
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4 – 8 KW/6.5 HP)
|
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Governing
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Class
– BI
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Fuel
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H.S.
DIESEL
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Type
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OMA
– 2
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R.P.M
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1500
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SFC.
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252g./kwh.
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LUB. Oil
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SAE
30/40
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Manufacture
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OPEX
Engineering Corporation – Pahgwara
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VARIOUS PARTS OF DIESEL ENGINE (OMA -2)
Ø CYLINDER BLOCK: Cylinder block or Cylinder are main part of an engine. It is
a part in which combustion of fuel takes place. All other parts like piston,
connecting rod, crankshaft, water jacket etc. are bolted on it.
Ø PISTON:
Piston is placed in the cylinder and transmits thrust to the connecting rod. It
is free to move. It compresses the air fuel mixture and convert the fuel energy
into mechanical energy. It transmits the power to the crankshaft.
Ø CYLINDER HEAD: Cylinder
head is fitted on the top of cylinder block and the function of the cylinder
head is to seal the working end of cylinder and not to permit entry and exit of
gases on cover head valves of the engine. The valves, spark plug, camshaft etc.
are fitted on it.
Ø CONNECTING RODS: It
connect piston to the crank shaft and transmit the motion and thrust of piston
to crank shaft. The lower end of connecting rod is connected to the piston and
the bigger is connected to the crank shaft.
Ø CRANKSHAFT: It is located in the bottom end of cylinder block. It
transmits the reciprocating motion of piston into rotary motion. This rotary
motion used to rotate wheels of the vehicle.
Ø CAM SHAFT: It is fitted either in the cylinder head or at the bottom of
the cylinder block. It is use to open or close valves at proper timing in
multi-cylinder engine.
Ø VALVES: It is fitted on the cylinder head. It regulates the flow of
air fuel mixture inside the cylinder and exhaust gas outside the cylinder block.
When
both inlet and exhaust valves are closed no pressure can go inside or outside
of cylinder block.
Ø INJECTOR: It is
used in Diesel engine (Compression Ignition Engine). It is fitted on the
cylinder head. It is used to inject fuel in spray form inside the cylinder at
the end of compression stroke.
Ø PUSH ROD: It is used when the camshaft is situated in the bottom of the
cylinder head.
It regulates the timing of valves open and
close through rocker arm and camshaft.
Ø MANIFOLD: It is bolted on the cylinder head one each for intake and
exhaust. Its function is to evenly distribute air-fuel mixture for intake &
collects the exhaust gases from all cylinders.
Ø PISTON RINGS: It provides the good sealing fit and less friction resistance
between piston and cylinder. It is split at one point so it can be easily
installed into the grooves cut in the piston.
Ø ENGINE BEARING: Bearings are used to support
the moving parts. The purpose of bearings is to reduce friction. The crankshaft
is supported by bearing. In engine two types of bearing are used sliding
bearing and rolling bearing.
DISMANTLING PROCEDURE:
Ø Drain oil from the sump.
Ø Remove the rocker box and rocker
assembly.
Ø Remove the push rods.
Ø Remove the air cleaner and silencer
along with elbow pipes from the cylinder head. Disconnect the high pressure
line to the injector and take out injector.
Ø Remove the inlet valve, exhaust
valve, valve springs and valve cotters.
Ø Remove the side cover and loosen the
big end of the connecting rod and take out the piston along with connecting
rod.
Ø Use ring expander to remove the oil
and compression rings.
Ø Remove the circlips from the piston
using circlip plier. Push out the gudgeon pin and separate the connecting rod
from the piston.
Ø Remove the cylinder block.
Ø Remove the timing cover and take out
camshaft and crankshaft gears.
Ø Remove the fuel injection pump.
Ø Remove the side cover of the fuel
injection pump.
Ø While removing the cam shaft, make
sure that tappet rollers for inlet valve, exhaust valve and fuel injection pump
do not fall in the sump.
Ø Remove the fly wheel with puller.
Ø Remove the front and rear covers
housing ball bearing for the journals.
Ø Remove the oil filter and plunger
type oil pump and take out the crank shaft from the crank case. Thus the engine
parts are almost dismantled. Clean all the parts for review to replace or
service for assembly.
Common Faults and Solutions of Diesel
Engine
DIESEL ENGINE CANNOT START SEVERAL REASONS
Prerequisite for normal diesel engine operation
is atomized diesel accurate and timely sprayed into the combustion chamber and
the combustion chamber of compressed air to reach a sufficient temperature in
order to fire outbreak. To meet
these two conditions, it must have a high enough speed and a certain
temperature within the cylinder diesel engine starting. Diesel engine cannot start from the
start of work, look for the causes of diesel engine fuel supply system and
compression.
· The ambient temperature is
too low. In the case of low
temperatures, the engine warm-up should be prepared, otherwise difficult to
start.
· Starting speed. Hand start diesel engine, you should
gradually increase the speed, and then pull the decompression lever to the
non-decompression position, so that normal compression cylinder. If the decompression agency improperly
adjusted or valve withstood piston, tend to feel the shaking car is very
laborious. Which is characterized
by the crankshaft to go to a site on the turn no more, but it can be returned
to. At this point, in addition to
check the decompression institutions should also check the timing gear meshing
relationship wrong.
EXHAUST
BLACK SMOKE FOR THE FOLLOWING REASONS:
·
Uneven pressure fuel supply to the excessive or cylinder fuel
supply
·
Valve sealing leakage, resulting in leakage, low cylinder
compression pressure
·
Air filter inlet obstruction, resistance of the inlet into
the gas
·
Cylinder, piston, piston rings severe wear
·
Injector bad work
·
Engine overload
·
The fuel injection pump fuel delivery advance angle is too
small, the combustion process to the exhaust process
·
Gasoline fuel injection system control failure
The black smoke of the
engine through the high pressure oil pump adjustment, fuel injector spray test
to check the cylinder compression pressure measurement, inlet cleaning, fuel
supply advance angle adjustment, gasoline fuel injection system failure
diagnostic work to be inspected and excluded.
KNOCKING SOUND
Knock, refers to a piston
working stroke of the moment, or piston row, issued by the piston in the
cylinder of the swing, the head and skirt and cylinder wall collision
"Dangdang" or "blah" abnormal
sound. "Blah" sound,
the exhaust pipe to take the blue smoke, generally due to the piston and
cylinder wall clearance is too big reason. The
main reason for these are the following:
·
If only after the cold start of this
phenomenon. Running up to the
normal water temperature when away on its own, because the piston and cylinder
wall with the gap is too large, cold car piston another contraction, both with
the gap is further increased, thereby percussion. Machine temperature rise after the
piston expansion, the gap tends to normal, it is abnormal sound disappeared. This case no major problems in the
short term.
·
Oil grade and requirements does not
match the engine flameout a long time, started again, the oil viscosity, poor
liquidity, the short period of time the cylinder wall cannot form a good film,
piston and cylinder wall, directly resulting from collisions knock. In operation for some time, the
lubricating oil viscosity is normal, the formation of a layer of film on the
cylinder wall, abnormal sound is diminished or disappeared. Reasonable selection of lubricants, to
warm up before starting the engine crankcase, mixed with oil lubrication,
before the start of multi-step a few times to start the rod, so that mechanical
adhesion more lubricants, such a situation that is, can be avoided.
·
Gas mixture in the cylinder cannot be
normal combustion, resulting in the moment of early burning or deflagration, or
engine no load fierce fuel door, will produce the sound of crashing by the
piston and cylinder wall. Should
keep the engine at normal temperature, to meet the octane requirements for
gasoline, and appropriate adjustments to ignition timing.
·
the piston skirt wear, cylindricity
error is too large, the piston line, the top will hit the cylinder walls,
pistons and cylinder serious wear and tear, the gap between the two?? Wall. The biodegradable check, under the
circumstances to take the appropriate repair measures.
·
due to rod bending and torsion, piston
pin and the pin hole deflection, crank pins and piston pin two axis lines not
parallel, will cause the piston in the cylinder skew run and hit the cylinder
wall. This situation can only
decompose to check and replace the corresponding parts in the diagnosis.
HOW TO DIAGNOSE FUEL INJECTOR PROBLEMS
Fuel injection is the introduction
of fuel in an internal combustion engine, most commonly automotive engines, by
the means of an injector.
All diesel
engines use fuel injection by design. Petrol engines can use gasoline direct
injection, where the fuel is directly delivered into the combustion chamber, or
indirect injection where the fuel is mixed with air before the intake stroke.
UNDERSTAND FUEL INJECTORS
Before setting to work diagnosing
fuel injector problems, it helps to understand what fuel injectors are. This
section describes the basic process of how a fuel injection system works and
the role that fuel injectors play in this process.
FUEL INJECTION SYSTEM BASICS
A car's engine uses an internal
combustion process to generate power, with the two key ingredients to this
process being oxygen and fuel. The engine takes oxygen from the air surrounding
it and fuel from the reservoir that holds the car's gasoline. An air intake
system delivers the air to the engine and a fuel injection system delivers the
gasoline. The engine's gas supply is limited, so in order to use it efficiently
the engine must apply the right amount of gasoline to mix with the oxygen that
it is receiving. Since the oxygen supply fluctuates, the fuel injection system
must constantly change the amount of gasoline that it delivers, and it must
deliver the gasoline in a precise manner so as not to waste any of it.
THE
ROLE OF FUEL INJECTORS
Fuel injectors play a very
important role in the engine's fuel delivery system in that they deliver the
exact amount of gasoline that the engine needs, even as the requirements shift
quickly and constantly. An injector is a valve with electronic controls that
receives signals from the engine control unit. A gas pump delivers pressurized
gasoline into the fuel injectors and the engine control unit tells the fuel
injectors to open a valve to let the pressurized gas pass through an atomizing
nozzle. The fuel injectors thereby spray a fine gasoline mist into the engine's
intake manifold, which then delivers it to the engine for combustion with the
oxygen that the engine is receiving. This mist makes for more efficient burning
of the gas in combustion than if it were in droplet form. The more gasoline
that the engine requests, the longer the valves in the fuel injectors stay
open. Pulse width describes the amount of time that the valves stay open.
BECOMING
FAMILIAR WITH COMMON FUEL INJECTOR PROBLEMS AND THEIR SYMPTOMS
This section describes the problems
and symptoms that are related to fuel injector problems. It is important for
readers to be familiar with these problems and symptoms if they plan to
diagnose the fuel injectors on their own, as this will help them to accurately
diagnose problems.
COMMON
PROBLEMS
This section lists the most common problems that are associated with fuel
injectors. Some problems are easy to correct, while others require replacement
of the fuel injectors.
Dirty Fuel
Injectors
Fuel additives that do not spray into the intake manifold can leave a
residue on the fuel injectors. These can burn and form a crust because fuel
injectors run very hot due to the friction that is produced from rapid and repetitive
movement. The crust on the fuel injectors can result in a weak spray and an
uneven pattern.
Clogged Fuel
Injectors
Fuel injectors can also clog from the buildup of microscopic foreign
objects, which are usually in the form of rust. This is typically introduced
from a source upstream in the gasoline supply, such as the fuel supply line or
the fuel rail, and it can result from a car sitting idle without maintenance
for a long time. A clogged fuel injector will not be able to supply gasoline to
the intake manifold.
Fuel Injector
Does Not Open
The valve in the fuel injector might not open as the result of faulty
windings or as the result of a rusted fuel injector. The windings might
overheat, short out, or break, and rust can cause the valve to stick. In any of
these instances, the valve will not open and the fuel injector will be unable
to deliver gasoline through its nozzle.
Fuel Injector
Does Not Close
The valve in the fuel injector might also be unable to close due to a
faulty spring or due to a buildup of rust or fuel additives. If the valve is
unable to close properly, the fuel injector will leak gasoline.
Fuel Injector
Leaks
The fuel injector may also leak gasoline if other parts of the system
fail, such as the mechanism that cools the injector. The fuel injector can then
overheat and fail, resulting in a leak. It is also possible that the injector
has a faulty part that does not enable it to function properly.
Symptoms That Can Signify a Problem
The table below describes the various symptoms that can signify a
possible problem with fuel injectors. It also associates the problems detailed
above with these symptoms.
Symptom
|
Description
|
Associated Problems
|
|
Inconsistent
Engine Power
|
An
inconsistent fuel supply can cause the engine to rev high and low, with the
RPM gauge fluctuating.
|
Dirty fuel
injector
|
|
Misfiring
Engine
|
When the fuel supply is inadequate upon ignition, the engine might
misfire. An 8 to 10 percent reduction in one fuel injector can cause this to
occur.
|
Dirty fuel
injector
Clogged
fuel injector
Fuel
injector does not open
|
|
Uneven
Engine Idling
|
An engine should idle smoothly, but an uneven fuel supply will cause
idling disturbances.
|
Dirty fuel
injector
|
|
Fuel Scent
|
Leaking fuel from a faulty fuel injector will create a strong gasoline
smell.
|
Fuel
injector does not close
Fuel
injector leaks
|
|
Diminished
Gas Mileage
|
A fuel injector that delivers drops of gasoline instead of a mist will
make for inefficient use of the gas, reducing the car's gas mileage.
|
Fuel
injector does not close
Fuel
injector leaks
|
Being able to observe these symptoms is an important aspect of realizing
that there is a problem with a car, and being able to associate these symptoms
with specific fuel injector problems will help car owners to resolve the issues
with their injectors quickly.
RUN DIAGNOSTIC TESTS
This section describes a few tests that owners can run to help them to
diagnose fuel injector problems. These tests are relatively simple, though they
do require accessories to complete them.
·
Measure Exhaust Manifold Temperatures
If a fuel
injector will not close, it will dump gasoline on the catalyst that opens and
closes the valve, causing it to overheat and burn out. This will produce high
temperatures at the exhaust manifold while the engine is warm. If the valve
will not open, an excessive amount of oxygen will disable the catalyst,
producing excessively low temperatures at the exhaust manifold. To determine
whether this is an issue, point a laser
thermometer at the pipes of the
exhaust manifold while the engine is warm. A normal reading on each cylinder
will be within 30 degrees of 450 degrees Fahrenheit. An injector that will not
open will yield a temperature of 200 to 250 degrees and an injector that will
not close will show temperatures of 600 degrees or more.
·
Listen to the Fuel Injectors
Another
helpful diagnostic tool is an engine
stethoscope. This tool enables a car owner to listen for any problems with the
fuel injectors by placing the tip of the stethoscope on each injector. Fuel
injectors make a sharp clicking sound when they are functioning properly, so
the absence of this sound can indicate a problem with an injector.
·
Inspect the Fuel Injectors
A third way that car owners can
diagnose their cars' fuel injectors at home is by removing the fuel injectors
and inspecting them. Start by detaching the fuel rails to which the injectors
are likely attached. After removing the rails, detach each fuel injector from
each rail. Fuel will flow from the rails as each injector is removed, so be
sure to wear gloves during this process. After removing all of the fuel
injectors, inspect each one for signs of cracks or damage to any of the parts
within the injectors.
MAINTENANCE OF PETROL ENGINE
A petrol engine (known as a gasoline engine in American English) is an internal combustion
engine with spark-ignition, designed to run on
petrol (gasoline) and similar volatile fuels.
In most petrol engines,
the fuel and air are usually pre-mixed before compression (although some modern
petrol engines now use cylinder-direct petrol injection). The pre-mixing was
formerly done in a carburetor, but now it is done by electronically controlled fuel injection, except in small engines where the cost/complication of
electronics does not justify the added engine efficiency. The process differs
from a diesel engine in the method of mixing
the fuel and air, and in using spark plugs to initiate the
combustion process. In a diesel engine, only air is compressed (and therefore
heated), and the fuel is injected into very hot air at the end of the
compression stroke, and self-ignites.
TECHNICAL SPECIFICATIONS
|
TYPE
|
4 CYLINDER, VERTICAL,
INLINE
|
|
BORE X STROKE IN MM
|
78 X
17.5
|
|
TOTAL DISPLACEMENT
|
1366 CC
|
|
MAX POWER (GROSS)
|
43.4@ 4600 RPM
(AS PER SAE-J-1391) |
|
MAX TORQUE (GROSS)
|
7 KG.MK. @ 2800 RPM
(AS PER SAE – J – 1391) |
TOOLS AND EQUIPMENT:
·
A kit of tools consisting socket
·
Spanner Set
·
Ring Spanners
·
Double ended spanners
·
Spark Plug Spanners
·
Feller Gauge
·
Combination Plier
·
Nose Plier
·
Circlip plier
·
Piston ring clamp
·
Bearing puller
·
Screw Driver
·
Mallet
·
Steel Tray
·
Brush
·
Diesel Oil
·
Cotton waster
·
Clean rags
·
Lubricating oil
·
Grease etc.
DISMANTLING PROCEDURE:
·
Drain oil from the gear box.
·
Remove the carburetor and put it in a clean tray.
·
Loosen the spark plug with the spark plug spanner and keep
it aside.
·
Remove the cylinder head and cylinder block.
·
Remove the magnet assembly with a special puller.
·
Remove the clutch assembly.
·
Remove the gear shifter.
·
Remove the crankcase bolts, to have access to the
crankshaft, connecting rod and piston.
·
Remove the circlips of the gudgeon pin and separate the
piston from the connecting rod small end.
·
Remove the compression rings using ring expander.
·
Remove the crank shaft bearing with the puller and remove
the connecting rod.
MAIN PARTS
|
S.No.
|
Name of Part
|
Function
|
Material
|
|
1.
|
Cylinder Head
|
It is a cover for closing one end of cylinder and
accommodates the spark plug.
|
Aluminum Alloy
|
|
2.
|
Cylinder
|
It acts as an enclosure for the air fuel mixture for
compression and ignition, to liberate heat form mechanical energy.
|
Aluminum Alloy
|
|
3.
|
Piston
|
It is the reciprocating part in the cylinder to
suck, compress and exhaust the charge and converts pressure energy of the
ignited charge into mechanical energy of the crankcase.
|
Aluminum Alloy
|
|
4.
|
Piston Rings
|
These prevent the leakage past the piston and
cylinder wall.
|
Cast Iron
|
|
5.
|
Gudgeon pin
|
It acts an inter link between piston and small end
of connecting rod.
|
Case Hardened steel or Alloy Steel
|
|
6.
|
Connecting Rod
|
It acts an inter link between piston and crankshaft
to transmit the mechanical energy of the piston to the crankshaft.
|
Alloy Steel
|
|
7.
|
Crankshaft
|
It converts the reciprocating motion of the piston
received by the connecting rod into rotary motion.
|
Alloy Steel
|
|
8.
|
Flywheel cum Fan
|
It provides energy to the piston to perform power
consuming operations i.e. suction, compression and exhaust.
|
Aluminum Alloy
|
|
9.
|
Main Bearings
|
These act as a support for the crankshaft between
the crankshaft and the crank case by providing needle bearing or ball
bearing.
|
Steel
|
|
10.
|
Spark Plug
|
It ignites the compressed charge of air fuel mixture
with the help of spark produced between the electrodes.
|
Central electrode enclose with porcelain insulation
and steel body.
|
|
11.
|
Ignition System
|
It consists of magnet assembly having primary coil,
secondary coil, CB Points, ignition coil and permanent magnet to produce the
high tension current to ignite the mixture of air fuel.
|
Steel magnet copper winding of coils with
aluminum condenser
|
|
12.
|
Carburetor
|
It is a device to mix air and fuel in proper ratio
and supply to the cylinder at proper time.
|
Aluminum body gun metal
|
|
13
|
Air Cleaner
|
It removes dust and dirt from the incoming air.
|
Jets Perorated paper
|
|
14.
|
Gear Box
|
It consists of clutch assembly shaft, main shaft and
cluster assembly for power transmission to the wheel.
|
Steel
|
COMMON
FAULTS IN PETROL ENGINE
ENGINE DOES NOT START: It may be due to:
·
Discharged
battery
·
Cracked
distributor cap
·
Pitted
and dirty contact breaker points
·
Insufficient
gap of contact breaker
Rapidly burning of the breaker points: It may be due to:
·
Condenser
not earthed properly
·
Condenser
defective
·
Oily
breaker points
·
Points
gap too small
·
Weak
breaker arm spring
·
Excessive
generator voltage
SPARK PLUG FAILURE: It may be due to:
·
Incorrect
plug – gap
·
Poor
ignition and too much carbon deposited in the plug.
·
Burned
plug electrodes
·
Plug
produces poor spark
ENGINE MISFIRES AT HIGH SPEEDS: It may be due to:
·
Coil
or condenser defective
·
Point
gap too little
·
Worn
– out breaker plate assembly
·
Breaker
points bounce
HOW TO DIAGNOSE CARBURETOR PROBLEMS
Before attempting to
fix a carburetor problem, it is very important to come up with the correct
diagnosis.
Carburetors are
relatively simple devices. Their primary function is to deliver the correct
amount of fuel/air mixture at a given throttle opening (as selected by the
rider). However, as with all mechanical devices, carburetors will wear over
time and will also require periodic tuning and service.
Carburetor problems
generally fall into three areas: rich mixture, lean mixture, and incorrect
adjustment. Diagnosing carburetor problems is relatively easy and follows some
telltale symptoms.
THREE
CARBURETOR PROBLEMS
v RICH MIXTURE means the carburetor is delivering too much gasoline.
Typical symptoms of a rich mixture are:
Ø Poor fuel economy
Ø Sluggish acceleration
Ø Choke not needed from
cold starts
Ø Sooty or black spark
plugs
Ø Sooty or black muffler
end pipes
Ø Strong smell of
gasoline when machine is at idle
Ø Uneven running (will
often slow from regular idle rpm's and stop)
v LEAN MIXTURES means the carburetor is delivering too much
air. Typical symptoms of a lean mixture are:
Ø Backfires as the
throttle is closed (primarily during coast-downs)
Ø Lurching acceleration
Ø White or light grey
spark plugs
Ø Requires excessive
amounts of choke to run/start
Ø White or light grey
muffler end pipes
Ø Bluing (on chrome
systems) of the exhaust header down-pipes
v INCORRECT ADJUSTMENT applies to carburetors that have incorrect
adjustment of the air/fuel screw and the balance between two or more
carburetors - where fitted. Incorrect adjustment can produce any of the
previously noted symptoms. On multi-cylinder machines, with separate carburetors
for each cylinder, the following symptoms are typical of an adjustment problem:
Ø Poor overall
performance
Ø Rattling sounds from
the clutch
Ø Engine tends to stall
easily
Ø Erratic acceleration
Ø Poor fuel economy
Ø Misfires and/or
backfires
CORRECTING
CARBURETOR PROBLEMS
LEAN
MIXTURES: This condition is generally caused by the owner fitting
after-market accessories such as exhaust systems, air filter systems or
replacement carburetors of a different type or size. In addition, if the fuel
level in the float chamber is set too low, insufficient fuel will be drawn
through the main jet. Some carburetors have a slow speed fuel adjusting screw
that regulates the fuel/air mixture in the lower rpm range.
RICH
MIXTURES: This condition is primarily caused by dirty air filters, but it
could also result from the owner fitting replacement exhausts and/or carburetor
systems. If the fuel level is set too high in the float chamber, a rich mixture
will result.
Incorrect
Carburetor Adjustment: This situation is mostly caused by poor maintenance. With
the inherent vibration of all engines, carburetor parts (primarily adjusting
screws) tend to rotate, and therefore change their positions. Low-speed running
jets and multi-cylinder balancing screws are the items most prone to self-adjust
during normal operation and often require periodic corrections.
SYMPTOMS OF BAD OR FAILING SPARK PLUGS
Common signs of faulty spark plugs include slow
acceleration, loss of power, poor fuel economy, engine misfires, and difficulty
starting the car.
Without a spark, there would
be no way for fuel to ignite in the combustion chamber. Spark plugs have been a
critical component of the internal combustion engine for years. Spark plugs are
designed to transmit an electrical signal sent from the ignition coil at a
predetermined time to create a spark that ignites the air-fuel mixture inside
the combustion chamber. Each vehicle requires a particular type of spark plug
made from specific materials and with a designated spark plug gap that is set
by a mechanic during installation. Good spark plugs will burn fuel efficiently,
while bad or failing spark plugs can cause the motor not to start at all.
v SLOW ACCELERATION
The most common cause of poor
acceleration on most vehicles is a problem in the ignition system. Today's
modern engines have multiple sensors that tell the onboard computer and
ignition system when to send electric pulses to fire the spark plug, so the
issue may be with a faulty sensor. However, sometimes the issue is just as
simple as a worn out spark plug. A spark plug is composed of materials that
work together in order to produce a spark hot enough to ignite the air-fuel
mixture. When those materials wear out, the effectiveness of the spark plug is
reduced, which can significantly reduce the acceleration of the vehicle. If you
notice that your car is running sluggishly or does not accelerate as quickly as
it used to, it may be attributed to a spark plug that needs to be replaced.
v POOR FUEL ECONOMY
When a spark plug works correctly, it
helps burn fuel efficiently in the combustion cycle. When this occurs, your car
can achieve better than average fuel economy. When the plug is not functioning
optimally, it is frequently due to the fact that the gap between the spark plug
electrodes is either too close or too far apart. In fact, many mechanics will
take out spark plugs, examine them, and adjust the gap to factory settings as
opposed to replacing the spark plug entirely. If your vehicle has a reduction
in fuel economy, it very well could be attributed to a worn out spark plug.
v ENGINE IS MISFIRING
If the engine misfires, it's
typically due to an issue in the ignition system. Most of the time in modern
cars it's due to a sensor malfunction. However, it may also be caused by a
spark plug wire or the tip of the spark plug that connects to the wire being
damaged. An engine misfire can be noticed by intermittent stumbling or
sputtering sounds from the engine. If the engine is allowed to keep misfiring,
exhaust emissions will increase, engine power will decrease, and fuel economy
will drop. Because of all the potential problems associated with engine
misfiring issues, you should contact a mechanic as soon as you notice an engine
misfire.
v DIFFICULTY STARTING THE VEHICLE
If you have trouble starting your
vehicle, it could be a sign your spark plugs are worn. However as noted above,
the engine's ignition system is comprised of multiple individual components
that must work cohesively in order to function properly. At the first sign of
problems starting your car, truck or SUV, it's a good idea to contact a
certified mechanic to take a look at the cause.
Regardless of what the issue might be, the reality is that
spark plugs will eventually wear out. Being proactive about spark plug maintenance
can extend the life of your engine by hundreds of thousands of miles.
SYMPTOMS OF A BAD OR FAILING DISTRIBUTOR ROTOR AND CAP
Common signs include engine misfires, car not starting, the
Check Engine Light coming on, and excessive or unusual engine noises.
A running engine sends a large amount of electricity through
the ignition coils to the rotor, which turns inside the distributor. The rotor
routes the energy in a specific through the spark plug wires ultimately to the
engine’s cylinders in the correct firing order.
The distributor rotor and cap keep
the distributor’s contents separate from the engine and keep the distributor’s
working parts clean and tidy – while supporting the incredibly high volts of
energy and delivering them to the appropriate spark plugs. The spark plugs
utilize the spark from the distributor to ignite the fuel mixture, which is
what keeps the engine running.
High voltage runs through this entire
distributor system during the operation of your vehicle, but if there's an
issue this voltage won’t get distributed to the correct spark plugs to ensure
that your engine will run. Usually a faulty distributor rotor and cap will
produce a few symptoms that alert the driver that service may be required.
v ENGINE MISFIRES
Engine misfires can occur for a
number of reasons. Checking your distributor rotor and cap to see if they need
to be replaced is one way to ensure that everything is in solid working order.
v CAR DOESN’T START
When the distributor cap isn’t on
tightly or is malfunctioning, the engine is unable to send the spark through
the entire circuit required to move the cylinders – which ultimately make the
car run.
v EXCESSIVE OR UNUSUAL ENGINE NOISES
Your vehicle may make some very
strange noises if the distributor rotor and cap are malfunctioning –
specifically because the cylinders will try to fire but fail. You might hear a
tapping, clicking, or sputtering sound when the distributor rotor and cap are
failing.
Any time you have routine service performed on your vehicle,
ask that the ignition system be checked for defects or problems.
PROPER FIRING ORDER OF A 4 CYLINDER ENGINE
The typical firing order of Inline four cylinder engine is
1-3-4-2. Firing order in a multi-cylinder engine is arranged so that the
torsional moment is even and the load is uniformly distributed on longitudinal
direction of the crankshaft. An even firing order will increase the balance of
engine.
A 4-stroke engine completes four
strokes while crankshaft rotates 2 times. For a four cylinder engine hence an
even firing should happen every 180 degree rotation of crank.
The following principle should be
considered, in spacing out the firing
·
The
combustion should not occur simultaneously in two or more cylinders;
·
Successive
combustion in the cylinders that standing side by side should be avoided so
that the force transmitted to the crankshaft does not become one-sided.
COST ESTIMATION
|
Diesel Engine
|
||
|
Sr. No.
|
Component Name
|
Cost (INR)
|
|
1.
|
Diesel
|
150
|
|
2.
|
Injector
|
50
|
|
3.
|
Oil Pump
|
100
|
|
4.
|
Fuel
Pipe
|
50
|
|
5.
|
Rocker Box
|
380
|
|
6.
|
Diesel
Filter
|
225
|
|
7.
|
Gaskets
|
20
|
|
8.
|
Injector
Washer
|
5
|
|
10.
|
Exhaust Elbow
|
70
|
|
11.
|
Oil
Paint Varnish
|
40
|
|
12.
|
Thread
|
10
|
|
13.
|
Flexible
Exhaust Pipe
|
150
|
|
14.
|
M-seal
|
20
|
|
|
Total
|
₹1270
|
|
|
PETROL ENGINE
|
|
|
Sr. No.
|
Component Name
|
Cost (INR)
|
|
1.
|
Petrol
|
250
|
|
2.
|
Spark Plug
|
200
|
|
3.
|
Plug Cap
|
80
|
|
4.
|
Battery Water
|
30
|
|
5.
|
Air Filter
|
10
|
|
6.
|
Engine Oil (3.5L)
|
700
|
|
7.
|
Battery Terminals
|
60
|
|
8.
|
Petrol Oil Filter
Service
|
50
|
|
9.
|
Self-Start
|
400
|
|
10.
|
PVC Tape
|
10
|
|
11.
|
Clamps for cooling
|
75
|
|
12.
|
Professional Help
|
900
|
|
13.
|
Gear Oil (3L)
|
670
|
|
|
Total
|
₹3435
|
|
|
Transportation Cost
|
₹300
|
|
|
|
|
|
|
General Utilizing
Material
|
|
|
Sr. No.
|
Item
|
Cost (INR)
|
|
1.
|
Soap
|
20
|
|
2.
|
Fevi Quick
|
20
|
|
3.
|
Electrodes
|
30
|
|
|
Total
|
₹70
|
|
|
Total Cost
|
|
|
1.
|
Diesel
Engine
|
1270
|
|
2.
|
Petrol Engine
|
3435
|
|
3.
|
Transportation
Cost
|
300
|
|
4.
|
General Utilizing
Material
|
70
|
|
|
Total
|
₹5075
|
CONCLUSION
Our project “Maintenance of Diesel and Petrol Engine” has
been successfully completed. The deep
maintenance project brought together resources from every corner to participate
in some way however large or small. This in itself could be seen as the
greatest success factor in the project. Every person who participated in the project
gained valuable knowledge on the issue of diesel and Petrol engine maintenance
that so many continue to believe to be a non-issue. At the end of the project
it is clear to all of us who participated that improved maintenance practices
on diesel engines is the first line of control to reductions in emissions. To
simply re-state the objectives of the project and how the work has achieved
success on each point would be further repetition of what would by now be
obvious. The final judgement should be left to those who actually did the work
with this project and continue to carry on with the monitoring of emissions and
practicing improved engine maintenance long after the project has been
completed. During the case studies in the project the mechanics were asked to
provide feedback as to their thoughts on the new maintenance practices and the
future.
REFERENCES
|
The Project Idea
|
|
|
Project Queries
|
Er. Parul Dhiman
|
Others:
·
www.google.com
·
Encyclopedia
·
V.
Ganeshan (2007). Internal Combustion Engines. New Delhi: The Mc Graw Hill
·
Willard
W. Pulkrabeck. Engineering Fundamental Of The Internal Combustion Engines. New
Jersey: Prentice Hall.
·
John
B. Heywood (1998). Internal Combustion Engine Fundamentals. The Mc Graw Hill
Series.
