1. LUBRICATION AND
IGNITION SYSTEMS

2. LUBRICATION SYSTEMS
DEF OF LUBRICATION
 Lubrication is an art of admitting a lubricant
between two surfaces that are in contact and
in relative motion.

3. PURPOSE OF LUBRICATION
 To reduce friction and wear between moving
parts and there by the energy loss and to
increase the life of the engine.
 To cool the surfaces by carrying away the heat
generated in the engine components

4.  To provide sealing action i.e. the lubricating oil
helps the piston rings to maintain an effective
seal against the high pressure gases in the
cylinder from leaking out into the crankcase.
 To clean the surfaces by washing away carbon
and metal particles caused by wear.

5. MAIN COMPONENTS
In a reciprocating engine there are many surfaces in
contact with each other…..
 Main crankshaft bearings
 Big end bearings
 Gudgeon pin bearings

6.  Piston rings and cylinder walls
 Timing gears
 Camshaft and camshaft bearings
 Valve mechanism

7. REQUIREMENTS OF
LUBRICANTS
 Viscosity
 Physical stability
 Chemical stability
 Resistance against corrosion
 Pour point
 Flash point
 cleanliness
 Resistance against extreme pressure

8. TYPES OF LUBRICANTS
 Animal oils
 Vegetable oils
 Mineral oils
 Synthetic lubricants
 Greases
 Solid lubricants

9. TYPES OF
LUBRICATION SYSTEMS
 Petroil lubrication system
 splash lubrication system
 pressure lubrication system
 Dry lubrication system

10. PETROIL LUBRICATION SYSTEM
 Generally used for small 2-stroke engines.
 Simplest of all types.
 Certain amount of lubricating oil is mixed with petrol; usually the
ratio is 2%-3%.
 Due to high temperatures in the crank case, the petrol component
vaporizes leaving a thin film of lubricating oil on the crank case,
cylinder bearings, crankshaft and bearings

11. SPLASH LUBRICATING SYSTEM
 Employed for the engines of early motor cycles.
 One of the cheapest method.
 A scoop is made in the lowest part of the connecting
rod and the oil is stored in the oil trough.

12.  When the engine runs, the scoop causes the
oil to splash on the cylinder walls, each time it
passes through its BDC position.
 This affects the lubrication of engine walls,
gudgeon pin, main crankshaft bearings, big
end bearings.

14. PRESSURE LUBRICATION
SYSTEM
 This system used in almost universally in modern cars engines.
 An oil pump takes the oil from the wet sump .
 Delivers it through a filter to the main oil gallery at a pressure of 200
to 400 kpa.
 During its circulation, the oil gains heat from the various engine
parts, which is given out to the sump walls.

16. DRY-SUMP LUBRICATION SYSTEM
 Mainly employed for racing car engines where they has to operate
at very steep angles.
 Contains two pumps instead of one.
 Scavenge pump installed in the crankcase which pumps oil to a
separate reservoir.
 From that, oil is pumped by a pressure pump through a filter to the
cylinder bearings.

17.  The oil pressure is maintained at 400-500
kpa for the big end bearings while about 50-
100 kpa pressure is used for timing gears and
camshaft bearings.

20. OIL STRAINERS
 Oil strainer is attached at the inlet of the oil
pump to guard it against the entry of grit etc.,
 It is made of ordinary wire mesh screen.

21. OIL PUMPS
 Its function is to supply oil under pressure to the
various engine parts.
 It is generally located inside the crankcase below
the oil level.
 Driven from the end of the distributor shaft.

25. OIL FILTERS
• Used for removing the sludge and fine carbon
particles due to metal wear, especially during
the running period, particles of rust formed in
the engine contaminates the oil.

27. TYPES
 CARTRIDGE TYPE

28.  EDGE TYPE

29. IGNITION
SYSTEMS

30. FUNCTION
 The function of the ignition system is to
produce a spark in the engine cylinder
towards the end of the compression stroke

31. REQUIREMENTS
 It should provide a good spark between the
electrodes at the correct time.
 It should function efficiently over the entire
range of engine speed.
 It should be light, effective and reliable.

32.  It should be compact and easy to maintain.
 It should be cheap and convenient to handle.
 The interference from the high voltage should
not affect the functioning of the radio and
television receivers inside an automobile

33. TYPES OF
IGNITION systems
 Battery ignition system.
 Magneto ignition system.
 Transistorized coil ignition system.
 Capacitive discharge system.

34. BATTERY IGNITION SYSTEM
 Also called as an storage device.
 Ignition coil is the source of ignition energy.
 Coil stores the energy in the form of magnetic
field and delivers it at the instant of ignition in
the form of surge of high voltage current
through the high tension cables.

35.  Storage of energy in the magnetic field is based
on the inductive process.
 Consists of two coils of wire, one wound around
the other.
 Called as PRIMARY and SECONDARY windings.

43. MAGNETO IGNITION SYSTEM
 It is a special type of ignition system.
 With its own electric generator it can provide
the necessary energy for the system.
 It replaces all the components of the coil
ignition system except the spark plug.
 The magneto when rotated by the engine is
capable of producing a very high voltage.

44. layout

45. TRANSISTORIZED COIL IGNITION
SYSTEM
 Also called as high energy electronic systems.
 Provide a high voltage.
 Use electronic triggering to maintain the
required timing.

46.  The cam assembly and the contact breaker
are replaced by a magnetic pulse generating
system.
 It detects the distributor shaft position and
sends electrical pulses to an electronic control
module.
 The module switches off the current flow to
the primary coil, inducing a high voltage in the

47. CAPACITVE DISCHARGE
IGNITION system
 Capacitor is used rather than an induction coil to store the
ignition energy.
 The capacitance and charging voltage of the capacitor
determine the amount of stored energy.
 The ignition transformer steps up the primary voltage to
the high voltage required.

48. The CDI trigger box contains the capacitor, thyristor
power switch, charging device to convert the battery
low voltage to the charging voltage of 300v to 500v.
The advantage of using this system is that it is
insensitive to electrical shunts resulting from the spark
plug fouling.
Spark is strong but short.

50. THANK YOU