CHAPTER 1:FUEL DELIVERY
SYSTEM
CARBURETOR SYSTEM
FUEL INJECTION SYSTEM
PETROL FUEL SYSTEM
DIESEL FUEL SYSTEM
FUEL INJECTION SYSTEM
FUEL DELIVERY SYSTEM
INTRODUCTION
1.1 PETROL FUEL SYSTEM
CARBURETOR SYSTEM
BERNOULLI’S PRINCIPLE
V P
COMPONENTS FUNCTIONChoke valve To enrich the mixture during cold
startThrottle valve Control the amount of air to be
pulled into the combustion chamberFloat valve Control the amount of fuel contain
inside the float chamberFloat chamber Act as the reservoir of the fuelJet Control the correct amount of fuel at
the venturi especially while idling
Idling system – supplies air-fuel mixture during closed throttle operation
Operation of Carburetor System
Float bowl in the carburetor is supplied with fuel from fuel tank by fuel pump
Air passes through venturi and causes fuel to pushes out from jet
As throttle valve opens more air passes through venturi
ELECTRONIC FUEL INJECTION
COMPONENTS
EFI SYSTEMS
EFI COMPONENTS FUNCTIONManifold Absolute Pressure (MAP sensor)
Reads atmospheric pressure
Coolant Temperature (CTS sensor)
Report engine coolant temperature
Oxygen sensor (02 sensor) Measure the amount of oxygen in the exhaust gas
Engine Speed Sensor Measure how fast the engine crankshaft turningThrottle Position (TPS Sensor) Reports the position of the throttle valveElectronic Control Module (ECM)/Electronic Control Unit (ECU)
Receive data from all the sensors and calculate how much fuel to inject
Injectors Control the amount of fuel to be injected
Operation of EFI SystemECM continuously receives all data from the
sensor
ECM check the data and compare with the data stored in look-up table in its memory
ECM decides when to open the injectors and for how long
COMPRESSION POWER EXHAUSTINTAKE
A)
B)
SI ENGINE
CI ENGINE
STATE THE DIFFERENCES??
WHICH ONE CI ENGINE AND SI ENGINE??
Description
SI Engine CI Engine
Fuel Gasoline, a highly volatile fuel. Self-ignition temperature is high.
Diesel oil, a non-volatile fuel. Self-ignition temperature is comparatively low.
Introduction of fuel
A gaseous mixture of fuel and air is introduced during the suction stroke. A carburetor is necessary to provide the mixture.
Fuel is injected directly into the combustion chamber at high pressure at the end of the compression stroke. A fuel pump and injector are necessary.
Load control
Throttle valve controls the quantity of mixture introduced.
The quantity of fuel is regulated in the pump. Air quantity is not controlled.
Ignition Requires an ignition system with spark plug in the combustion chamber.
Self-ignition occurs due to high temperature of air because of the high compression.
Compression ratio
6 to 10. Upper limit is fixed by antiknock quality of the fuel.
16 to 20. Upper limit is limited by weight increase of the engine.
1.2 DIESEL FUEL SYSTEM
Injector Nozzle
Diesel Fuel Filter
Rotary-Distributor
Inline-Plunger Injection
TYPES OF DIESEL FUEL
PUMPS
Inline Fuel Injection Pump
Disassemble Inline fuel injection pump Actual position Inline fuel injection pump
Effective stroke-amount fuel injected
• to control the fuel to the exact stroke
Distributor Fuel Injection Pump
Actual position Distributor fuel injection pump
Sectioned view Distributor fuel injection pump
DIESEL PISTON
Recommended
