TYPES OF ENGINES AND ENGINE SERVICING.pptx

Engines in Automobile Engineering

An engine is the heart of an automobile. It converts chemical energy of fuel into mechanical energy that drives the vehicle. Based on design, fuel, and operating principles, automobile engines can be classified into different types.

1. Based on Fuel Used

Petrol (Gasoline) Engines
Operate on spark ignition (SI) principle. A spark plug ignites the air–fuel mixture. Used widely in cars and two-wheelers due to smooth operation and high speed.

Diesel Engines
Operate on compression ignition (CI) principle. The air is compressed to high pressure and temperature, and fuel is injected at the end of compression stroke. Known for higher torque and fuel efficiency.

Gas Engines
Run on CNG, LPG, or hydrogen. They are cleaner alternatives with reduced emissions.

2. Based on Ignition Method

Spark Ignition (SI) Engines – Use spark plug for ignition (mostly petrol).

Compression Ignition (CI) Engines – Fuel ignited by compressed hot air (mostly diesel).

3. Based on Number of Strokes

Two-Stroke Engines
Complete power cycle (intake, compression, power, exhaust) in two strokes of the piston. Lighter, higher power-to-weight ratio, but less fuel efficient and more polluting.

Four-Stroke Engines
Complete cycle in four piston strokes. More fuel efficient, durable, and commonly used in cars, trucks, and buses.

4. Based on Number of Cylinders

Single-Cylinder Engines – Simple, compact, used in two-wheelers.

Multi-Cylinder Engines – Provide smoother operation and higher power, used in cars, buses, and heavy vehicles (4, 6, 8, or more cylinders).

5. Based on Cylinder Arrangement

Inline Engines – Cylinders in a single straight line (common in most cars).

V-Engines – Cylinders arranged in two banks forming a “V” shape (V6, V8 engines). Compact and powerful.

Flat or Boxer Engines – Cylinders placed horizontally opposite each other, offering low center of gravity (used by Subaru, Porsche).

Radial Engines – Cylinders arranged around a central crankshaft (mainly in aircraft, rarely in automobiles).

6. Based on Cooling Method

Air-Cooled Engines – Use fins and air circulation (common in motorcycles).

Liquid-Cooled Engines – Use water or coolant with radiator (common in cars and trucks).

7. Based on Valve and Fuel System

Naturally Aspirated Engines – Air enters cylinders at atmospheric pressure.

Turbocharged/Supercharged Engines – Compressors force extra air into cylinders for more power.

MPFI, GDI, CRDI Systems – Advanced fuel injection technologies improving efficiency and emissions.

Conclusion

Automobile engines are classified based on fuel type, ignition method, strokes, cylinder number/arrangement, cooling system, and induction method. Each type has its own advantages, applications, and limitations, and the choice depends on vehicle requirements like power, efficiency, cost, and emission norms.

1. AUTOMOTIVE ENGINEERING P.CHINNA RAO ASSISTANT PROFESSOR DEPARTMENT OF MECHANICAL ENGINEERING RGUKT-AP SRIKAKULAM

2. Learning Outcomes To know different types of AUTOMOTIVE ENGINES Discussion on Engine servicing

3. Types of Chassis Based on frame: 1. Ladder frame 2 . Backbone frame 6. ULSAB frame 3 . Tubular space frame 4 . Monocoque frame 5. Aluminium space frame 7. Carbon fibre frame Based on Assembly: 1. Conventional Chassis 2 . Integral Chassis 3 . Semi Integral Chassis Based on Engine Location: 1. Semi forward chassis 2 . Full Forward 3 . Center Engine 4 . Rear Engine

4. Power unit of an automobile consists of an internal combustion engine. In most of the vehicles, it is usually mounted at the front end of the automobile. The clutch and gear box are placed immediately behind it.. Power Unit of Automotive The three components are assembled into a single unit.

5. Lubrication System IC engines are made up of many moving parts. Due to continuous movement of two metallic surfaces over each other, there is continuous wearing of moving parts, generation of heat and loss of power of the engine.   To prevent all these harmful effects the lubrication system is essential.   The purpose of lubrication system as follows: Reducing the friction   cooling effect Sealing effect Cleaning effect There are different types of lubricants such as Solid lubricants (Graphite, mica, Talc powder ), Liquid lubricants (animal Fat oil, vegetable oil, mineral oil) and semi solid (Grease) The parts which require lubrication are: Cylinder walls and piston Piston pin Crank shaft and connecting rod bearings Cam shaft bearings

6. Types Lubrication Systems Mist lubrication system Dry sump lubrication system Wet sump lubrication system S plash lubrication system Semi pressure lubrication system Full pressure lubrication system

7. Types of Automobile E ngines The classification of IC engines are based upon the following parameters. Type of cycle Type of fuel Cycle of combustion Method of ignition Number of cylinders Method of cooling Arrangement of cylinders Speed of engine Method of governing etc.

8. Automobiles need maintenance from time to time. Like humans are required to maintain hygiene, similarly automobiles also need to be kept clean. Automobiles have to run on dirty roads and in a polluted environment. They run on uneven roads with potholes and other obstructions, and are therefore subjected to loads which damage them. Therefore, there is a need for regular maintenance and servicing of automobiles, which is usually done in auto workshops or auto service stations. One of the most costly repairs in the automotive industry is engine replacement. Fortunately, with proper routine maintenance, you can usually avoid this expensive problem and maintain a functioning engine.  Regular Engine Maintenance: Engine maintenance typically includes the following to help prolong the life of your engine : Spark Plug Replacement Spark Plug Wire Inspection A Thorough Inspection Of All Engine Components Air And Fuel Filter Replacement Where Necessary Engine Servicing

9. Introduction to Vehicle Service Procedure: You may have noticed that authorized automobile service centers adopt certain procedures during the service of a vehicle. Common Activities in the Workshop : Job card and its filling procedure Washing of vehicle and Washing Procedure Engine minor tune up Oil replacement Checking of battery—electrolyte level and top-up Clutch and brake-free play and their adjustment Lighting system, its various parts and their checking Identification of greasing points of wheelers and procedure of greasing Checking of tyre inflation and procedure of inflation

10. Engine maintenance tips : Change Engine oil at Regular Intervals Keep check on the cooling system Check the air filter and get it cleaned/changed Look for leaks Don’t keep going on reserve fuel Check the belts Don’t ignore to check engine light Replace fuel filter Replace spark plugs and wires Your engine doesn’t like revving just to come to a complete halt