Automotive engines are available in both gasoline and diesel configurations. These engines are considered internal combustion because the ignition and burning takes place inside the engine.
These systems require an exact air/fuel mixture that arrives in the combustion chamber at the correct time. The combustion chamber is the space between the top of the piston and the cylinder head. It’s an enclosed area that the fuel and air mix is ignited and burned.
The piston fits into a hollow metal tube, called a cylinder. The piston moves up and down in this cylinder. The reciprocating motion must be converted to a rotating motion before it can actually be connected to the wheels of the vehicle.
Automotive Engine Principles
This change of motion is accomplished by connecting the piston to a crankshaft with a connecting rod. The up-and-down movement of the piston is converted into a rotating motion via the connecting rod. The top of the connecting rod attaches via a wrist pin to the piston that is moving up and down in the cylinder.
The bottom end of the connecting rod attaches to a round crankshaft journal, and this is how the reciprocating motion is converted to rotating. At the end of the crankshaft is the flywheel that transfers engine power through the drive-train to the wheels.
The engines flywheel along with the rotating crankshaft have all been matched and balanced from the factory. This is done to remove vibration caused by high rotation speeds.
A flywheel can be connected to a manual transmission through a clutch and pressure plate to provide direct physical connection with no slipping. On an automatic transmission the flywheel is connected to a torque converter that is filled with specialized hydraulic fluid that provides a very strong fluid coupling between the engine and automatic transmission.
Combustion makes the automotive engine move
In order to have complete engine combustion the exact amount of fuel must be mixed with the right amount of air. This air fuel mixture must be compressed in a sealed area, and then ignited by a spark created by the ignition system at exactly the right moment.
Each cylinder should receive the same amount of air fuel and spark if the engine is to run efficiently. Although the combustion must occur in a small sealed area it is necessary to let air and fuel in, and exhaust gases out.
To accommodate these requirements engines are fitted with valves. There are at least two valves at the top of each cylinder (the larger is intake). The fuel mixture enters the standard automotive engine through the intake valve.
After the fuel has been burnt the exhaust gas exit through the exhaust valve. A rotating camshaft, driven by the crankshaft, opens and closes the intake and exhaust valves at exactly the right time. Camshafts have raised sections that are called camshaft lobes.
As the camshaft rotates these lobes will lift the valve open by pushing it away from its seat. Once the cam lobe rotates out of the way the valve is forced closed by a high-pressure spring. Some camshafts can be located inside the engine block and operate the valves via push rods.
Modern-day engines now have the camshaft mounted on the cylinder head area, cutting down on the length of moving parts. These are known as overhead cams. This is an oversimplified basic introduction to automotive engine operation. Dig into the articles below for more information about the engines operation, diagnosis and repair.
How to know if your automobile engine is having issues
– A noisy engine may be the first indication to drivers that a major problem is heading their way.
– If your oil warning light comes on and you discover a low fluid condition you have to find out where the stuff is going.
Automotive Tests to Check Your Engine
– A compression test can provide a lot of good information about the overall condition of your engine.
– If a compression test provided some low numbers on a few cylinders. A leak down test may directly point to the problem.
– When your engine is running rough a power balance test can isolate the cylinder with the problem.
– Speaking of rough running engines and balance, A fuel injector balance test can pin point injector issues.
– The vacuum test is the fastest and easiest way to start analyzing a performance problem or rough running condition.
– An oil pressure test can provide a good indication of the internal condition of your engine and just how worn the bearings are.
Please note that there is a $59.17 (plus ss & tx) vehicle diagnosis charge for vehicles that do not complete repairs with our facility.
Thank you for your understanding.
Reference from YouFixCars.com Retrieved from http://www.youfixcars.com/automotive-engine.html