How to determine later or early ignition on a car and motorcycle?
Any car must be serviceable, in every sense. All its components and mechanisms are necessary to ensure maximum efficiency. Not only comfort, but also safety depends on it. ensuring the maintenance of the operating cycle of the engine - one of the most important nodes. The operation of the engine itself depends on its operation. In domestic cars one of the most common problems is disruption of the ignition system. In its specific manifestation, this is a violation of ignition timing. Today we will pay special attention to this issue.
How does the ignition system work
These are special units that produce a spark that ignites the fuel in the cylinders.The spark itself is short, of low power. But it is very high in tension. Due to this, a spark arises between two electrodes on the spark plug.The moment of its occurrence must be consistent with the movement of the crankshaft and piston in the engine cylinder.
What is the moment
The very phrase "moment of ignition" should be understood literally. This is the time in which the fuel mixture in the cylinder begins to ignite. Not the duration of burning, but exactly the moment.This is due to the fact that the fuel mixture does not ignite instantly. Yes, it flashes very quickly (in a split second). However, these moments can be decisive for high-quality and complete combustion of fuel. The movement of the ignition front of the combustible mixture is measured 20-30 meters per second. It is a lot, but still not instant.
What is ignition advance
For a complete and high-quality, and most importantly, timely combustion of the fuel mixture, the earlier appearance of a spark in the cylinder is necessary.It occurs when the piston is still moving up, and a new portion of the mixture is still entering the cylinder. Thus, the mixture is prepared for combustion and compressed by the piston, and because of the aforementioned ignition delay, it is necessary that the spark occur a little earlier. This is called ignition advance.The degree of advance depends on the stable operation of the engine.
Early and later ignition
This is a delay or advance of the moment of ignition of the fuel mixture in relation to the position of the piston in the cylinder.In this case, detonation often occurs. This explosive combustion of the fuel mixture in the cylinders, which is very dangerous for the connecting rod-piston group. Detonation has a large load on the crank. Therefore, the owners of cars that provide the ability to change the leading angle, are faced with the need to adjust. Do it yourself.
How to determine later or early ignition?
Signs of early ignition are the following symptoms:
- Metal ringing in the area of the cylinder block.
- Floating idling speed.
- Dips when the engine is running, slower speed.
Signs of a late ignition angle:
- Power loss during acceleration.
- Increased fuel consumption.
- Accelerated formation of soot.
- Overheating of the engine in all modes.
Another way to determine later or early ignition in a car is the characteristic exhaust sound. It occurs due to misalignment of the exhaust gas phases.And later, and early ignition is equally harmful to any engine. Therefore, the adjustment must be done necessarily.
Anticipation on domestic cars
A good way to determine if the VAZ-2106, -2109 is later or earlier ignited is to follow the operation of the heated engine at idle.It should work smoothly, without failures and not swing at work. When the ignition is wrong, it will definitely twitch. This is due to the occurrence of jet moments in the connecting rod-piston group, which are transmitted to the cylinder block. The rest of the symptoms are completely the same for all carburetor engines.
About diesel engines
How to determine the early or late ignition of a diesel engine? One of the main differences of this engine from a gasoline engine is that the fuel does not ignite from the spark plug, but from its contact with heated and compressed air in the combustion chamber. There is a slightly different principle.But the concept of ignition timing is present here. Fuel is supplied at the very end of the compression stroke, not earlier and not later. Angle setting on a diesel engine is a change in fuel injection timing.How to find out later or early ignition on a car engine? Since there are no spark plugs in such an assembly, the most important component, the high-pressure fuel pump (TNVD), is engaged in the valve timing. The correct timing angles depend on its settings. Signs of early or late ignition on a diesel engine are the same as on a gasoline engine. However, diesel is much more sensitive to the angle. Incorrect installation of ignition can quickly destroy the engine. And one more thing - with the wrong timing angles, the engine may not start at all. Either the launch will be difficult.
How to determine later or early ignition, the candles?
Candles are a great indicator of engine condition. By their appearance can be judged on various problems, including the correctness of the angle set. Since during late ignition the fuel does not burn to the end, its part will settle on the walls of the combustion chamber and, of course, on the candle. Thus, in the later ignition they will be smoked, with a thick layer of soot.With early possible appearance of the fuel on the elements ("wet" candles). This is another way to determine if the VAZ-2109 is later or earlier ignited. Ash can also form on the electrode.When the engine is running, it heats up quickly and promotes oil burning. It should be borne in mind that not only the candles can be judged on the correctness of the angle. For this there are other signs that are mentioned above. The condition of candles can serve as an indirect confirmation of the results of observations.
How to determine later or early ignition on a motorcycle? Since two-stroke engines are mainly installed on such vehicles, incorrect adjustment of the lead time greatly influences the operation of the phases. Signs of incorrect settings here are exactly the same as on four-stroke engines.Only on motorcycles will the engine be worse in addition to start up and it is unstable to work at idle.
Differences of various ignition systems
On carburetor engines, the system is contact and non-contact. In the first case, the distribution of high-voltage discharges from the coil occurs by mechanical interruption of the contact through the rotation of the interrupter. The latter rotates with the crankshaft. In the second case, the distribution of pulses occurs using an electronic control unit. It receives a signal from a special sensor.In both cases, the adjustment takes place by turning the housing of this distributor (with contacts or with a sensor). Angles of rotation are small, within two degrees. But they play a huge role in the formation of the correct valve timing.
How to find out, early or late ignition on a car engine? To do this, use a special device - a strobe. This is a lamp in the housing, flashing depending on the operation of the ignition system. The device is connected to the system and receives pulses that simulate the appearance of a spark in the first cylinder. After that, the plug on the flywheel housing at the bottom of the engine is removed so that the flywheel can be seen. Then the nut holding the ignition distributor is loosened. The engine starts and the strobe is sent to the flywheel. When the timing is right, the label on the flywheel at the time of the strobe flash will coincide with the one on the crankcase. By turning the ignition distributor, you can shift their coincidence. The marks when the strobe lamp is on will appear stationary. After their coincidence on the flywheel and the crankcase, you can tighten the distributor mounting nut and check the operation of the engine.It should work smoothly, quickly gain momentum and not twitch at idle.
As you can see, there are many ways how to determine if later or early ignition is exposed on the car. Properly tuned system will ensure reliable and stable engine operation.