Two ignition systems - contact and non-contact. And each has its own advantages and disadvantages. But there are also differences in design. The runner on the distributor in a non-contact system requires less attention. And it's much easier to replace it.
There are two ignition systems - contact and non-contact. The main difference between them is the method of applying a pulse to the ignition coil. The basis of both systems is the ignition distributor, which is more often called the distributor. With its help, a spark is formed and directed to the desired cylinder.
Contact ignition system
An excellent example is domestic cars of the "classic" VAZ family, produced before the end of the 90s. The spark was formed using a contact group (hence the name of the system). But such designs quickly became outdated, they were replaced by more reliable ones. After all, if there are moving contacts, then there is also friction, which destroys the unit.
This is the main drawback of the system - the rapid destruction of the contact group, burning, since the current passes through it very large. On top of that, you can add a constant gap adjustment. If you set the wrong one, then the car will either not start at all, or it will work intermittently, and you will feel a lack of power and agility, since the spark will be very weak and will not be able to ignite the mixture.
The slider in the distributor plays a huge role. With its help, high voltage from the output of the ignition coil is supplied to the spark plugs in the cylinders by means of high-voltage wires. The slider consists of:
• frame;
• resistance;
• weights for adjusting the ignition timing;
• contacts.
The main malfunctions are the burnout of the resistor, the resistance of which should be in the range from 5 to 6 kOhm. Due to the fact that the slider itself has a low cost, it turns out to be much easier to replace it completely. To do this, remove the distributor cover by pulling back the latches. Using a screwdriver, unscrew the two bolts and remove the slider cover.
Under the cover there are weights necessary to adjust the ignition timing. It is advisable to wash them with solvent or kerosene, cover with grease. But this is in the event that the mechanism has no defects. If there is a breakdown, then it is necessary to replace the weights, the cover of the slider and the cover of the distributor.
Contactless ignition system
It is much simpler and more reliable and requires less maintenance. A good example of the use of such systems is the VAZ 2108-21099. The spark is generated by a Hall sensor installed in the base of the ignition distributor. The sensor performs the functions of a contact group, only in a slightly different way. A kind of metal skirt with slots is located on the distributor shaft; a sensor is located opposite it.
When the metal part of this skirt passes near the sensor, a pulse arises in the latter, which is fed to the switch. The impulse is very weak, therefore it must be amplified (this function is performed by the switch), and only then fed to the coil, from the output of which the high voltage goes to the central contact of the distributor cover.
And already from the central contact, high voltage is distributed to the spark plugs. It is necessary to disassemble and change the slider if the contacts or resistance on it have been destroyed. The whole procedure is much easier than with the contact system.
Using a Phillips screwdriver, unscrew the two bolts that secure the distributor cover, remove it. The runner is attached to the distributor shaft with a spring clip, so you just need to pull it to remove it. Installing a new one is as easy as removing the old one. It is impossible to put the slider incorrectly, since the end of the shaft in section looks like a semicircle.
