In the photo No. 1 a candle is shown, turned out of the engine, the operation of which can be considered excellent. The skirt of the central electrode has a light brown color, soot and deposits are minimal. The complete absence of traces of oil. The owner of this engine can only be envied, and there is a reason for this economical fuel consumption and the lack of the need to add oil from replacement to replacement.
On a photo No. 2 A typical example of a spark plug from an engine with increased fuel consumption. The central electrode is covered with a velvety black deposit. There are several reasons for this: a rich air-fuel mixture (improper carburetor adjustment or injector malfunction), clogged air filter.
In the third photo on the contrary, an example of an excessively lean air-fuel mixture. The color of the electrode is from light gray to white. There is cause for concern here. Driving on too lean a mixture and at increased loads can cause significant overheating of both the candle itself and the combustion chamber, and overheating of the combustion chamber is a direct way to burnout of exhaust valves. The skirt of the central electrode of the candle shown in the photo
№4 It has a characteristic reddish tint, this color can be compared with the color of red brick. This redness is caused by the operation of the engine on fuel containing an excessive amount of metal-containing additives. The long-term use of such fuel will lead to the fact that metal deposits form a conductive coating on the surface of the insulation, through which it will be easier for the current to pass than between the electrodes of the candle, and the candle will stop working.
Photo No. 5. The candle has pronounced traces of oil, especially in the threaded part. An engine with such candles after a long stop is used to “troit” for some time after starting, and as it warms up, operation stabilizes. The reason for this is the poor condition of the valve stem seals. There is an increased oil consumption. In the first minutes of engine operation, at the time of heating, a characteristic white-blue exhaust.
Candle in the photo number 6 turned out of the idle cylinder. The central electrode and its skirt are covered with a dense layer of oil mixed with drops of unburned fuel and small particles from the destruction that occurred in this cylinder. The reason for this is the destruction of one of the valves or the breakdown of the partitions between the piston rings with the ingress of metal particles between the valve and its seat.In this case, the engine "troit" is not ceasing, a significant loss of power is noticeable, fuel consumption increases by one and a half, two times. There is only one way out - repair.
Photo No. 7 this is the complete destruction of the central electrode with its ceramic skirt. The cause of this destruction could be one of the following factors: prolonged operation of the engine with detonation, the use of fuel with a low octane rating, very early ignition, and just a defective candle. Symptoms of the engine are the same as in the previous case. The only thing we can hope for is that the particles of the central electrode managed to slip into the exhaust system without being stuck under the exhaust valve, otherwise the cylinder head repair also cannot be avoided. But it depends on the person, whether he is sinful or not (a joke). If we talk about this particular candle, then God blessed its owner.
Photo number 8 last in this review. The candle electrode is overgrown with ash deposits, the color does not play a decisive role, it only indicates the operation of the fuel system. The cause of this build-up is oil combustion due to the development or occurrence of oil scraper piston rings. The engine has an increased oil consumption, when overgassing from the exhaust pipe a strong, blue smoke, the smell of the exhaust is similar to a motorcycle. If you want less problems for your engine, don’t forget about candles only when the engine refuses to work. The manufacturer guarantees trouble-free operation of a candle on a working engine of 30 thousand kilometers. But you, in turn, do not forget to check the condition of the candles with each oil change or on average every 10 thousand kilometers. First of all, it is the adjustment of the gap to the required value, the removal of carbon deposits. It is better to remove carbon deposits with a metal brush, from the sandblasting ceramics of the central electrode are destroyed, and you run the risk of getting a copy from photo No. 7.
I would also recommend changing the candles in places, this is due to the different temperature conditions of the cylinders.
"Treat" your auto-Kony.