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Diagnosis of engine appearance of spark plugs
1. Normal candle. Brown or grayish-yellow color and a small electrode wear. Exact values candles for heat engine and operating conditions.
HELPFUL ADVICE When replacing spark new place candles with the same characteristics of those recommended by the manufacturer. |
2. soot. Dry deposition of soot indicates a rich fuel mixture or after the ignition. It causes misfiring, hard starting engine and an unstable operation of the engine. Check for clogged air filter are serviceable if the coolant temperature sensor and the intake air.
HELPFUL ADVICE Use a "hot" candle. |
3. Oil deposits. Oiled electrodes and insulator candles. The reason - the oil from entering the combustion chamber. The oil enters the combustion chamber through the valve guides or piston rings. Causes hard starting, gaps in the cylinder and "jerking" the engine running. Needed to repair the cylinder head and piston engine. Replace the spark plug. 4. The metal plaque. Deposits on the skirt insulator iron oxides brick-red color of the iron-containing anti-knock additive (ferrocenes) to gasoline. Postponed smooth, dense layer. When the motor with a heavy load under high temperature and pressure in the combustion chamber oxides are reduced in the current paths of pure iron, trailing the center electrode to the "masses." This causes a misfire and the resulting drop in engine power and increases fuel consumption. In addition, can be damaged by the catalytic converter exhaust gas, overheated when hit by unburned fuel in the engine cylinders. Plaque is practically impossible to remove by mechanical means, it does not fade during long-term driving at a high speed. If the plaque appeared on the new candles after a short run, a change of dressing.
HELPFUL ADVICE If you can not immediately replace the spark new, try to remove the plaque, candle dipping ten minutes skirts insulators in phosphoric acid or a rust converter (containing phosphoric acid). After that, clean the coating of non-metallic brush (an old toothbrush is possible) and rinse with water first candle, then gasoline. |
5. Melted electrodes. Early ignition. Insulator white, but may be contaminated due to the spark gaps and falling on his deposits from the combustion chamber. It may damage the engine. It is necessary to check that the type of spark plug, clean spray nozzles and the fuel filter, the systems of cooling and lubrication. 6. Ash deposits. Light brown sediments crusted central and side electrodes. Stand out from the additive to the oil or gasoline. Large quantities can lead to isolation of the electrodes the spark that causes gaps in sparking and interruptions during acceleration. If excessive deposits formed in a short time or low mileage, replace the valve seals valve guides to prevent oil from entering the combustion chamber.
HELPFUL ADVICE If deposits are formed by stable long run, the reason is the quality of petrol - change their place of refueling. |
7. Insulator cracked or chipped. Detonation. This can result in damage to the piston. Make sure that the octane number of gasoline as desired. 8. Mechanical damage. Damage may be caused by foreign objects trapped in the combustion chamber, and in the case it is too long spark electrodes can catch piston. This leads to the destruction of the candle, and disconnect the cylinder can damage the piston. Remove the foreign object from the cylinder, and (or) replace the spark plug.
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