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Spark plugs - general description

Spark plugs have a thread diameter of 14 mm. Manufacturers recommend candles of a certain type, but you can use a suitable spark with appropriate heat range of other manufacturers. The distance between electrodes is 0.8 mm candles. Spark plugs should be cleaned sandblasted every 10,000 km. At the same time set the appropriate electrode spacing. When adjusting the distance never to bend middle electrode, as may burst porcelain insulator.

Before unscrewing the spark check to niches of candles were not any foreign objects. Caught in the hole candles washers, bolts or stones destroy valves, valve seats and cylinder head when you first start the engine. In appearance, the candle can be concluded about the candle adjusting the carburetor, the mixture state and the state of the engine (pistons, piston rings, and so on. D.)

Coal deposits

Symptoms: The presence of soot indicates pereobogaschenie air-fuel mixture or low intensity spark. It causes misfiring complicates start and leads to instability of the engine. Recommendation: Check whether the air cleaner is not blocked is not too high fuel level in the float chamber, if not jammed choke and not too worn contacts. Try to use candles with longer insulator that raises resistance to contamination.

Oiling

Symptoms: oily contamination spark causes wear stem seals. The oil enters the combustion chamber through the valve guides or worn piston ring. It causes misfiring complicates start and leads to instability of the engine. Recommendation: Perform mechanical recovery work and replace candles.

Overheat

Symptoms: Porous, white insulator, erosion of electrodes and the absence of any deposits. It leads to a reduction in the life of the candle. Recommendation: Check whether the requirements of the Specifications number of installed glow of candles, correctly exposed ignition timing is not served there too lean air-fuel mixture leaks vacuum inlet pipeline and whether valves are jammed. Check the coolant level as well, and blockage in the radiator.

Too early ignition

Symptoms: Electrodes are melted. The insulator is white, but may be contaminated due to a misfire, or falling into the combustion chamber of foreign particles. It may lead to engine damage. Recommendation: Check the number of installed glow of candles, the ignition timing, the quality of the mixture (not too depleted), blockage in the cooling system is functioning normally and the lubrication system.

Electrically conductive gloss

Symptoms: Insulator has yellowish color and the polished look. It speaks about sudden rise in temperature in the combustion chambers at sharp acceleration. Ordinary deposits while melted, getting kind of lacquer. It leads to misfire at high speeds. Recommendations: Change candles (colder, while maintaining the driving style).

The closure of the electrodes

Symptoms: Waste combustion products enter the inter-electrode space. Solid deposits accumulate, forming a bridge between the electrodes. Leads to failure of the ignition cylinder. Recommendation: Remove deposits from the electrode area.

The normal state of candles

Symptoms: Gray-brown color and easy deterioration of electrodes. Heat range spark for the type of engine and its general condition. Recommendations: At replacement of candles set the candles of the same type.

Peploobrazovanie

Symptoms: Soft brownish deposits on one or both of the spark plug electrodes. The source of their formation are applied additives to oil and / or fuel. Excessive accumulation can lead to isolation of the electrodes and cause misfiring and unstable engine performance during acceleration. Recommendation: With the rapid accumulation of sediment change stem seals that will prevent oil from entering the combustion chamber. Try to change the brand of fuel.

Wear

Symptoms: Rounding electrodes with a small accumulation of deposits on the working end. Color normal. It leads to difficulty starting the engine in cold damp weather and increased fuel consumption. Recommendations: Change candles on new of the same type.

Detonation

Symptoms: Insulators can be cleaved or cracked. It can cause damage to the insulator as sloppy technique adjustment of a candle backlash. It can cause damage to the pistons. Recommendation: Use caution when adjusting the gap on the new spark. Avoid jerking the engine.

Splashing

Symptoms: After misfire for a long period of time deposits can disintegrating maintaining the operating temperature in the combustion chamber. At high speeds of deposition flakes come off the piston and stick to a hot insulator, causing misfiring. Recommendations: Replace candles or smooth out and replace the old ones.

Mechanical damage

Symptoms may be caused by the ingress of foreign material into the combustion chamber, or occur when the piston stroke about too long candle. Lead to refusal of functioning of the cylinder and piston damage. Recommendation: Remove from the engine extraneous particles and / or replace the spark shorter.