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Spark plug

Spark plug comprises a central electrode with the insulator body and the electrode mass. A center electrode mounted in a gastight insulator. The insulator is firmly connected to the housing. Between the central and lateral electrode slips spark, igniting the fuel-air mixture. From spark plugs depend on the properties of starting the engine, the nature of idling, acceleration of the car and its maximum speed. It is therefore not recommended without special reason to move from the candles recommended by the manufacturer, to spark another type.

Thermal performance (heat rating) candle is a measure of the degree of heat stress in the engine spark under certain conditions. The lower the number of candles glow, the greater its ability to withstand heat stress. The candle can better dissipate heat, thereby preventing damage due to pre-ignition (detonation engine). Candle with a high ability to withstand thermal load has the disadvantage that the temperature self-cleaning is accordingly higher. This candle is more prone to bloated, especially when the engine often does not reach its operating temperature during operation (urban cycle, the movement of short segments in winter). As a rule, the "cold" candles (with a heat rating number starting with 06) are mounted on the "hot" engines, ie. E. On the power units, which are required more power.

Heat range is contained in the designation of a candle. Designation candle stands as follows:

Spark plugs firm BOSH

Example

WR 7 DC

1 2 3 4 5

1 - W = M 14x1,25 thread with flat sealing surface, SW 21;

F = M 14x1,25 thread with a flat sealing surface, SW 16;

M = M 18x1,5 thread with a flat sealing surface, SW 25;

H = M 14x1,25 thread with a conical sealing surface, SW 16;

D = M 18x1,5 thread with a conical sealing surface, SW 21;

SW = Width key.

2 - R = resistor with RFI. It has no effect on the operation of the ignition system.

3 - heat rating. Scale mantle numbers from 06 "cold" to 13 "warm." The value of the glow of 7 corresponds to the value 175 under the old scale, 6 - 200; 5 - 225 and t. D.

4 - A = thread length 12.7 mm normal spark;
The thread length = 12.7 mm, stretched a spark;
C = thread length 19 mm, normal spark;
D = thread length 19 mm, stretched spark.

5 - the material of the central electrode: Without designation = alloy of chromium and nickel;
C = compound of nickel and copper,
S = Silver,
P = platinum
O = standard candle with a reinforced central electrode.

Due to the copper core center electrode, and an even greater extent by the central electrode of silver, the thermal conductivity is significantly increased.

BERU Spark

Example:

14, R 7 DU

1 2 3 4 5

1 - thread diameter in mm, is 1.25 x M14

2 - structural feature, for example, for a flat sealing surface for K resistor RFI

3 - heat rating (as BOSH)

4 - thread length (as BOSH)

5 - electrode material, such as U for copper core

MAZDA production model in most cases equipped with NGK spark plugs or Nippondenso. The rules are different for different manufacturers. When replacing the spark can be installed BOSH and BERU.