Mercedes of the S-class W202
1993-2000 of release
Repair and operation of the car
+ 1.2. General information
+ 2. Maintenance
+ 3. Engines
+ 4. Lubrication system
+ 5. Cooling system
+ 6. Heating, ventilation
- 7. System of ignition
7.2. Safety measures at repair of electronic system of ignition
7.3. Ignition coils
- 7.4. Spark plugs
7.4.2. Index of kalilny number
+ 7.5. Device of a preliminary warming up of the diesel
+ 8. Fuel system
+ 9. Transmission
+ 10. Running gear
+ 11. Steering
+ 12. Brake system
+ 13. Body
+ 14. Electric equipment
+ 14.2. Electrical circuitries
The spark plug consists of the central electrode, the insulator with the case and a side electrode. The side electrode is hermetically fixed in the insulator, the insulator is strongly connected with the case. Between the central and side electrode the igniting spark which sets fire to gas mixture slips. Readiness for start of the engine, an operating mode when idling depend on a spark plug, acceleration (dispersal) and the maximum speed. Therefore does not follow without the reason to refuse from ordered by the plant like spark plugs which is defined, among other things, by an index of kalilny number.
The index of kalilny number specifies degree of thermal loading of a spark plug. The index of kalilny number is lower, the thermal loading is higher. Therefore, the candle can take away better heat thanks to what prevents harmful kalilny ignition (an engine detonation). However, the candle with high thermal loading has that shortcoming that its temperature of self-cleaning is also higher. Therefore it becomes covered by a soot, in particular quicker in case the engine during driving does not reach the working temperature (the movement in the city, driving on short distances in the winter). As a rule, "cold" spark plugs (an index of kalilny number since 06) are applied in "hot" engines from which power units high power is required.
At use of copper cores (Cu) in the central electrodes of candles and the more so when using silver central electrodes heat conductivity and, thereby, thermal loading increases.
The index of kalilny number contains in a spark plug code which is deciphered as follows:
Spark plugs of Bosch
(1) W = a carving of M 14 x 1,25 with flat dense landing, SW 21 (the turnkey size); F = a carving of M 14 x 1,25 with flat dense landing, SW 16 (the turnkey size); N = a carving of M 16 x 1,25 with conic dense landing, SW 16 (the turnkey size).
(2) R = with the resistor for suppression of hindrances. Thanks to it, functioning of system of ignition does not render a radio noise.
(3) Kalilny index. The scale of kalilny numbers includes numbers from 06 – "cold" to 13 – "warm". At the same time the index 8 corresponds to old kalilny number 175 (earlier marking), 7 – 200, 6 – 225 etc.
(4) In = length of the cut part of 19 mm, a normal trajectory of the spark category; Д = length of the cut part of 19 mm, the stretched trajectory of the spark category; L = length of the cut part of 19 mm, extremely stretched trajectory of the spark category. Data on length of the cut part belong to spark plugs with flat dense landing. Addition of a letter "T" (for example, "DT") = 3 side electrodes.
(5) Material of the central electrode: without instruction = Cu-Ni – alloy, With = Ni-Cu – the combined central electrode, S = a silver central electrode, P = a platinum central electrode.
(6) About = a standard spark plug with the strengthened central electrode.
Spark plugs of Beru
(1) Diameter of a carving in mm, here: M 14 x 1,25.
(2) F = flat dense landing, To = conic dense landing, R = the noise suppressing resistor 5 kOhm / 10 kOhm.
(3) An index of kalilny number, interpretation, as well as at Bosch.
(4) Length of the cut part, interpretation, as well as at Bosch.
(5) Material of the central electrode: U = "ultra" (Ni-Cu – the combined central electrode), S = a silver central electrode, P = a platinum central electrode.
(6) About = the strengthened central electrode; R = with the protective resistor (for reduction of an obgoraniye of electrodes of spark plugs).
Kalilny numbers of spark plugs for the engines used on the S-class
The distance between electrodes in spark plugs makes 0,8 mm.