E39 series BMW 5

since 1996-2001 of release

Repair and car operation

+ Introduction
+ Maintenance instruction
+ Current leaving and service
+ Engine
+ Systems of cooling, heating
+ Power supply system and release
- Engine electric equipment
   - Ignition system
      Security measures at work with ignition system
      Removal and installation of the coil of ignition
      Removal and installation of the sensor of a detonation
      Check and replacement of the sensor of impulses
      Removal and installation of the tip of a spark plug
      Removal and DME control unit installation
      Spark plugs
   + System of preheat of the diesel engine
   + charge and start Systems
+ Manual transmission
+ Automatic transmission
+ Coupling and power shafts
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ electric equipment Schemes
+ System of onboard diagnostics

Саркисян столото

Spark plugs

General description and parameters

Spark plugs have the turnkey size of 16 mm. Producers recommend candles of a certain type, however it is possible to use suitable candles with the corresponding kalilny number of other producers. It is necessary to replace spark plugs through each 20 000 km or 2 years. Before a vyvinchivaniye of candles check, that in niches of candles there were no extraneous subjects. Got to openings of candles of a washer, bolts or stones will destroy valves, saddles of valves or a head of cylinders at the first start of the engine.

The spark plug consists of the central electrode, an insulator with the case and a lateral electrode. The central electrode is tightly connected with an insulator, the insulator is strongly connected with the case. The spark is formed between central and lateral electrodes. Idling characteristics depend on a spark plug, acceleration and the maximum speed of the car starting readiness. Thereof it is not necessary to apply candles, distinct from what are recommended by manufacturer. Key parameter of a spark plug is the kalilny number. It characterizes thermal loading ability of a candle under certain conditions operation. Candles are chosen in such a manner that they under all possible service conditions reach self-cleaning temperature. The kalilny number of a candle is lower, the higher it resistance in relation to kalilny ignition and the is higher resistance to pollution.

Kalilnoye number is specified in a candle code. The code has the following structure:

For example

Bosch candles

F 8 L


1 2 3

4 5 6

1 — W - a carving of M 14 x 1.25 with flat consolidation, on a turn-key basis 21; F-a carving of M 14 x 1.25 with flat consolidation, on a turn-key basis 16; H-a carving of M 14 x 1.25 with konusny consolidation, on a turn-key basis 16.

2 — Kalilnoye number. Can be from 06 (a "cold" candle) to 13 (a "warm" candle). Thus number 8 corresponds to kalilny number 150 (former designation), 7-175, 6-200 etc.

3 — B - length of a carving of 12.7 mm, a vystupaniye of a thermal cone of an insulator for a case end face; With - length of a carving of 19 mm, the normal provision of a thermal cone; D-length of a carving of 19 mm, vystupaniye of a thermal cone of an insulator; L-length of a carving of 19 mm, the raised vystupaniye of a thermal cone.
The carvings given about length belong to candles with flat consolidation. In addition “T” (for example, “DT”) - 3 electrodes of weight.

4 — electrode Execution

5 — the Material of the central electrode: without data - a hromonikelevy alloy, With - a copper-nickel alloy, S - silver, З - platinum.

6 — With pomekhopodavlyayushchy resistance.

Applied to BMW of the 5th series of a spark plug are provided in Specifications.

In the course of technical development there can be new types of candles. Consultation about characteristics of candles can be received in specialized workshops.

Condition of candles as characteristic of quality of operation of the engine

On appearance of a candle it is possible to draw a conclusion on work of candles, adjustment of system of injection, quality of a mix and wear of the engine (pistons, piston rings etc.) Address to photographic inserts.

At a vvinchivaniye of candles watch, that they were not drawn, as the sealing washer can be damaged. Do not exceed the moment of an inhaling of 25 Nanometers.


Coal deposits

Symptoms: Availability of soot indicates reenrichment of a fuel and air mix or weak intensity of a spark. Causes ignition admissions, complicates start and results in instability of operation of the engine.
Recommendations: Whether check the air purifier is hammered, whether fuel level in the poplavkovy chamber is not too high, whether the air zaslonka is jammed and whether contacts are not too worn-out. Try to use candles with longer insulator that increases resilience


Symptoms: Zamaslivaniye of a candle is called by wear of maslootrazhatelny caps. Oil gets to the combustion chamber through worn-out directing valves or piston rings. Causes ignition admissions, complicates start and results in instability of operation of the engine.
Recommendations: Perform mechanical recovery works and replace candles.


Symptoms: Porous, white insulator, erosion of electrodes and absence of any deposits. Leads to reduction of service life of a candle.
Recommendations: Whether check there corresponds to requirements of Specifications kalilny number of the established candles, whether the corner of an advancing of ignition is correctly exposed, whether too poor fuel and air mix moves, whether there are no leakages of vacuum of the inlet pipeline and whether valves are jammed. Check as level of a cooler and whether the radiator is corked.

Too early ignition

Symptoms: Electrodes are melted off. The insulator has white color, but can be and is polluted owing to ignition or hit admissions in chambers of combustion of extraneous particles. Can lead to an engine exit out of operation.
Recommendations: Check kalilny number of the established candles, a corner of an advancing of ignition, quality of a mix (whether it is not too grown poor), whether the system of cooling is corked and whether the greasing system normally functions.

Electrocarrying-out luster

Symptoms: The insulator has yellowish color and the polished appearance. Speaks about sudden temperature increase in combustion chambers at sharp acceleration. Usual deposits are thus melted off, taking a form of a varnish covering. Leads to ignition admissions at high speeds of movement.
Recommendations: Replace candles (colder, at preservation of a manner of driving).

Short circuit of electrodes

Symptoms: A waste of products of combustion gets to interelectrode space. Firm deposits accumulate, forming a crossing point between electrodes. Leads to ignition refusal in the cylinder.
Recommendations: Remove deposits from interelectrode space.

Normal state of a candle

Symptoms: Gray-brown color and easy wear of electrodes. Kalilnoye number of candles corresponds to type of the engine and its general condition.
Recommendations: At replacement of candles establish candles of the same type.


Symptoms: Soft brownish color of adjournment on one or both electrodes of a candle. A source of their education are applied additives to oil and/or fuel. Excessive accumulation can lead to isolation of electrodes and cause admissions of ignition and unstable operation of the engine at acceleration.
Recommendations: At fast accumulation of deposits change maslootrazhatelny caps that will prevent oil hit in combustion chambers. Try to replace fuel brand.


Symptoms: A rounding off of electrodes with a small congestion of deposits on the working end. Color normal. Leads to difficulty of start of the engine in cold damp weather and to fuel consumption increase.
Recommendations: Change candles on new, the same type.


Symptoms: Insulators can appear chopped off or burst. Also inaccurate equipment of adjustment of a candle gap can lead to damage of an insulator. Can lead to damage of pistons.


Symptoms: After ignition admissions during a long period of adjournment can be loosened at preservation of working temperature in the combustion chamber. At high speeds of adjournment in flakes come off the piston and stick to a hot insulator, causing ignition admissions.
Recommendations: Replace candles or smooth out and establish into place the old.

Mechanical damages

Symptoms: Can be caused by hit of extraneous materials in the chamber of combustion or arise at piston blow about too long candle. Lead to refusal of functioning of the cylinder and to piston damage.
Recommendations: Remove from the engine extraneous particles and/or replace
As service life of candles usually makes 15 000 km, it is enough to clear of them through each 8000 km of run.