BMW 7_aya the E38 series from 1994 to 2002
1. Introduction
2. Governing bodies and methods of operation
3. Settings and routine maintenance of the car
3.1. General information
3.2. General information about settings and adjustments
3.3. Schedule of routine maintenance
3.4. Check of levels of liquids, control of leaks
3.5. Check of a state and replacement of hoses and tubes in a motive compartment, localization of leaks
3.6. Replacement of motive oil and oil filter
3.7. Clearing and replacement of the fuel filter
3.8. Check of the brake system and coupling
3.9. Check of a condition of system of production of the fulfilled gases
3.10. Check of a condition of components of a suspension bracket and steering
3.11. Check of a condition of protective covers of CV JOINTS of power shafts
3.12. Replacement of the AT gearbox oil
3.13. Replacement of brake fluid and pumping of the brake system
3.14. Replacement of spark plugs
3.15. Replacement of the saloon filter (system of ventilation)
3.16. Replacement of the filtering air cleaner element
3.17. Replacement of cooling liquid
3.18. Check of a condition of tires and pressure of their rating
3.19. Check of a condition of the battery and care of it
3.20. Check of a condition of a belt of the drive of auxiliary units
3.21. Check of a condition of brushes of screen wipers and adjustment of nozzles of washers
3.22. Replacement of oil of the main transfer
3.23. Check of thickness of the conducted clutch plate
4. Engine
5. Cooling systems of the engine, heating, ventilation and air conditioning
6. A power supply system and production of the fulfilled gases
7. Systems of electric equipment of the engine
8. Manual box of gear shifting and coupling
9. Automatic transmission
10. Cardan and power shafts, reducer, differential and stupichny assemblies
11. Brake system
12. Suspension bracket and steering
13. Body
14. Onboard electric equipment
15. Schemes of electric equipment




3-14-zamena-svechejj-zazhiganiya.html

3.14. Replacement of spark plugs

Spark plugs should be replaced only on cold or slightly warm engine. The reversing of candles on the hot engine can entail damage of a carving to a head of cylinders.


 PERFORMANCE ORDER

  1. Switch off ignition and remove the corresponding coil of ignition (see the Head Sistemy of electric equipment of the engine).
  2. Turn out a spark plug by means of a long face key, trying not to incline it.
  3. Estimate a condition of spark plugs (see the illustrations Condition of Spark Plugs). If necessary correct possible malfunctions about which it is possible to judge by a condition of candles. Coal deposits on electrodes can be removed with compressed air under pressure, do not use a wire brush for this purpose. Check and adjustment of an interelectrode gap in intervals between replacement of candles is not required.
  4. Establish new spark plugs and tighten them with the required effort.
  5. Install ignition coils.

Condition of spark plugs

Coal deposits

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

Oiling

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

Overheat

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

Too early ignition

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

Electroconductive luster

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

Short circuit of electrodes

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

Normal state of a candle

Symptoms: Gray-brown color and easy wear of electrodes. The Kalilny number of candles corresponds to type of the engine and its general state.
Recommendations: When replacing candles establish candles of the same type.

Peploobrazovaniye

Symptoms: Soft deposits of brownish color on one or both electrodes of a candle. A source of their education are the 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 bystry accumulation of deposits change maslootrazhatelny caps that will prevent hit of oil in combustion chambers. Try to replace fuel brand.

Wear

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

Detonation

Symptoms: Insulators can be chopped off or burst. Also inaccurate technology of adjustment of a candle gap can lead to damage of the insulator. Can lead to damage of pistons.

Zabryzgivaniye

Symptoms: After admissions of ignition 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 the hot isolation center, causing admissions of ignition.
Recommendations: Replace candles or smooth out and establish into place old.

Mechanical damages

Symptoms: Can be caused by hit of foreign materials in the combustion chamber or arise at blow of the piston about too long candle. Lead to refusal of functioning of the cylinder and to damage of the piston.
Recommendations: Remove foreign particles from the engine and/or replace sveya.


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3.15. Replacement of the saloon filter (system of ventilation)