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
4. Engine
5. Cooling systems of the engine, heating, ventilation and air conditioning
6. A power supply system and production of the fulfilled gases
6.1. General information and security measures
6.2. Power supply system of petrol engines
6.3. Power supply system of diesel engines
6.4. Systems of release and decrease in toxicity 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


6.1. General information and security measures

Are a part of a power supply system: the fuel tank of a saddle form installed in a back part of the car, a coal absorber of fuel evaporations, fuel-supply lines, the electric fuel pump (on diesel models – in addition fuel pump of high pressure), and also the electronic system of the distributed consecutive injection of fuel operated by an electronic control unit the engine (ECM). Pressure in a power supply system is supported by pressure regulator.

Scheme of a power supply system

1 — the Fuel tank
2 — the Fuel electric pump
3 — the Holder of fastening of the fuel pump
4 — the Soaking-up jet pump
5 — the Valve of restriction of pressure
6 — the Drain safety valve
7 — the Filling ventilating pipeline
8 — the Return gate
9 — the Tube of a jellied mouth
10 — the Cover of a jellied mouth
11 — the Leveling pipeline of the fuel tank
12, 13 — Working ventilating pipelines
14 — the Tank

15 — the Curtain valve
16 — the Tube of removal of vapors
17 — the Returnable fuel-supply line
18 — the Bringing fuel-supply line
19 — the Fuel filter
20 — pressure Regulator
21 — the On-off trilinear valve
22 — the Distributive highway
23 — the Pipeline of supply of external air
24 — the Control unit of the engine
25 — the EVAP Valve
26 — the Soaking-up pipeline
27 — the Coal absorber

The fuel pump is installed in a special holder has in the right part of the fuel tank providing uninterrupted supply of fuel to the pump in all modes and service conditions of the car. Fuel in a holder moves soaking up the jet pump installed in a holder support. The soaking-up jet pump which is built in the leveling pipeline of the fuel tank gives fuel to a holder from the left part of the fuel tank. Both jet pumps are put in action by means of a returnable fuel-supply line, and necessary pressure for operation of the soaking-up jet pumps is regulated by the valve of restriction of pressure. The returnable fuel-supply line is protected by the special valve which is closed if pressure falls at damage or a detachment of a returnable fuel-supply line. Thus the fuel effluence from the fuel tank is prevented, for example, at a turning or inclined position of the car.

The return gate prevents fuel slopping back in a jellied mouth after shutdown of the filling gun.

On petrol models fuel moves fuel э / the pump through the bringing fuel-supply line and the fuel filter to the distributive highway. On models with the M52TU engine fuel moves back in the fuel tank via the regulator of pressure fixed on the distributive highway and a returnable fuel-supply line. On models with the M73 engine return of fuel to the fuel tank is carried out via the on-off trilinear valve, the regulator of pressure and a returnable fuel-supply line. This fuel contour of the engine with return from the distributive highway joins for launch of the engine and remains included less than 1 minute. After this phase the on-off trilinear valve blocks a returnable fuel-supply line from the distributive highway. Along with the help of the same valve the pipeline branch to pressure regulator directly on the fuel filter becomes more active. From the distributive highway fuel at the same time cannot come back. On models the regulator of pressure and the fuel filter unite with the M62TU engine in one knot, the distributive highway has no locking valves and fuel gets directly from knot of the fuel filter / regulator of pressure to the fuel tank again.

On diesel models the fuel electric pump gives to the engine fuel from the fuel tank. For injection in cylinders two types of pumps of the high pressure (TNVD) are used: distributive TNVD (gives fuel directly to a nozzle of each cylinder) and TNVD for the Common Rail system (creates in the distributive highway necessary pressure for all nozzles). In the Common Rail systems between TNVD and the electric fuel pump one more pump – is installed main (M57) or gear (M67), – which at big consumption of fuel supports operation of the fuel pump in the fuel tank.

Level of fuel is measured in each part of the fuel tank by means of the lever sensor. The right sensor is built in fuel supply knot; the left sensor is in knot of the left sensor. The accounting of the received values of electric resistance of the left and right lever sensors gives the actual level of filling of the fuel tank.

Style of driving of the car has significant effect on fuel consumption. Several councils for gasoline economy are given below.

  • After start of the engine at once start even if it occurs on a frost;
  • At a car stop longer, than on 40 with, switch off the engine;
  • Move always on the most admissible high transfer;
  • At the movement on long distances whenever possible support uniform speed. Avoid the movement at high speeds. Without need you do not brake;
  • You do not transport excessive freight on the car;
  • Check air pressure in tires. Do not allow excessive pressure decrease.

Security measure and respect for purity during the work with fuel system

  • Do not work with fuel system near naked flame, do not smoke at the same time and do not turn on heating devices! You keep in readiness the fire extinguisher;
  • Before work with fuel system always disconnect a negative wire from the battery in order to avoid emergence of sparks. Before shutdown of the battery it is necessary to consider codes of malfunctions (see the Head Sistemy of electric equipment of the engine);
  • You monitor normal ventilation of a workplace, – fuel vapors are poisonous;
  • Do not allow hit of gasoline on rubber and leather surfaces since at the same time they can be damaged;
  • The fuel system is under pressure and at its opening fuel can escape, - use goggles. Collect the spilled fuel by rags;
  • Hose connections fasten by means of tape or tightening collars. Tightening collars when dismantling should be replaced tape;
  • Carefully clear connections and the places adjoining to them before opening;
  • Stack the removed components on a pure lining and cover with polyethylene, paper or неворсящейся rags;
  • Close open nipple sockets, for example, suitable caps;
  • Establish only pure details, - take replaceable components from packing just before installation. Do not use the details stored unpacked;
  • Avoid use of compressed air at open fuel system, whenever possible try not to move the car;
  • Do not apply the sealants containing silicone since the particles of silicone which got to the engine do not burn down and can be the reason of failure a lambda probes;
  • Before removal of the fuel tank pump out from it fuel the pump which is specially intended for this purpose;
  • Remember that even the empty fuel tank remains explosive;
  • After installation of components of fuel system start the engine and check tightness of all connections.

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6. A power supply system and production of the fulfilled gases
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6.2. Power supply system of petrol engines