BMW 5 Series E39

since 1996-2001 release

Repair and operation of the car


BMW E39
+ Introduction
+ Maintenance instruction
+ Current leaving and service
+ Engine
- Cooling systems, heating
   - Cooling system
      Check of the cooling system
      Removal, installation and check of the thermostat
      Removal and installation of the fan and coupling of the fan
      Removal and installation of a broad tank
      Removal and installation of a radiator
      Removal and installation of the pump of cooling liquid
   + Heater
   + Air conditioner
+ Power supply system and release
+ Engine electric equipment
+ Manual transmission
+ Automatic transmission
+ Coupling and power shafts
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ Schemes of electric equipment
+ System of onboard diagnostics



Cooling system

The engine is equipped with the circulating cooling system with thermostatic regulation. Until the engine is heated-up, cooling liquid circulates only in a head and the block of cylinders, and at open heating - in the heat exchanger. At increase of temperature of cooling liquid the thermostat opens a big contour of cooling and liquid comes to a radiator, passing it from top to down and is cooled with the air passing through it. The pump of cooling liquid is set in motion by a maple belt of the engine.

On a shaft of the pump of cooling liquid the fan is fixed. The fan provides cooling of a radiator with air. In the fan there is a viscous coupling. At achievement by the air going from a radiator, temperature of 90 °C in the viscous coupling the bimetallic plate works and connects the fan. After that the fan rotates with the speed of the engine and provides the increased heat exchange until temperature of the cooling air does not fall below +60 °C. After that the viscous coupling is switched-off and reduces fan speed.

Thanks to partial connection of the fan the useful power of the engine increases and fuel consumption decreases.

At the warmed engine before opening of a cover of a radiator put on it a thick rag to exclude a burn owing to emission of hot liquid and steam. There is a danger of accident. The cover can be opened only at a temperature of cooling liquid below +90 °C.

Scheme of a contour of the cooling system

1 — a radiator
2 — a broad tank
3 — a heater of salon
4 — the thermostat
5 — the pump of cooling liquid

6 — the block of cylinders
7 — return
8 — giving
9 — heating of a butterfly valve
10 — the heater crane

Chemical heataccumulator

On some models the chemical heataccumulator can be installed. It accumulates warmly cooling liquid, giving it later at start of the cold engine. Thanks to it heating of salon works quicker and loss of heat in the atmosphere is reduced. Time necessary for warming up of salon and the engine is significantly reduced.

The heataccumulator consists of well isolated store in parallel connected to the cooling system of the engine and located around legs of the forward passenger. Depending on need, it takes away or gives to warmly cooling liquid. The stream of cooling liquid, in the course of work, automatically is run by various electromagnetic valves.

The principle of its work is based on use of heat which is released when transforming environmentally friendly hydrochloric mix from liquid state in firm. Similar to warmth of thawing of ice accumulation of warmth of the warmed engine results from liquefaction of hydrochloric mix.

Thus, the thermal accumulator increases traffic safety and comfortableness of the car, without leading to emergence of additional load of the environment.

The accumulator does not demand service as management of it is undertaken by electronics.

Realization of this function is possible only at a temperature of external air not above +15 °C, at the engine which is warmed up up to the working temperature, and also sufficient tension of the accumulator.