Mercedes S-Class W-140

1991-1999 of release

Repair and car operation

Mercedes S-Class
+ Mercedes-Benz Cars of a class S (W-140)
+ Operation manual
+ Routine maintenance
+ Engine
- Systems of cooling, heating
   Specifications
   + System of cooling of the engine
   + Systems of ventilation, heating and air conditioning
+ Power supply system and release
+ engine Electric equipment
+ gear shifting Box
+ Avtomaticheckaya transmission
+ Coupling
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment

Systems of cooling, heating

General information

System of cooling of the engine

All models of cars considered in the real Management are equipped with system of cooling of the engine working at superfluous pressure with thermostatic management of circulation of working liquid. The water pump is fixed on the block of the engine and provides pumping of cooling liquid through an okhladitelny path of the last. The stream of liquid washes regions of an arrangement of each of cylinders in the block then goes to a back part of the engine. Laid in molding of the block and a head of cylinders okhladitelny channels provide intensive cooling of inlet and final ports, areas of installation of spark plugs and directing plugs of final valves.

General scheme of functioning of system of cooling


1 — the Broad tank 2 — the Cover 3 — the Built-in silikogelevy tank 4 — the Intaking branch pipe 5 — the Radiator 6 — the Thermostat 7 — the Ventilating tube 8 — the Stream from the engine to a radiator 9 — the Stream from a radiator to the engine 10 — the Pump of system of cooling	11 — the Oil radiator 12 — the Block of cylinders 13 — the Head of the block of cylinders 14 — the Forcing pipeline of a heater 15 — the Heater of stekloomyvatel 16 — a heater Radiator 17 — the Valve of a double pulsation 18 — the Circulating pump 19 — the Returnable tube of a heater

From the moment of engine start the system of cooling passes through three modes of functioning: at the first stage while the temperature of cooling liquid did not rise above a certain value, it circulates on a small circle from which working contour the radiator is excluded. In process of further warming up of liquid the tarelchaty valve entering into a path of system of the voskozapolnenny thermostat opens and the radiator is connected to a contour of circulation. Further, on reaching temperature of cooling liquid of the next control value, works the thermosensitive sensor switch providing activation of the fan of system of cooling, forced which the additional air stream considerably increases efficiency of functioning of the heat exchanger of a radiator.

The system of cooling has a tight design and is densely closed by a cover of the radiator, capable to maintain a certain superfluous pressure that provides increase of a boiling point of cooling liquid and, respectively, efficiency of a heat-conducting path through a radiator. At excess by internal pressure in system of some certain value, there is an overflowing of excess of cooling liquid on a connecting (perelivny) tube in a broad tank. In process of system cooling liquid automatically comes back from a tank to a radiator.

Dolivaniye of cooling liquid in system is made through a mouth of a broad tank (see. Head Routine maintenance) which at the same time acts also as a receiver accumulating in forced out from a radiator excess of liquid.

In view of the listed features of a design, such system of cooling received the name closed as in it any functional losses of a working body are excluded.

Heating and ventilation system

The system of heating consists of fans and the heat exchangers located in blocks of forward and back parts of salon. Hot cooling liquid passes through heat exchangers. When moving the handle of management by modes of the heater, located on the control panel (for more details see. Comfort of Head the Operation manual) open valves and hot air starts to arrive in car salon. If to turn on the heater fan, air will move in salon compulsorily.

External air before getting to salon, passes through the filter (address to Head Routine maintenance). The main share of particles of a dust will settle in the filter. It is necessary to observe periodicity of replacement of the filter. The filter blocked by a dust will limit supply of air in salon that will lead to an air stagnation in salon.

Distribution of streams of air of system of ventilation is carried out with the help a zaslonok. The air circulation mode is provided. Zaslonki cope with the help of servo-drivers.

Independent heater

The independent heater providing possibility of independent warming up of the engine and salon of the car on a signal of the timer or from the DU panel can enter into a regular complete set of separate models. The principle of functioning of an independent heater is considered in the Section the Independent heater of Head the Operation manual.