Mercedes S-Class W-140

1991-1999 of release

Repair and operation of the car



Mercedes S-Class
+ Mercedes-Benz cars of the class S (W-140)
+ Operation manual
+ Routine maintenance
+ Engine
- Cooling systems, heating
   Specifications
   - Engine cooling system
      Replacement of cooling liquid - general comments
      Removal and replacement of hoses of the cooling system
      Check of the thermostat
      Removal and installation of the thermostat
      Removal and installation of a radiator of the cooling system - an installation detail
      Removal and installation of the water pump
   + Systems of ventilation, heating and air conditioning
+ Power supply system and release
+ Engine electric equipment
+ Gear shifting box
+ Automatic transmission
+ Coupling
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment


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Engine cooling system

Antifreeze - a security measure from freezing

Do not allow hit of antifreeze on open parts of the body and the painted surfaces of the car.

Immediately wash away casual splashes a plentiful amount of water.

Remember that antifreeze is extremely toxic liquid and its hit in an organism even in small amounts is fraught with the most serious consequences, up to a lethal outcome.

Never leave antifreeze stored in leaky closed container, immediately collect the cooling liquid spilled on a floor.

Remember that the sweetish smell of antifreeze can draw to itself attention of children and animals.

About ways utilization of the fulfilled cooling liquid consult with local authorities, - in many regions of the world special points on different reception of working off are equipped. Do not merge old cooling liquid in the sewerage and on the earth at all!

Recently nontoxical grades of antifreeze are developed, nevertheless, they also had to be utilized in an organized order.

Cooling liquid

The cooling system is all the year round filled with mix of water, antifreeze and rust-preventing agent. It interferes with a rust and corrosion, adjournment of salts and, besides, increases temperature of boiling of cooling liquid. In the cooling system because of expansion of liquid when heating excessive pressure is created that also leads to increase in a boiling point of cooling liquid.

Pressure is limited to the valve located in a cover of a broad tank which opens with a pressure of 1.4 - 1.6 bars.


Faultless functioning of the cooling system of the engine requires the increased temperature of boiling of cooling liquid. At a low temperature of boiling the steam stopper therefore circulation of liquid decreases can be formed and cooling of the engine worsens. Therefore the cooling system all the year round surely has to be filled with mix of water and the listed additives to it.