Mercedes of the S-class W202

1993-2000 of release

Repair and operation of the car

Mercedes W202
+ 1.2. General information
+ 2. Maintenance
+ 3. Engines
+ 4. Lubrication system
- 5. Cooling system
   - 5.2. Cooling liquid
      5.2.2. Diesel engine
      5.2.3. Cars with the conditioner
   5.3. Antifreeze for a radiator
   5.4. Temperature regulator of cooling liquid (thermostat)
   5.5. Check of the cooling system
   5.6. Hydraulic coupling of the fan
   5.7. Pump of system of liquid cooling
   5.8. Radiator
   5.9. Fan casing
   5.10. Diagnostics of malfunctions of the cooling system
   5.11. Diagnostics of malfunctions of system of indication of level of liquid
   5.12. Engine overheat
+ 6. Heating, ventilation
+ 7. System of ignition
+ 8. Fuel system
+ 9. Transmission
+ 10. Running gear
+ 11. Steering
+ 12. Brake system
+ 13. Body
+ 14. Electric equipment
+ 14.2. Electrical circuitries

5.2. Cooling liquid

5.2.1. Petrol engines


1. Block of cylinders of the engine
2. Head of the block of cylinders
3. Pump of system of liquid cooling
4. Regulator of cooling liquid (thermostat)
And – the mode of circulation of cooling liquid on a small contour. Cooling liquid circulates only in the engine at its temperature below 87 °C
In – the mixed mode. At temperature of cooling liquid within 87–102 °C the regulator of cooling liquid is partially open. The last proceeds also through a radiator
With – the cooling mode. At a temperature of cooling liquid above 102 °C its regulator is completely open. All cooling liquid proceeds through a radiator
5. Top pipeline of cooling liquid
6. A radiator with a horizontal stream of cooling liquid
7. Lower pipeline of cooling liquid
8. Oil heater
10. Compensation tank
11. A silicate reserve for prevention of corrosion of aluminum alloys
12. Drain tank
13. The line for removal of air
14. Gas station line
15. Heat exchanger of system of heating
16. Heating supply
17. Withdrawal of heating on the right
18. Withdrawal of heating at the left

Within servicing cooling liquid should be replaced each 3 years. If at repair of a head of the block of cylinders laying of a head of the block, a radiator, the heat exchanger or the engine were replaced, then in each case replace cooling liquid. It is necessary because on the new details made of light alloy in the period of a running in anticorrosive products of disintegration are besieged and form a strong anticorrosive layer. At the cooling liquid of these anticorrosive products of disintegration which was in the use, as a rule, contains insufficiently in order that on new details to form a necessary protective layer.

If within carrying out other repair work cooling liquid merges, reuse it.


Cooling liquid is poisonous, and it cannot just be poured out or mixed with household garbage, and it is necessary to merge to special places.

1. Disconnect a wire of mass of the rechargeable battery.

At the same time the anticreeping code of radio is erased.

2. Turn a cover on a compensation tank to the left until it is recorded and excessive pressure does not disappear from the cooling system. Then further turn a cover and completely remove it.

If the engine hot, before removal of a cover lay around it a thick rag to avoid burns because of the emitted hot cooling liquid or its vapors. Uncover only at temperatures of liquid below 90 °C.

3. Remove the lower cover of a motor compartment.
4. Get on the drain union of a radiator (shooter) a hose with an internal diameter of 12 mm.
5. Install a pure reception vessel under a radiator. Enter a hose into a reception vessel and open a carving stopper of a drain opening (3).


1. Get on a stopper of a drain opening (4) on the block of cylinders of the engine a hose with an internal diameter of 12 mm.
2. Install a pure reception vessel under the engine, enter into it a hose and only weaken a carving stopper of a drain opening, without unscrewing it completely.
3. Completely merge cooling liquid.
4. Tighten a carving stopper of a drain opening on the block of cylinders of the engine with m 30 N.' moment.
5. Screw in a carving stopper of a drain opening on a radiator with m from 1,5 to 2 N.' moment (manually).
6. If it is got, remove a drain hose.
7. Establish the lower cover of a motor compartment.

Gas station

1. Check the content of antifreeze in cooling liquid.
2. Fill in cooling liquid to a mark (shooter) through a bulk branch pipe of a compensation tank (2). At cars without separate compensation tank – to a mark in a bulk branch pipe, in case of a black top part of a tank – prior to the beginning of a black part.
3. Connect a weight wire to the rechargeable battery.
4. Leave to get warm the engine idling until the regulator of thermostabilization of cooling liquid opens (temperature of cooling liquid about 100 °C). At the same time establish heating at full capacity and breakthroughs press an accelerator pedal.

At a temperature of cooling liquid from 60 to 70 °C close a compensation tank.

5. Check tightness of hose connections of the cooling system, and also carving traffic jams of drain openings and the pump of system of liquid cooling.
6. Expose time on hours.
7. Enter an anticreeping code of radio.