Water pump
The water pump is installed on the right side of the cylinder block. On cars produced before 1985, the water pump is driven by a V-belt, which simultaneously drives the generator. On cars produced since 1985 - a multi-ribbed belt that rotates other auxiliary engine units.
Alternator drive V-belt
Belt tension is adjusted by moving the alternator.
Belt tension is adjusted automatically by moving the tension roller. On M 102 engines, to ensure the initial tension of the belt, it is necessary to align the adjusting lug with the 7th mark (or from 5th for vehicles without power steering) on the tension roller.
Characteristic | Meaning |
Belt tension when measured with a tool «Krikit», kgf | |
| 50 |
| 40—45 |
Belt type | Continental 9,5 1005La, Dayco 9,5 1000 |
Recommended belts from Bosch (in parentheses is the catalog number) | |
| 9,5x1005 (№ 1.987.947.625) |
| 9,5x940 (№ 1.987.947.600) |
| 9,5x940 (№ 1.987.947.600) |
| 9,5x930 (№ 1.987.947.609) |
Fan
Engine M 102
The fan is driven by the water pump shaft, and it is turned on and off by an electromagnetic clutch controlled by a temperature sensor or a thermodynamic clutch.
Electromagnetic clutch
Characteristic | Meaning |
Temperature,°С | |
| 98—102 |
| 93—98 |
Distance between radiator and fan, mm | 36 |
Radial clearance between fan and guide casing, mm | |
| 25 |
| 20 |
Fan diameter, mm | 380 |
Expansion tank
Characteristic | Meaning |
Pressure in the cooling system, kg/cm2, no more | 1,0—1,2 |
Plug valve opening pressure, kg/cm2 | |
at intake | 0,1 |
at release | |
| |
| 1,0 +0,15 –0,1 / 1,0 +0 –0,2 * |
| 1,2 +0 –0,1 / 1,0 +0 –0,2 * |
* The numerator is for a new valve, the denominator is for a reused valve.
Thermostat
Characteristic | Meaning |
Main valve opening temperature,°C | 87 |
Full opening temperature of the main valve,°С | 102 |
Stroke of the main valve at a temperature of 102°C, not less than, mm | 8 |
Radiator
Radiator aluminum, with horizontal tubes.
Characteristic | Meaning |
brand | Bechr. |
Coolant
Characteristic | Meaning |
Cooling system capacity, l | 8,8 |
Coolant used | mixture of distilled water and antifreeze recommended by Mercedes Benz (at temperatures up to -30°C) |
Replacement frequency | every three years of operation |