Filling and bleeding the cooling system (Mercedes-Benz E-Class W123)

1. Check the tightness of the drain plugs and set the air intake control switch to the maximum warm air supply position.

2. Slowly fill the coolant to the "Max" mark on the expansion tank.

3. Start and warm up the engine (periodically press the accelerator pedal lightly to speed up warming up).

4. When the coolant temperature reaches 60-70°C, tighten the expansion tank cap.

5. Stop the engine, check the fluid level. If the level is below normal, add coolant.