
The most common problem with the work of the Mercedes S-Class (W221) is caused by the failure of the pump. To change the pump, do the following:

- Scrolls the nut (2) and removes the seal (3).
- Detach the coolant piping in the wheel arch and remove the heat exchanger and the bachka (1).
- Lift the tank and remove it from rubberized latches (4).
- Pump pump (M5/ 1).
- Disconnect the pump outlet.
- If necessary, I shall seal the gasket (2).
- Put the new pump in reverse.