Mercedes-Benz W211 E-Class Draining Filling Cooling System

Engine coolant is the working fluid for the cooling system, which controls the operational temperature of the engine. Each combustion event inside your engine creates a lot of heat and the engine needs to be at a certain temperature to operate efficiently. Engine coolant maintains about the same temperature year round, regardless of ambient temperature.

Your Mercedes-Benz will lose a little bit of coolant here and there over time due to evaporation from the reservoir. However, a significant loss of coolant over a very short period of time almost certainly signifies a leak in the system. Sometimes a leak can be seen when you park the car overnight. Often the coolant leaks out and then evaporates while you're driving, leaving no tell-tale mark of coolant on the pavement. If you suspect a coolant leak, visually inspect all of the hoses, the water pump, the reservoir, and the radiator for seepage or the 'weeping' of coolant out of seams and gaskets. Check the seal on the radiator cap. Check that the radiator cap is fastened securely - the way the Mercedes-Benz radiator cap is designed makes it easy to make the simple, yet deadly mistake of leaving the cap cocked - allowing coolant to leak out when the engine is running. If you suspect a leak that you cannot see, a pressure test from can verify the integrity of your system. See our tech article on cooling system leak testing.

Draining and filling your cooling system is a maintenance requirement as well as being part of many repairs. Be careful when working with coolant. It is poisonous and especially dangerous for pets. Clean all spills immediately and rinse the area with water.

Have about two gallons of 50/50 mixed coolant on hand for the service.

Read the Full Article:
https://www.pelicanparts.com/techarti...

Time: 1 hours
Tab: $60
Tools: Flathead and Phillips screwdrivers:https://www.pelicanparts.com/Mercedes..., 8mm socket:https://www.pelicanparts.com/Mercedes...
Applicable Models: Mercedes-Benz W211 (2003-09):https://www.pelicanparts.com/catalog/...
Parts Required: Engine coolant:https://www.pelicanparts.com/catalog/...
Hot Tip: Work with a cool engine
Performance Gain: Cooling system parts lifespan increased
Complementary Modification: Replace hoses:https://www.pelicanparts.com/techarti...