The drain plug for the W219 OM642 engine block.

[bellox]

Firstly, please provide your opinion on the process of purging the coolant system? Could you kindly provide the location of the drain plug for the engine block on an e320? Finally, if I do not cleanse the system, I am considering disconnecting the lower radiator line and directing a stream of clean water, maybe via the coolant expansion tank or the top radiator hose. Thank you.

[AmericaMonster]

If it is similar to the E350 OM642, the location of the component is in the lower part of the radiator. Rotate and extract slightly to facilitate the drainage of coolant via the stopper.

[bellox]

Thank you for responding. Obtaining the radiator drain plug is not a problem and can be found where you said.

[AmericaMonster]

Indeed. Are you asking whether there is a certain socket on the block? I would infer that the lower coolant pipe is the most likely culprit, based on your description of it.

[bellox]

I am certain that there will be. Otherwise, how can you completely remove all coolant from the system? Or at least 90%.

[PopeyeR]

I cannot definitively confirm its absence, but it has been around two decades since I last saw an automobile equipped with such a feature, leading me to speculate that it is unlikely to be there. It is customary to drain the radiator from the lowest point in the cooling circuit, which is often the bottom. In the case of loud automobiles, this is the standard. After draining, cleanse the radiator using a hose and then use distilled water. Finally, refill the radiator.