Question about oil leak from top of engine
 

I recently bought a 2007 s550 w221 and I noticed that it drips/leaks oil. After checking it out it seems it is coming from the oil separator and cam shaft caps. Is there a procedure on how to replace these? Also if I neglect it for a month or 2 would that be an issue? Would that cause damage to the engine?

I would guess (not having seen the engine) that your leak is likely coming from the oil cooler/filter housing.

When I changed my spark plugs I found the #1 cylinder plug hole to have significant oil in it. The factory procedure for locating leakes mentions several times that due to air currents under the hood can make leak detection difficult and I agree! It wasn't until after I degreased the engine that I found the leaks to be coming from the oil cooler housing gasket, not uncommon for the M272/273 engines at 100k+ miles. Because it was $80, I bought the whole new filter/cooler housing from the dealer and it included the gasket between the housing and the engine block.

Remove the oil separator (part # 2720100631) and detach hose, intercept the engine oil that flows out with an absorbent rag. Expansion plugs (0009985590 & 0009985690) simple pull and replace.


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Could be the oil cooler (seal between that square aluminum part and a housing)
or a seal between the housing and the engine