How to top up engine oil
I think you mean oil top off, to do this simply check the oil dipstick see how low it is, remove oil fill cap on the engine and add until it reaches the full mark then replace the oil cap, make sure you use the recommended engine oil. I have never heard of an oil casket, but there are different kinds of gaskets that are oil related.
Man, if you don't know how to add oil, I would advise you to never open the hood on that car- just take it to your friendly Mercedes mechanic for service-
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