Just an FYI since its been asked (and answered)...but some are still curious as to tell how far to fill the engine coolant in the filler neck. I'm going to assume that the S63 and the N63TU (engine coolant) filler neck and reservoir are similar...since neither has any visible indicator to tell how full the reservoir is. The BMW TIS states for the n63TU that the coolant level should come up to between 110mm-160mm (4"-6") below the top of the fill neck. If you look around your garage/home...you can quickly find something to use as a measuring tool...mark off the correct fill length and use it to stick down into the fill neck (ie, straw, chop stick, ruler, old cardboard box top). And if you do take one of your wife's cooking tools like a wood spoon handle or her turkey baster...remember to just buy her a new one and keep the one you took in the garage...woulnd't want to make the family sick from using a tool that has coolant residue left on it.
