quick oil changing question
 

I did a search but couldn't find the answer. Do I need to let ALL of the oil come out of the drain pan or is it ok to close it up while there is still some oil leaking out every 10 or so seconds

Kind of a matter of opinion. I think you're fine if it's just slowly dripping out.

Gilly

thanks

This may be the reason that Mercedes has moved to top-loader, suction methods of changing oil rather than gravity oil-plug methods. All Mercedes Benz motors from 1976 on are designed to allow suction oil removal. It's the oficial factory way...

Yeah, i use a suction pump to change oil. It so much easier, faster and convenient.

that black oil (hiding in the oil cooler?)
 

Folks,

As mentioned in another recent post, I was changing the oil on my 87 SDL the other weekend. Looking around while it was draining (from the plug below) I looked at the oil cooler lines. Wondering, I went in and looked at my CD version of the manual. They explicitly say to the effect of " don't worry about the oil sitting in the oil cooler and lines". So no matter how long I would wait, there would be existing oil in the engine anyway. This may be part of the reason for the oil turning black so quickly. I believe it amounts to about a quart.

So all this points back to Larry's mantra... change it often (you know the rest 8^) ). So if a quart was in there, I change at 3K intervals. So it goes another 3K and is diluted in the new 8 quarts. So at the "6K" oil change I would get 8/9's of the old oil out. Not enough old stuff to worry about.

Being pretty new to MB and diesels...do most MB diesels have oil coolers? Does anyone drain their's at O/C time?

Chuck

Yes W123s have oil coolers (pretty sure W126s do also), no, nobody drains them because there is not a plug in them and it is probably not worth the time anyway.

While this is true the more oil you get out the more clean oil that can get in. Yes this is also the reason why it can turn black so quickly.