Dear All:

We bought this 91 300TE six months ago with 127k miles. The car came with some service records and it seemed like it was well taken care of, regular services and oil changes were up to date. We have 135k on it now and everything seems normal for a w124, including the oil leak.

For the past month, I have been noticing a slight rattle when I FIRST start the car up in the morning, especially if I have not driven the car for over 24 hours. The rattle goes away in about 2-3 seconds. I don't hear the rattle for the rest of the day. The car behaves fine, lots of pickup, good gas milage (18 mpg around town, 24 mpg highway). I am worrying about the timing chain. My non MB mechanics said it sounds like it could be the belt on cold mornings. My MB mechanics says he has never seen a timing chain fail in his 25 years working on MB cars.

TIA on any comments.

Paul

A guess...
 

and an uneducated one at that: I've heard some report that the belt tensioner shock absorber can sometimes make a slight rattling noise when it gets worn out. On the m103engine, this little black shock absorber is located on the front of the engine, between the left-front corner of the head and the coolant thermostat housing, extending down at a slight angle out of sight under the belt idler pulley. I think your car has the m104 engine, but I believe it's in a similar location. You can try using something as a stethoscope (like a long screw driver) and listening to it while a helper starts the car first thing in the morning. You've got nothing to loose by checking it out (except watch your fingers and the fan).