engine rattle on startup,

[ian6]

Newbie here, good morning all.
Just bought a CLC 180K in black, 47000 mls, Noticing a rattle on start-up that disappears after a very short time as if the oil has reached the top of the engine, Is this normal? or am I looking at cam chain fail, another point to mention oil level appears to be overfilled, is this detrimental?. Car still under traders warranty so need to get this addressed asap. Regards

 

[Giantvanman]

Overfilling with oil can cause all sorts of problems, none of them good. The oil should be checked on MBs with engine warm; you can get an online owner's manual from here Owners Manual: A Go-To Source for Information on your Vehicle | Mercedes-Benz which describes the way to do it…I don't know if your model has the oil check facility in the dashboard menus. A rattle on start up MIGHT be the chain tensioner getting its act together, as it were, but probably better wait for someone with better knowledge than me.

EDIT: Not wanting to send you into a spiral of panic but years ago, it was common for the less scrupulous sellers to drastically overfill with oil to mask rattles and problems long enough to get it out of the door, hence the 'urgency' to check the level correctly.

 

[ian6]

thanks for the rapid reply, already came to the same conclusion as your good self concerning the oil overfill. The engine purrs after initial start and goes like the proverbial off a shovel, I was just a little concerned about the intensity of the said rattle.

 

[Giantvanman]

I found this previous thread (there are probably others) http://www.mbclub.co.uk/forums/engine/185581-c180-kompressor-2006-replace-timing-chain.html
The oil overfill and a rattle would lead me to believe someone is either hopelessly incompetent (a lot of that going around these days) or someone is trying to hide a possible problem (cam chain and or tensioner) by overfilling with oil.
Where in the country are you as there are some really good independent specialists you could ask to have a look or you could post a link a recording of the noise.

 

[martyz]

If the oil level is high(over filled) don't drive it until it has been drained,it will cause
high oil pressure and blow gaskets.

 

[ian6]

Thanks all for the very informative posts, will take all advice and act accordingly. Regards Ian
PS will keep you informed of the outcome