N57 timing chain?

[JonDerz]

I gambled on a high mileage 435d 2014 at the auction last week on 180k

The car actually drives well, however on cold start there’s a chain like clatter that appears when the engine is revved, and gets worse with higher revs. But there is zero clatter on cold start up and cold idle, only when revved. It goes completely when warm. Surely its chain stretch that I’m assuming is audible when load is placed on the engine but I’m not sure why there’s no sound when starting up. Thoughts?

https://youtube.com/shorts/KP0YJoRkSWE?si=zLD3VXti...

Edited by JonDerz on Sunday 3rd November 16:12

[rassi]

When cold, the chain is slightly shorter, and the chain tensioner maybe tighter, whereas warmed up everything is stretched a bit?

[danb79]

JonDerz said:

I gambled on a high mileage 435d 2014 at the auction last week on 180k

The car actually drives well, however on cold start there’s a chain like clatter that appears when the engine is revved, and gets worse with higher revs. But there is zero clatter on cold start up and cold idle, only when revved. It goes completely when warm. Surely its chain stretch that I’m assuming is audible when load is placed on the engine but I’m not sure why there’s no sound when starting up. Thoughts?

https://youtube.com/shorts/KP0YJoRkSWE?si=zLD3VXti...

Edited by JonDerz on Sunday 3rd November 16:12

Have a read here: https://f30.bimmerpost.com/forums/showthread.php?t...

[JonDerz]

rassi said:

When cold, the chain is slightly shorter, and the chain tensioner maybe tighter, whereas warmed up everything is stretched a bit?

Wouldn’t that mean it’s noisy when warm if it’s stretched? There’s no noise when the engine is warm, or at cold idle, only revved when cold

[rassi]

JonDerz said:

Wouldn’t that mean it’s noisy when warm if it’s stretched? There’s no noise when the engine is warm, or at cold idle, only revved when cold

Indeed, I read it too quickly, as if the noise was only there when warm. Still, the tensioner could be bad, and the chain ok.

[DS900]

Any 435d is likely to have a had a reasonably hard life, especially across 180k. If it were me I’d look at having the chain replaced at some point anyway and you’ll doubtless have plenty of life left in it. Any evidence of the chain having been done?