to answer everyone

the belt was off and I was using a mechanics stethescope touching various assemblies and bolt heads - the noise is loudest at the lifting eye.

I disabled the pump by unplugging it

still the same noise.

The engine counter balancer is placed in the valley of the engine and so are two guide rails for the timing chain pointing towards the heads. Something there is causing this noise to emit and is amplified by the lifting eye (my assumption)

I used chevron delo 5w40 as the first oil in this engine and fleece filter - over time it quietened the overall sound of the engine and became really really dirty. The oil filter previously installed was not pushed all the way on the stalk leaving some area of the central tube uncovered - so technically previous to my oil change the engine was running with no oil filter.

Any bets that would cause rapid chain wear - I think yes, but why has the engine not popped up a timing error?

Me thinks a video is to be made...

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)