Engine sounds like a diesel - M20

[taseal]

What could this be?

perhaps the prev owner put some real thin oil in there so the valvetrain is very very loud and diesel sounding, I'm putting 20w50/10w30 cocktail in there (to get 15w40) valv synth oil (buy one get one free woohoo!)

also would out of adjustment valves do this too? (the diesel sound)

[E34-520iSE]

I think you've hit the nail on the head! That rattle is most probably due to worn or badly adjusted valves - best get them set up ASAP before you snap a cam follower!

ATB,

Shaun M