VANOS hub spring washer orientation, which way?

[sapote]

TIS says to have the spring small dia pointing (touching) to the supporting ring 3, but why?
Also why the supporting has the deep grooves cut on both sides of the retaining lugs (which prevent it from rotating inside the hub)? They could make the lugs without cutting the grooves on the ring.

[bmwfnatic]

The S62 up to 09/2001 which shares the “A” spring set with the S54 has the same schematic.



The S62 after 09/2001 which has the “B” spring set commonly referred to as the S62 upgrade, has a different schematic, basically flipping the spring around.

[sapote]

The S62 after 09/2001 which has the “B” spring set commonly referred to as the S62 upgrade, has a different schematic, basically flipping the spring around.

I didn't see pic of the S62 assembly drawing until you posted it. It makes more sense to have the larger end pointing to the supporting ring as it provides more bearing surface for the spring compared to the other way around -- the spring ID is about the same as the ring ID and so this is not much of a bearing surface.

[Slideways]

The S62 up to 09/2001 which shares the “A” spring set with the S54 has the same schematic.



The S62 after 09/2001 which has the “B” spring set commonly referred to as the S62 upgrade, has a different schematic, basically flipping the spring around.

Did you swap to the "B" spring? Considering swapping back to the "A" version.