what's leaking? wet and oily under intake manifold

[Nimimbu]

Hi, I’m getting ready to walnut blast my 35d and noticed wet oil and long term build up when I removed the intake manifold. See pics. Any thoughts on what might be leaking? Maybe the gasket on the tangential port? (Which will be getting replaced)

Thanks for any ideas

[Gee-Dog]

It's likely coming out of the bottom of the swirl flaps. I've just replaced my swirl flaps with aluminium bungs, hoping to stop the oil leaks.

[Nimimbu]

Thanks gee-dog. May have to blank those swirl flaps in the future.