[KevinW]

I noticed my inlet manifold has started to develop a poor surface finish - I think the aluminium silver grey surface has started to get dusty, but there are also faint gold-like patches starting to emerge. Also saw this on my old Rover/Buick V8 years ago, but ignored it.

As the carb is off the car at the moment, is there an easy clean up I can do in-situ? I don't really want to remove the manifold.