Just wanted to post something I discovered this weekend.
BEFORE DESCRIPTION:
When I acquired the 500E most of the aluminum on the engine block had blackened and had old cosmoline on it. In the process of restoring it I tried Griots Engine Cleaner & Simple Green Automotive, neither changed the appearance even with the assistance of a Nylon Detailing Brush.
My engine bay also has many Zinc Plated (Gold Colored) nuts, bolts and fasteners. These pieces had embedded dirt and some very light dirt buildup as well as old cosmoline. These components were also scrubbed with a Nylon brush and the two cleaners above with no change. The dirt seemed to have etched itself on the surface.
AFTER THE BRASS DETAILING BRUSH:
My friend who has the same car suggested a Brass Detailing Brush and showed me a before and after in his aluminum engine block. So today I tried it and was stunned how well it restored my block, all the dirt buildup brushed away and a quick wipe with a rag brought back the natural finish I wanted.:bow So I started to experiment and tried the brush on some zinc bolts and too my amazement it removed the buildup and left a shiny gold surface.
I used it on my metal brake lines, stainless braided wires and any other metal surfaces which need cleaning up. My engine looks great now and I'm another step closer to being show ready.
Give it a try, just keep it away from plastic and painted surfaces.:xyxthumbs
BEFORE DESCRIPTION:

When I acquired the 500E most of the aluminum on the engine block had blackened and had old cosmoline on it. In the process of restoring it I tried Griots Engine Cleaner & Simple Green Automotive, neither changed the appearance even with the assistance of a Nylon Detailing Brush.
My engine bay also has many Zinc Plated (Gold Colored) nuts, bolts and fasteners. These pieces had embedded dirt and some very light dirt buildup as well as old cosmoline. These components were also scrubbed with a Nylon brush and the two cleaners above with no change. The dirt seemed to have etched itself on the surface.
AFTER THE BRASS DETAILING BRUSH:

My friend who has the same car suggested a Brass Detailing Brush and showed me a before and after in his aluminum engine block. So today I tried it and was stunned how well it restored my block, all the dirt buildup brushed away and a quick wipe with a rag brought back the natural finish I wanted.:bow So I started to experiment and tried the brush on some zinc bolts and too my amazement it removed the buildup and left a shiny gold surface.

Give it a try, just keep it away from plastic and painted surfaces.:xyxthumbs