Patina...

[66cayne]

Originally Posted by Lee Stewart

Oven cleaner is an acidic substance that removes baked-on grease and grime from ovens. The active ingredient in most oven cleaners is sodium hydroxide, with a pH of 13. This means it is highly alkaline and can cause burns if it comes into contact with the skin.

yes, its great for engine compartment cleaning prior to repainting. Takes the grease and grime off right down to the metal (just be sure to cover and tape off the cars paint to protect it)