How to remove substance from engine?

I know there was a name for the substance that is found on older E30 BMW engines. It appears to look as if oil baked on the valve cover. What is it called and how do you remove it? Originally thought it was called cosmos????? Thanks

It is a frequent issue in wood working circles, wood working machines are shipped with cosmoline as a rust inhibitor. They seem to like WD-40, mineral spirits and laquer thinner. You can do a search for "remove cosmoline tablesaw" you will get lots of hits.

Thanks for the response and ideas. Now the work begins. I knew that before the E30's were transported to the US, BMW had the engines sprayed to prevent the salt from pitting. Now I know how to remove this.

Thanks for the feedback. I will look for products now that I know the correct name of the substance.

www.cosmolinedirect.com has a remover that they sell. $44 a quart though so other options may be worth a try first.