Cleaning Engine
 

I bought some engine degreaser (engine brite gel) and I'm aware that there are certain areas which should not be used with the degreaser chemical. What should I NOT use this on? Also if it is obvious to you, it may not be obvious to me. I've never done this before.

Some degreasers contain sodium hydroxide & alkaline salts - even diluted they will attack paintwork in the engine compartment - ask me how I know after cleaning down my wifes Volvo engine. The metalic red paint wiped off with a cleaning rag after I sprayed on the degreaser, leaving just the undercoat i gray!!!
I was not popular with her.....

Yikes! I can imagine. So is there even any painted surfaces in the engine compartment? I didn't think there was.

Use simple green.

...or use S100 engine cleaner.

As said previously, the product I already purchased is called Engine Brite Gel and is made by Gunk. The ingredients are as follows:

Petroleum Base Oil
Hydrocarbon Fluid
Petroleum Naphtha
Orange Oil
2-Butoxy Ethanol Surfactand Blend
Carbon Dioxide

It's not like I plan on using this on the paint of my vehicle so I don't know why I should worry about it eating paint, nonetheless it doesn't contain any of the aforementioned chemicals that are known to do this. Back to my original question though, where should I not use this substance (electrical housings, air filter, etc...). I don't know what is ok and not ok to use this on in the compartment.

It's tempting to scrub it all up, but it really doesn't do much good. It's not like your friends will see the engine anyway!!! I'd use simple green or windex or some other light duty spray and wipe method on what you can reach with a rag and be done with it. Your engine will remain happy.
Old cars lacking all the fancy electronics could be hosed easily and come out nice. But these engines are another story.

engine brite
 

i think i can relate to a clean engine, just so tempting to really degrease and just hose it off..recently, my godson technician was here helping me out with another car, when we opened up my engine bay on my '04S, and his immediate reply was.. you're not treating this up with your Gunk degreaser..i hope? so i ended up just wiping it off with a damp towel.
in your case, unless your whole engine compartment is really dirty and greasy, to answer your question i guess the obvious electrical components are the areas to avoid .. good luck we to hear what happens next?

Easy way
 

Just use some of that old Armorall you have in the garage. Mostly dust and it will wipe right off.

So today I finally got around to cleaning up my engine. I used Engine Brite Gel by Gunk. It was done rather sloppy. I simply sprayed the chemical on the top of everything. I didn't do it liberally, but as much as I felt was necessary. I then took a rag and wiped down as much as I can. There wasn't much electrical that I worried about (I didn't cover anything up) and I didn't spray that much where the air intake is. I then hosed everything down being careful not to get too much water in that area. Then took it for a ride so it could dry off. Here are before and after pics. You can notice that there are areas of dust that I didn't get to. Just mainly the top and sides is what I cleaned. I will maybe get to the other areas another day.

http://i498.photobucket.com/albums/r...v/DSCN0415.jpg
http://i498.photobucket.com/albums/r...DSCN0416-1.jpg
http://i498.photobucket.com/albums/r...v/DSCN0419.jpg
http://i498.photobucket.com/albums/r...v/DSCN0417.jpg
http://i498.photobucket.com/albums/r...v/DSCN0421.jpg
http://i498.photobucket.com/albums/r...v/DSCN0418.jpg
http://i498.photobucket.com/albums/r...v/DSCN0422.jpg