I got my truck back from the shop after they replaced the valve cover gasket and oil is everywhere. They did clean it up a little but not good enough for me. What would be the best degreaser to clean the engine compartment?
I like P21S TAW when things don't need a super-heavy-duty approach. It's not the cheapest stuff though...
The nice thing about TAW is that it's *never* damaged anything IME. Simple Green can cloud certain finishes (e.g., bare aluminum), so be careful if you go that route.
Simple Green or Orange Blast work well. Be careful to put a tarp under your car or park on the street when you use it as any oily greasy drippings might stain your driveway. FWIW, I have had an issue with Simple Green staining aluminum. I now dilute 2:1 with water and it is still very effective.
I use simple green (around 1:4) and old wash mitts to agitate everything... I've got it pretty clean though, so there's no need to go through it all again. It was HORRIBLE when I first did it though (truck had 115k on it when I bought it)... I used SG 1:1 and probably scrubbed stuff that had built up for about 2 hours. Grime was built up in some areas probably about 1/2" thick...
Well, I'd say it's not any crazier than the oh-so-flamable solvents I sometimes use in engine compartments :nixweiss As long as everything's nice and cool it oughta work OK. Solvents like kerosene have been used for stuff like this for a long, long time. I would wonder about its smell and it leaving a residue, but that's all I'd worry about.