[Kracka]

A lot of those engine degreasers in a can should be avoided, they will fade/dry rubber hoses. You also should not use Simple Green since it is corrosive to aluminum. I suppose you could use it, but its best to rinse the engine first so there is some water to dillute the SG a bit. Meguiar's makes a product called Safe D-Greaser which works very well for engine bays, but it is tough to find so you may have to order it online.