hmmm imho, if the one who will wash you engine knows what he is doing, then it is perfectly safe...

pero ako, i really don't have my engine washed by those guys na nasa ordinary carwashes, o maski na sa mga gasoline stations... one error during the wash process and pffffffft......

imho again, the engine does not really need regular washing... what i just do it to brush it (using a paintbrush) every weekend, and wipe some parts, which are not cleaned by the brush... ayus na sya...