Not to sure this is the place to post this, but it is the closest place I can find to put it. My son had an exhaust leak while I was away at work. Well needless to say he didn't fix it. It caused the motor to get smutted up pretty bad with exhaust soot. What is the best way to get this off? I really need a spray on and wash off type stuff. Reason being, I am not to sure I can whipe and scrub every small area on the motor.