I use a 2700 PSI pressure washer. I would use a steam cleaner if it were more available. I don't like getting wet and you get chunks of grease all over you, butit's worth it if you are going to work on them. Keep in mind that it may leak or weep oil worse when you are done, so you might want to be prepared to replace some gaskets. Stay away from the hoses and belts. The water pressure can ruin them quickly.
