Risk of fresh water flushing ?
 

If i run the hose into my engines before starting can i possibly get water backed up into my exhaust and possibly get water in my oil.....have a naturally aspirated pair of 650's w cmi headers. and i suddenly have milky oil in both engines, starting to look tonight but just changed old oil ( it was clean ) and only changes is flushing daily and lowering boat on an angle with a hydro hoist....Any Feed back ?? doubt i have 2 leaks in motors