Recently posted a forum question on my merc 470 3.7. Topic was (merc 470 oil in sump) but today i was asked "did you check the flapper in the exhaust??? the answer was no. I did not take anything apart yet. The problem is water in the oil sump and all cyl. are showing good on compression and it starts hard but runs smooth when going. So the question today to me was did you check the flapper? So now I ask the forum....can a bad flapper add water to the crankcase and turn my oil to milk?Please chime in and help
