What appears to be a water and oil mix, drips down from between prop and housing, after a few minutes of running. I have replaced the prop seal, ran motor, but it did not solve the problem. I own a 15 hp 1991 evenrude. I'm told by a dealer I can run engine as long as the lower unit has clear gear oil in it. A repair shop said they feel it's some kind of winter storage condensation and won't harm engine when running and that it will dissapate. I am going on a long fishing trip and don't want to find out that this was bad information.