okay i just got a new boat and we ran it on muffs for a feww minutes and when we did i notice there is like a sludge coming out of the prop.When i took it out to run it thinking maybe it was unburned oil it seemed ok but when i pulled it out of the water i now see this same thing coming from between the lower unit and the shaft i guess is what its called.There is like a weep hole there and its coming from that hole any help would e great i dont want to ruin my engine thanks guys.