oil film in water

[PT137]

I notice the last few days a oil film around the rear of my 98 sportster. There is oil in the bilge but the pump has not been running. I had to remove and recharge the battery because my kids were in the boat and left the lights on, so I know the pump was not on. I had one of the motors changed and they dumped oil in the fuel tank for break in of the rebuild motor and since then I have notice more oil in the bilge than before, I had this spotless before it when in. Also my morning start I fog the marina but no smoke after running. What is causing the oil around the boat, If I step on the rear platform it appears of if the water calm I see it appers to be coming from under the boat. There is a older bayliner next to me but I see no oil around him

 

[El Toro 33809]

Welcome to the forum. I'm not sure I follow. Is the oil you are speaking if in the engine compartment?