Hi just got my motor rebuild and I've done about 2 hours of riding ruining it in but today when I took it out I looked behind me after starting it and then turning off I looked back and the water was like rainbow like oil on the surface so I took the ski home and flushed it I noticed oily water coming from my exhaust and also from where you flush it at the back it was milky coloured my mate thinks it's the oil cooler what are your thoughts Tia