great, thanks. this would explain why cleaning the cooling system helped SeaBreeze with a similar issue. and I did not notice any strong odor and the smoke/steam dissipated in a few feet after the boat. I'll get with cooling system cleaning as the first step.
maybe this also explains the high engine room temperature which looked a bit high to me (around 120F after an hour or two of running at 1700RPM) but the water temperature was always in the green zone so i did not pay much attention to it.*