Agreed. I took Dave's concerns not as a diagnosis of cause but just noting an irregularity. Since then I have run both engines many times and not seen a repeat of the survey puff and sheen...so I think I am ok. Porter will need to look at the recent run time history of the boat to see if this is just an artifact of an unused vessel that will go away with more frequent activity.
Oh, and Mark, thank you for reccomending Dave. He was great.
Vent de Soleil SM37