If it was brought down at hull speed (1000 rpm or less) then that would be a cause for smoke. Have the fuel filters been changed lately? How old is the fuel?
Fuel filters are good. She is only carrying about 200 gals of unknown age fuel. No sign of water or gunk. Fresh fuel and a hard run could be the answer. We shall see. Thanks again for suggestions.
Can we get a color bar next to the smoke at idle (fast idle), under way, and heavy loaded? Blue, white, grey, black, steam dissipating quickly, smoke that burns your eyes. I have a feeling of blown injector tips but really need more finite details. After the loaded run, does the heavy (any) smoke return idling back to the dock?
I'm thinking fuel too but I think they would've blown through most of it. If fuel filters are all clean and air filters, I'm leaning towards RCRAPPS thinking of injectors. Did they do an injector cut out test with the laptop to make sure there aren't any injectors that are way off?
I am no longer in the Seattle area but have been in touch with the MTU shop. They are continuing to analyze data and will do additional testing. I will post results when I next hear from them. Thank you all for you input and suggestions. The experience on this site is invaluable.
Also air and water temps are pretty cold in Seattle area right now, perhaps it's just the colder temps.....I don't know.
For the last cold start, we had block heaters on for a couple of days. Amazingly, no smoke. It may be these guys just don't like being started in fairly cold conditions (around 30 degrees F). So far, everything on the engines is checking out ok.
30F I think ANY diesel is going to smoke a lot at that temperature and it's not recommended to even start a diesel under 60F without block heaters on. A lot of old mechanical diesels won't even start under 50F.....
Full mechanical survey completed by authorized MTU shop on both motors. It was simply a matter of using the block heaters. Once we started using them as recommended by the MTU shop, the smoking issue has been resolved. Thank you for all of those who offered there opinions and shared their experience.