Re: Basic Diesel Course
Check your local community college, they sometimes offer a tech oriented curriculum that is very very transportable to boats.
Bearing in mind some of the input above - I sort of agree, a course on yanmar's is nice if you own a yanmar. Look around for a good, small time diesel mechanic and get him/her to give you a personal lesson, even at 100 a hour you get a good walkthrough on YOUR engine, as installed, on your boat.
I've done that on every boat I've owned and never regretted it.
Be very clear with contracting that out - make sure they KNOW you expect them to show and tell.
Lessons learned are opportunities earned.