Just couldn't let go.....
I just couldn't let go of that last "A" in TAMD41P-A, and wrote Volvo USA. The response is that the name is for Turbocharged "Aspirated" (seems like Aftercooled makes more sense, a note from another source), Marine Diesel, approximately 4 liter, 1 - 1st in series, then P - the 200 horse power calibration, and lastly the final A - first in the 200 hp "P" model, to differentiate it from what could have been additional variation in other models within the TAMD41P category.
You can tell that it's past boating season for me, boat's on the hill for winter maintenance and upfit this winter. Researching all sorts of things on rainy and cold fall days when I'm not raking leaves, looking forward to more fall and winter golf and then spring commissioning!
Build me straight, O Worthy Master,
Stanch and Strong, A Goodly Vessel,
That can laugh at all disaster,
And with wave and whirlwind wrestle. (Longfellow)