^ Frederf, I'm not quite sure what message You tried to convey, but You make the procedure more complicated than it really is
. There was indeed a time when priming pump didn't work until pilot started cranking, but this bug was fixed many patches ago. So unless the training mission is glitched in some strange way, a few seconds of prime on stationary engine is enough and she catches right away. Haven't tried this particular mission in ages, but I fly the Mustang on regular basis.
Rhino, just to be sure, you don't use game flight mode do You?