No need to prime the oil pump on a 750, gravity feed from the tank will take care of that on startup. I've never primed an oil pump on a 750 and never had a problem.
Kick the engine over a few times or crank the engine over with the kill switch turned off prior to firing it up for the first time, and you should be ok.
BTW the leak stopper valve keeps oil from running down from the tank into the motor when the motor is not running. If it's not working, the tank will drain down into the engine sump over time and the oil level in the tank will be low before startup, then return to normal after startup.
mystic_1