I don't think putting the vacuum inlet into MMO would suck it in, as the vacuum inlet would actually "blow" if you manually move the motor. There's an "exhaust" port that allows air into the motor, but I think it's under the switching mechanism cover. If you pull that off and then use a dropper to put MMO into the ports there, it would get into the motor.
You can confirm which port will suck MMO in by putting your finger over them when moving the motor manually.
I'd have to dig one of my spare motors out to check that, but I'm pretty sure I'm correct.
