[Cloud9sa]

We have had to clean the brushes, etc. on our front cowl motor a couple of times over the years (just engine oil/schmoo that worked its way inside), but had a similar problem to yours with our rear cowl motor that turned out to be a frayed power supply wire -- nothing wrong internally. Sure, it could be worn brushes, etc, but it is worthwhile to check continuity of wiring before yanking out the motor.