Re: 1972 9.5hp model 9R-72M runs rough mid range
Welcome to iboats.
It sounds like the ignition is not advancing properly.
Most of the older smaller outboards there is a cam that a wheel rides across as you twist the throttle..... small hard plastic wheel usually rides that cam and they do wear out.
Check that wheel and replace it if it is grooved and it should smooth out.
Since the OB is new to you I would also do the ignition and impellar too....
