Re: 1995 225 Mariner
You will need to get ahold of an adjustable gap spark tester and a DVA meter.
Test the spark on all cyl's, enlarge the gap and retest, you should be able to draw a nice blue arc up to a half inch on all cyl's.
If not, why not, that's where the DVA meter proves so handy to test the stator output to determine if you have a weak stator or to move on to testing other ignition components.