Stator question

[steplift20]

I had a problem this fall, I was out and my engine started acting up, hard to start and felt like it was only running on 3 cylinders, I think it could be the switch box or the stator, when I started it on land it ran good,no problems. I know that the stator can go in and out, if I check the stator with a multimeter and it was running good at the time will it show on the test that it is no Good? Or does it have to be running bad when I test it to show that it is bad. Any info would be great
Thank you
P.s. I am going to change the switch boxes this weekend.