I have a 1997 evinrude intruder v4 115hp. 2 days ago I was running at roughly 30 mph and the boat suddenly shut off and wouldn’t crank back up. 3 hours later when I got home it fired up and I immediately turned it off because I didn’t have it hooked up on muffs, didn’t think it would actually fire up. Went to use it today and it turned over and fired once then died. 20 minutes later it fired up and ran for 20 seconds. Any ideas on where to start figuring this issue out? New boat owner so not familiar with working on outboards/troubleshooting issues