My scenario: I was trying out a new prop yesterday trying to get my rpm's up to around 5600. According to my tach I hit the 5600 but as soon as I did the motor shut down and died. This happened to me twice. Not wanting to hurt the motor I went back to the ramp and changed back to my original prop which max's out at around 5400 rpm. I took the boat back out and tried once more and everything ran fine. On one of the occassions where the motor shut down at 5600 rpm my Lowrance also shut off as though I lost all my electric or at least dropped below the threshold voltage for my electronics to run.
My question: 1. Is there some reason as to what might have happened just by hitting 5600rpm? 2. It was very cold out on the lake yesterday and I can't swear to the absolute accuracy of the tach. What is a rev limiter and what does it do or how does it work? Someone at the ramp suggested that it might have been the problem. 3. There was some fouling on the spark plugs but seemed consistant for plugs 1-2-4-5-6. Plug 3 looked a little worse but still not that bad. When I got back home I pulled the plugs again and they were gapped at around .075 - .076. From what documentation I could find on this motor it said that is the correct gap? Once again this is an older Johnson Limited Edition. I think the actual year is 1990 or 91.
Any help here would greatly be appreciated. Thanks
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But you're right it should be .030
