[scottpellegrin]

Over the last few weeks my engine would misfire on occasion when at wide open throttle. Some times just a little blip, other times I would have to go to 3/4 throttle to get it to stop misfiring. Just last night I ran 3 miles across lake wissota with no trouble at all. I stopped and fished for about 45 min then started the engine again and was going to head up just a little farther. As soon as the boat got on plane the engine killed as if I had turned the key off, no spit or sputter at all. I checked for spark when I was on the water and there was none. Tonight when I got home from work I thought I would put the muffs on it and try to start it. Soon as I turned the key it fired and ran perfect. I let it run for about 5 minutes and then shut it off and wrote this message. Where do I begin with this thing, or what do you think the culprit might be? Just a note I worked on helicopters for 5 years so don’t be afraid to put me to work with troubleshooting this thing. Any help would be greatly appreciated.

[mikesea]

look for obvious wiring probs.but it sounds like your key switch may be going bad,OR if you have a safety lanyard,they do wear out and cause the kill circut to get the ground that kills the eng.If it happens while your out again,disconnect your red harness plug,jump your starter,if the problem goes away,its between the harness and switch usually,be CAREFUL,you will have no way to kill other than disconnecting fuel or manually choking,if you find no spark in the driveway,do the plug disconnect ,check spark,its probably something simple

[Walker]

I though I responded to this post yesterday. Anyway, I'd bet its your powerpack. I've seen several of those V6 Loopers act the same way. Eventually the powerpack will completely fail. Need to test it though. Expensive part to replace because you think its bad.